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OpenCloudOS-Kernel/lib/vsprintf.c

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treewide: Add SPDX license identifier for missed files Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-19 20:08:55 +08:00
// SPDX-License-Identifier: GPL-2.0-only
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/*
* linux/lib/vsprintf.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
/*
* Wirzenius wrote this portably, Torvalds fucked it up :-)
*/
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
/*
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
* - changed to provide snprintf and vsnprintf functions
* So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
* - scnprintf and vscnprintf
*/
#include <stdarg.h>
lib/vsprintf.c: move sizeof(struct printf_spec) next to its definition At the time of commit d048419311ff ("lib/vsprintf.c: expand field_width to 24 bits"), there was no compiletime_assert/BUILD_BUG/.... variant that could be used outside function scope. Now we have static_assert(), so move the assertion next to the definition instead of hiding it in some arbitrary function. Also add the appropriate #include to avoid relying on build_bug.h being pulled in via some arbitrary chain of includes. Link: http://lkml.kernel.org/r/20190208203015.29702-2-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-08 08:27:03 +08:00
#include <linux/build_bug.h>
lib/vsprintf.c: Include clk.h This file uses the clk API so it should include clk.h directly instead of indirectly including it through clk-provider.h. Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-20 06:00:46 +08:00
#include <linux/clk.h>
lib/vsprintf: add %pC{,n,r} format specifiers for clocks Add format specifiers for printing struct clk: - '%pC' or '%pCn': name (Common Clock Framework) or address (legacy clock framework) of the clock, - '%pCr': rate of the clock. [akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:20 +08:00
#include <linux/clk-provider.h>
printf: add support for printing symbolic error names It has been suggested several times to extend vsnprintf() to be able to convert the numeric value of ENOSPC to print "ENOSPC". This implements that as a %p extension: With %pe, one can do if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %pe\n", foo); return PTR_ERR(foo); } instead of what is seen in quite a few places in the kernel: if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %ld\n", PTR_ERR(foo)); return PTR_ERR(foo); } If the value passed to %pe is an ERR_PTR, but the library function errname() added here doesn't know about the value, the value is simply printed in decimal. If the value passed to %pe is not an ERR_PTR, we treat it as an ordinary %p and thus print the hashed value (passing non-ERR_PTR values to %pe indicates a bug in the caller, but we can't do much about that). With my embedded hat on, and because it's not very invasive to do, I've made it possible to remove this. The errname() function and associated lookup tables take up about 3K. For most, that's probably quite acceptable and a price worth paying for more readable dmesg (once this starts getting used), while for those that disable printk() it's of very little use - I don't see a procfs/sysfs/seq_printf() file reasonably making use of this - and they clearly want to squeeze vmlinux as much as possible. Hence the default y if PRINTK. The symbols to include have been found by massaging the output of find arch include -iname 'errno*.h' | xargs grep -E 'define\s*E' In the cases where some common aliasing exists (e.g. EAGAIN=EWOULDBLOCK on all platforms, EDEADLOCK=EDEADLK on most), I've moved the more popular one (in terms of 'git grep -w Efoo | wc) to the bottom so that one takes precedence. Link: http://lkml.kernel.org/r/20191015190706.15989-1-linux@rasmusvillemoes.dk To: "Jonathan Corbet" <corbet@lwn.net> To: linux-kernel@vger.kernel.org Cc: "Andy Shevchenko" <andy.shevchenko@gmail.com> Cc: "Andrew Morton" <akpm@linux-foundation.org> Cc: "Joe Perches" <joe@perches.com> Cc: linux-doc@vger.kernel.org Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Uwe Kleine-König <uwe@kleine-koenig.org> Reviewed-by: Petr Mladek <pmladek@suse.com> [andy.shevchenko@gmail.com: use abs()] Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-16 03:07:05 +08:00
#include <linux/errname.h>
lib: reduce the use of module.h wherever possible For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-11-17 10:29:17 +08:00
#include <linux/module.h> /* for KSYM_SYMBOL_LEN */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
#include <linux/kallsyms.h>
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
#include <linux/math64.h>
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
#include <linux/uaccess.h>
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
#include <linux/ioport.h>
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
#include <linux/dcache.h>
vsprintf: check real user/group id for %pK Some setuid binaries will allow reading of files which have read permission by the real user id. This is problematic with files which use %pK because the file access permission is checked at open() time, but the kptr_restrict setting is checked at read() time. If a setuid binary opens a %pK file as an unprivileged user, and then elevates permissions before reading the file, then kernel pointer values may be leaked. This happens for example with the setuid pppd application on Ubuntu 12.04: $ head -1 /proc/kallsyms 00000000 T startup_32 $ pppd file /proc/kallsyms pppd: In file /proc/kallsyms: unrecognized option 'c1000000' This will only leak the pointer value from the first line, but other setuid binaries may leak more information. Fix this by adding a check that in addition to the current process having CAP_SYSLOG, that effective user and group ids are equal to the real ids. If a setuid binary reads the contents of a file which uses %pK then the pointer values will be printed as NULL if the real user is unprivileged. Update the sysctl documentation to reflect the changes, and also correct the documentation to state the kptr_restrict=0 is the default. This is a only temporary solution to the issue. The correct solution is to do the permission check at open() time on files, and to replace %pK with a function which checks the open() time permission. %pK uses in printk should be removed since no sane permission check can be done, and instead protected by using dmesg_restrict. Signed-off-by: Ryan Mallon <rmallon@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Joe Perches <joe@perches.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 07:08:51 +08:00
#include <linux/cred.h>
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
#include <linux/rtc.h>
lib/uuid.c: introduce a few more generic helpers There are new helpers in this patch: uuid_is_valid checks if a UUID is valid uuid_be_to_bin converts from string to binary (big endian) uuid_le_to_bin converts from string to binary (little endian) They will be used in future, i.e. in the following patches in the series. This also moves the indices arrays to lib/uuid.c to be shared accross modules. [andriy.shevchenko@linux.intel.com: fix typo] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-21 08:01:04 +08:00
#include <linux/uuid.h>
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
#include <linux/of.h>
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
#include <net/addrconf.h>
printk: hash addresses printed with %p Currently there exist approximately 14 000 places in the kernel where addresses are being printed using an unadorned %p. This potentially leaks sensitive information regarding the Kernel layout in memory. Many of these calls are stale, instead of fixing every call lets hash the address by default before printing. This will of course break some users, forcing code printing needed addresses to be updated. Code that _really_ needs the address will soon be able to use the new printk specifier %px to print the address. For what it's worth, usage of unadorned %p can be broken down as follows (thanks to Joe Perches). $ git grep -E '%p[^A-Za-z0-9]' | cut -f1 -d"/" | sort | uniq -c 1084 arch 20 block 10 crypto 32 Documentation 8121 drivers 1221 fs 143 include 101 kernel 69 lib 100 mm 1510 net 40 samples 7 scripts 11 security 166 sound 152 tools 2 virt Add function ptr_to_id() to map an address to a 32 bit unique identifier. Hash any unadorned usage of specifier %p and any malformed specifiers. Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-01 12:32:23 +08:00
#include <linux/siphash.h>
#include <linux/compiler.h>
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
#include <linux/property.h>
lib/vsprintf: add %*pg format specifier This allow to directly print block_device name. Currently one should use bdevname() with temporal char buffer. This is very ineffective because bloat stack usage for deep IO call-traces Example: %pg -> sda, sda1 or loop0p1 [AV: fixed a minor braino - position updates should not be dependent upon having reached the of buffer] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-13 20:31:35 +08:00
#ifdef CONFIG_BLOCK
#include <linux/blkdev.h>
#endif
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
#include "../mm/internal.h" /* For the trace_print_flags arrays */
[PATCH] fix missing includes I recently picked up my older work to remove unnecessary #includes of sched.h, starting from a patch by Dave Jones to not include sched.h from module.h. This reduces the number of indirect includes of sched.h by ~300. Another ~400 pointless direct includes can be removed after this disentangling (patch to follow later). However, quite a few indirect includes need to be fixed up for this. In order to feed the patches through -mm with as little disturbance as possible, I've split out the fixes I accumulated up to now (complete for i386 and x86_64, more archs to follow later) and post them before the real patch. This way this large part of the patch is kept simple with only adding #includes, and all hunks are independent of each other. So if any hunk rejects or gets in the way of other patches, just drop it. My scripts will pick it up again in the next round. Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-31 07:03:48 +08:00
#include <asm/page.h> /* for PAGE_SIZE */
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
#include <asm/byteorder.h> /* cpu_to_le16 */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
lib/vsprintf: add %*pE[achnops] format specifier This allows user to print a given buffer as an escaped string. The rules are applied according to an optional mix of flags provided by additional format letters. For example, if the given buffer is: 1b 62 20 5c 43 07 22 90 0d 5d The result strings would be: %*pE "\eb \C\a"\220\r]" %*pEhp "\x1bb \C\x07"\x90\x0d]" %*pEa "\e\142\040\\\103\a\042\220\r\135" Please, read Documentation/printk-formats.txt and lib/string_helpers.c kernel documentation to get further information. [akpm@linux-foundation.org: tidy up comment layout, per Joe] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Joe Perches <joe@perches.com> Cc: "John W . Linville" <linville@tuxdriver.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 06:55:18 +08:00
#include <linux/string_helpers.h>
lib/kstrtox: common code between kstrto*() and simple_strto*() functions Currently termination logic (\0 or \n\0) is hardcoded in _kstrtoull(), avoid that for code reuse between kstrto*() and simple_strtoull(). Essentially, make them different only in termination logic. simple_strtoull() (and scanf(), BTW) ignores integer overflow, that's a bug we currently don't have guts to fix, making KSTRTOX_OVERFLOW hack necessary. Almost forgot: patch shrinks code size by about ~80 bytes on x86_64. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:28 +08:00
#include "kstrtox.h"
lib: pull base-guessing logic to helper function The default base is 10 unless there is a leading zero, in which case the base will be guessed as 8. The base will only be guesed as 16 when the string starts with '0x' the third character is a valid hex digit. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17 04:40:34 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/**
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
* simple_strtoull - convert a string to an unsigned long long
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
simple_strto*: annotate function as obsolete Update the documentation for simple_strto* to reflect that it has been obsoleted and advise the usage of kstrto*. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:03:05 +08:00
*
* This function is obsolete. Please use kstrtoull instead.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
lib/kstrtox: common code between kstrto*() and simple_strto*() functions Currently termination logic (\0 or \n\0) is hardcoded in _kstrtoull(), avoid that for code reuse between kstrto*() and simple_strtoull(). Essentially, make them different only in termination logic. simple_strtoull() (and scanf(), BTW) ignores integer overflow, that's a bug we currently don't have guts to fix, making KSTRTOX_OVERFLOW hack necessary. Almost forgot: patch shrinks code size by about ~80 bytes on x86_64. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:28 +08:00
unsigned long long result;
unsigned int rv;
lib: pull base-guessing logic to helper function The default base is 10 unless there is a leading zero, in which case the base will be guessed as 8. The base will only be guesed as 16 when the string starts with '0x' the third character is a valid hex digit. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17 04:40:34 +08:00
lib/kstrtox: common code between kstrto*() and simple_strto*() functions Currently termination logic (\0 or \n\0) is hardcoded in _kstrtoull(), avoid that for code reuse between kstrto*() and simple_strtoull(). Essentially, make them different only in termination logic. simple_strtoull() (and scanf(), BTW) ignores integer overflow, that's a bug we currently don't have guts to fix, making KSTRTOX_OVERFLOW hack necessary. Almost forgot: patch shrinks code size by about ~80 bytes on x86_64. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:28 +08:00
cp = _parse_integer_fixup_radix(cp, &base);
rv = _parse_integer(cp, base, &result);
/* FIXME */
cp += (rv & ~KSTRTOX_OVERFLOW);
lib: pull base-guessing logic to helper function The default base is 10 unless there is a leading zero, in which case the base will be guessed as 8. The base will only be guesed as 16 when the string starts with '0x' the third character is a valid hex digit. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17 04:40:34 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
if (endp)
*endp = (char *)cp;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return result;
}
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
EXPORT_SYMBOL(simple_strtoull);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/**
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
* simple_strtoul - convert a string to an unsigned long
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
simple_strto*: annotate function as obsolete Update the documentation for simple_strto* to reflect that it has been obsoleted and advise the usage of kstrto*. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:03:05 +08:00
*
* This function is obsolete. Please use kstrtoul instead.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
return simple_strtoull(cp, endp, base);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
EXPORT_SYMBOL(simple_strtoul);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/**
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
* simple_strtol - convert a string to a signed long
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
simple_strto*: annotate function as obsolete Update the documentation for simple_strto* to reflect that it has been obsoleted and advise the usage of kstrto*. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:03:05 +08:00
*
* This function is obsolete. Please use kstrtol instead.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
long simple_strtol(const char *cp, char **endp, unsigned int base)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
if (*cp == '-')
return -simple_strtoul(cp + 1, endp, base);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
return simple_strtoul(cp, endp, base);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
vsprintf: reuse almost identical simple_strtoulX() functions The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers: unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...} Both are same size on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it. As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull(). Code size decreases by 304 bytes: text data bss dec hex filename 15534 0 8 15542 3cb6 vsprintf.o (ex lib/lib.a-BEFORE) 15230 0 8 15238 3b86 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:01 +08:00
EXPORT_SYMBOL(simple_strtol);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/**
* simple_strtoll - convert a string to a signed long long
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
simple_strto*: annotate function as obsolete Update the documentation for simple_strto* to reflect that it has been obsoleted and advise the usage of kstrto*. Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:03:05 +08:00
*
* This function is obsolete. Please use kstrtoll instead.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
lib: trivial whitespace tidy Remove extra lines before the EXPORT_SYMBOL()s Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17 04:40:35 +08:00
long long simple_strtoll(const char *cp, char **endp, unsigned int base)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
if (*cp == '-')
lib: trivial whitespace tidy Remove extra lines before the EXPORT_SYMBOL()s Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17 04:40:35 +08:00
return -simple_strtoull(cp + 1, endp, base);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
lib: trivial whitespace tidy Remove extra lines before the EXPORT_SYMBOL()s Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-17 04:40:35 +08:00
return simple_strtoull(cp, endp, base);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
lib/vsprintf.c: add missing EXPORT_SYMBOL(simple_strtoll) Add a missing EXPORT_SYMBOL. I must be the first person that wants to use this function :-) Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-24 01:18:04 +08:00
EXPORT_SYMBOL(simple_strtoll);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
int skip_atoi(const char **s)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int i = 0;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
lib/vsprintf.c: replace while with do-while in skip_atoi All callers of skip_atoi have already checked for the first character being a digit. In this case, gcc generates simpler code for a do while-loop. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 07:01:42 +08:00
do {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
i = i*10 + *((*s)++) - '0';
lib/vsprintf.c: replace while with do-while in skip_atoi All callers of skip_atoi have already checked for the first character being a digit. In this case, gcc generates simpler code for a do while-loop. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 07:01:42 +08:00
} while (isdigit(**s));
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return i;
}
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/*
* Decimal conversion is by far the most typical, and is used for
* /proc and /sys data. This directly impacts e.g. top performance
* with many processes running. We optimize it for speed by emitting
* two characters at a time, using a 200 byte lookup table. This
* roughly halves the number of multiplications compared to computing
* the digits one at a time. Implementation strongly inspired by the
* previous version, which in turn used ideas described at
* <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
* from the author, Douglas W. Jones).
*
* It turns out there is precisely one 26 bit fixed-point
* approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
* holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
* range happens to be somewhat larger (x <= 1073741898), but that's
* irrelevant for our purpose.
*
* For dividing a number in the range [10^4, 10^6-1] by 100, we still
* need a 32x32->64 bit multiply, so we simply use the same constant.
*
* For dividing a number in the range [100, 10^4-1] by 100, there are
* several options. The simplest is (x * 0x147b) >> 19, which is valid
* for all x <= 43698.
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
*/
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
static const u16 decpair[100] = {
#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
_( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
_(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
_(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
_(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
_(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
_(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
_(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
_(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
_(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
_(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
#undef _
};
/*
* This will print a single '0' even if r == 0, since we would
lib/vsprintf.c: improve put_dec_trunc8 slightly I hadn't had enough coffee when I wrote this. Currently, the final increment of buf depends on the value loaded from the table, and causes gcc to emit a cmov immediately before the return. It is smarter to let it depend on r, since the increment can then be computed in parallel with the final load/store pair. It also shaves 16 bytes of .text. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:42 +08:00
* immediately jump to out_r where two 0s would be written but only
* one of them accounted for in buf. This is needed by ip4_string
* below. All other callers pass a non-zero value of r.
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
*/
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
char *put_dec_trunc8(char *buf, unsigned r)
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
{
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
unsigned q;
/* 1 <= r < 10^8 */
if (r < 100)
goto out_r;
/* 100 <= r < 10^8 */
q = (r * (u64)0x28f5c29) >> 32;
*((u16 *)buf) = decpair[r - 100*q];
buf += 2;
/* 1 <= q < 10^6 */
if (q < 100)
goto out_q;
/* 100 <= q < 10^6 */
r = (q * (u64)0x28f5c29) >> 32;
*((u16 *)buf) = decpair[q - 100*r];
buf += 2;
/* 1 <= r < 10^4 */
if (r < 100)
goto out_r;
/* 100 <= r < 10^4 */
q = (r * 0x147b) >> 19;
*((u16 *)buf) = decpair[r - 100*q];
buf += 2;
out_q:
/* 1 <= q < 100 */
r = q;
out_r:
/* 1 <= r < 100 */
*((u16 *)buf) = decpair[r];
lib/vsprintf.c: improve put_dec_trunc8 slightly I hadn't had enough coffee when I wrote this. Currently, the final increment of buf depends on the value loaded from the table, and causes gcc to emit a cmov immediately before the return. It is smarter to let it depend on r, since the increment can then be computed in parallel with the final load/store pair. It also shaves 16 bytes of .text. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:42 +08:00
buf += r < 10 ? 1 : 2;
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
return buf;
}
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
char *put_dec_full8(char *buf, unsigned r)
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
{
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
unsigned q;
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* 0 <= r < 10^8 */
q = (r * (u64)0x28f5c29) >> 32;
*((u16 *)buf) = decpair[r - 100*q];
buf += 2;
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* 0 <= q < 10^6 */
r = (q * (u64)0x28f5c29) >> 32;
*((u16 *)buf) = decpair[q - 100*r];
buf += 2;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* 0 <= r < 10^4 */
q = (r * 0x147b) >> 19;
*((u16 *)buf) = decpair[r - 100*q];
buf += 2;
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* 0 <= q < 100 */
*((u16 *)buf) = decpair[q];
buf += 2;
return buf;
}
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
static noinline_for_stack
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
char *put_dec(char *buf, unsigned long long n)
{
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
if (n >= 100*1000*1000)
buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
/* 1 <= n <= 1.6e11 */
if (n >= 100*1000*1000)
buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
/* 1 <= n < 1e8 */
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
return put_dec_trunc8(buf, n);
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
}
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
static void
put_dec_full4(char *buf, unsigned r)
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
{
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
unsigned q;
/* 0 <= r < 10^4 */
q = (r * 0x147b) >> 19;
*((u16 *)buf) = decpair[r - 100*q];
buf += 2;
/* 0 <= q < 100 */
*((u16 *)buf) = decpair[q];
lib: vsprintf: optimize division by 10000 The same multiply-by-inverse technique can be used to convert division by 10000 to a 32x32->64-bit multiply. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:12:29 +08:00
}
/*
* Call put_dec_full4 on x % 10000, return x / 10000.
* The approximation x/10000 == (x * 0x346DC5D7) >> 43
* holds for all x < 1,128,869,999. The largest value this
* helper will ever be asked to convert is 1,125,520,955.
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
* (second call in the put_dec code, assuming n is all-ones).
lib: vsprintf: optimize division by 10000 The same multiply-by-inverse technique can be used to convert division by 10000 to a 32x32->64-bit multiply. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:12:29 +08:00
*/
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
static noinline_for_stack
lib: vsprintf: optimize division by 10000 The same multiply-by-inverse technique can be used to convert division by 10000 to a 32x32->64-bit multiply. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:12:29 +08:00
unsigned put_dec_helper4(char *buf, unsigned x)
{
uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
put_dec_full4(buf, x - q * 10000);
return q;
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
}
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
/* Based on code by Douglas W. Jones found at
* <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
* (with permission from the author).
* Performs no 64-bit division and hence should be fast on 32-bit machines.
*/
static
char *put_dec(char *buf, unsigned long long n)
{
uint32_t d3, d2, d1, q, h;
if (n < 100*1000*1000)
return put_dec_trunc8(buf, n);
d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
h = (n >> 32);
d2 = (h ) & 0xffff;
d3 = (h >> 16); /* implicit "& 0xffff" */
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
= 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
lib: vsprintf: optimize division by 10000 The same multiply-by-inverse technique can be used to convert division by 10000 to a 32x32->64-bit multiply. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:12:29 +08:00
q = put_dec_helper4(buf, q);
q += 7671 * d3 + 9496 * d2 + 6 * d1;
q = put_dec_helper4(buf+4, q);
q += 4749 * d3 + 42 * d2;
q = put_dec_helper4(buf+8, q);
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
lib: vsprintf: optimize division by 10000 The same multiply-by-inverse technique can be used to convert division by 10000 to a 32x32->64-bit multiply. Signed-off-by: George Spelvin <linux@horizon.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:12:29 +08:00
q += 281 * d3;
buf += 12;
if (q)
buf = put_dec_trunc8(buf, q);
else while (buf[-1] == '0')
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
--buf;
return buf;
}
#endif
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
/*
* Convert passed number to decimal string.
* Returns the length of string. On buffer overflow, returns 0.
*
* If speed is not important, use snprintf(). It's easy to read the code.
*/
proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a specified minimal field width. It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it works much faster. == test_smaps.py num = 0 with open("/proc/1/smaps") as f: for x in xrange(10000): data = f.read() f.seek(0, 0) == == Before patch == $ time python test_smaps.py real 0m4.593s user 0m0.398s sys 0m4.158s == After patch == $ time python test_smaps.py real 0m3.828s user 0m0.413s sys 0m3.408s $ perf -g record python test_smaps.py == Before patch == - 79.01% 3.36% python [kernel.kallsyms] [k] show_smap.isra.33 - 75.65% show_smap.isra.33 + 48.85% seq_printf + 15.75% __walk_page_range + 9.70% show_map_vma.isra.23 0.61% seq_puts == After patch == - 75.51% 4.62% python [kernel.kallsyms] [k] show_smap.isra.33 - 70.88% show_smap.isra.33 + 24.82% seq_put_decimal_ull_w + 19.78% __walk_page_range + 12.74% seq_printf + 11.08% show_map_vma.isra.23 + 1.68% seq_puts [akpm@linux-foundation.org: fix drivers/of/unittest.c build] Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org Signed-off-by: Andrei Vagin <avagin@openvz.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 07:31:16 +08:00
int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
{
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* put_dec requires 2-byte alignment of the buffer. */
char tmp[sizeof(num) * 3] __aligned(2);
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
int idx, len;
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
/* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
if (num <= 9) {
tmp[0] = '0' + num;
len = 1;
} else {
len = put_dec(tmp, num) - tmp;
}
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a specified minimal field width. It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it works much faster. == test_smaps.py num = 0 with open("/proc/1/smaps") as f: for x in xrange(10000): data = f.read() f.seek(0, 0) == == Before patch == $ time python test_smaps.py real 0m4.593s user 0m0.398s sys 0m4.158s == After patch == $ time python test_smaps.py real 0m3.828s user 0m0.413s sys 0m3.408s $ perf -g record python test_smaps.py == Before patch == - 79.01% 3.36% python [kernel.kallsyms] [k] show_smap.isra.33 - 75.65% show_smap.isra.33 + 48.85% seq_printf + 15.75% __walk_page_range + 9.70% show_map_vma.isra.23 0.61% seq_puts == After patch == - 75.51% 4.62% python [kernel.kallsyms] [k] show_smap.isra.33 - 70.88% show_smap.isra.33 + 24.82% seq_put_decimal_ull_w + 19.78% __walk_page_range + 12.74% seq_printf + 11.08% show_map_vma.isra.23 + 1.68% seq_puts [akpm@linux-foundation.org: fix drivers/of/unittest.c build] Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org Signed-off-by: Andrei Vagin <avagin@openvz.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 07:31:16 +08:00
if (len > size || width > size)
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
return 0;
proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a specified minimal field width. It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it works much faster. == test_smaps.py num = 0 with open("/proc/1/smaps") as f: for x in xrange(10000): data = f.read() f.seek(0, 0) == == Before patch == $ time python test_smaps.py real 0m4.593s user 0m0.398s sys 0m4.158s == After patch == $ time python test_smaps.py real 0m3.828s user 0m0.413s sys 0m3.408s $ perf -g record python test_smaps.py == Before patch == - 79.01% 3.36% python [kernel.kallsyms] [k] show_smap.isra.33 - 75.65% show_smap.isra.33 + 48.85% seq_printf + 15.75% __walk_page_range + 9.70% show_map_vma.isra.23 0.61% seq_puts == After patch == - 75.51% 4.62% python [kernel.kallsyms] [k] show_smap.isra.33 - 70.88% show_smap.isra.33 + 24.82% seq_put_decimal_ull_w + 19.78% __walk_page_range + 12.74% seq_printf + 11.08% show_map_vma.isra.23 + 1.68% seq_puts [akpm@linux-foundation.org: fix drivers/of/unittest.c build] Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org Signed-off-by: Andrei Vagin <avagin@openvz.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 07:31:16 +08:00
if (width > len) {
width = width - len;
for (idx = 0; idx < width; idx++)
buf[idx] = ' ';
} else {
width = 0;
}
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
for (idx = 0; idx < len; ++idx)
proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a specified minimal field width. It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it works much faster. == test_smaps.py num = 0 with open("/proc/1/smaps") as f: for x in xrange(10000): data = f.read() f.seek(0, 0) == == Before patch == $ time python test_smaps.py real 0m4.593s user 0m0.398s sys 0m4.158s == After patch == $ time python test_smaps.py real 0m3.828s user 0m0.413s sys 0m3.408s $ perf -g record python test_smaps.py == Before patch == - 79.01% 3.36% python [kernel.kallsyms] [k] show_smap.isra.33 - 75.65% show_smap.isra.33 + 48.85% seq_printf + 15.75% __walk_page_range + 9.70% show_map_vma.isra.23 0.61% seq_puts == After patch == - 75.51% 4.62% python [kernel.kallsyms] [k] show_smap.isra.33 - 70.88% show_smap.isra.33 + 24.82% seq_put_decimal_ull_w + 19.78% __walk_page_range + 12.74% seq_printf + 11.08% show_map_vma.isra.23 + 1.68% seq_puts [akpm@linux-foundation.org: fix drivers/of/unittest.c build] Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org Signed-off-by: Andrei Vagin <avagin@openvz.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 07:31:16 +08:00
buf[idx + width] = tmp[len - idx - 1];
return len + width;
procfs: add num_to_str() to speed up /proc/stat == stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24 06:02:54 +08:00
}
lib/vsprintf.c: eliminate some branches Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few instructions by making SIGN have the value 1 instead of 2, and then use arithmetic instead of branches for computing the right spec->type. It's a little hacky, but certainly in the same spirit as SMALL needing to have the value 0x20. For example for the spec->qualifier == 'l' case, gcc now generates 75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx 762: 83 e2 01 and $0x1,%edx 765: 83 c2 09 add $0x9,%edx 768: 88 13 mov %dl,(%rbx) instead of 763: 0f b6 53 01 movzbl 0x1(%rbx),%edx 767: 83 e2 02 and $0x2,%edx 76a: 80 fa 01 cmp $0x1,%dl 76d: 19 d2 sbb %edx,%edx 76f: 83 c2 0a add $0xa,%edx 772: 88 13 mov %dl,(%rbx) Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:02 +08:00
#define SIGN 1 /* unsigned/signed, must be 1 */
lib/vsprintf.c: another small hack Making ZEROPAD == '0'-' ', we can eliminate a few more instructions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:11 +08:00
#define LEFT 2 /* left justified */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
#define PLUS 4 /* show plus */
#define SPACE 8 /* space if plus */
lib/vsprintf.c: another small hack Making ZEROPAD == '0'-' ', we can eliminate a few more instructions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:11 +08:00
#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
vsprintf: clarify comments for printf_spec flags Add clues about what the SMALL and SPECIAL flags do. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:31 +08:00
#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
enum format_type {
FORMAT_TYPE_NONE, /* Just a string part */
vsprintf: unify the format decoding layer for its 3 users, cleanup Impact: cleanup Rename FORMAT_TYPE_WITDH to => FORMAT_TYPE_WIDTH Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
FORMAT_TYPE_WIDTH,
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
FORMAT_TYPE_PRECISION,
FORMAT_TYPE_CHAR,
FORMAT_TYPE_STR,
FORMAT_TYPE_PTR,
FORMAT_TYPE_PERCENT_CHAR,
FORMAT_TYPE_INVALID,
FORMAT_TYPE_LONG_LONG,
FORMAT_TYPE_ULONG,
FORMAT_TYPE_LONG,
printk: add support of hh length modifier for printk Impact: new feature, extend vsprintf format strings hh is used as length modifier for signed char or unsigned char. It is supported by glibc, we add kernel support now. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: torvalds@linux-foundation.org Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49CC9739.30107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:07:05 +08:00
FORMAT_TYPE_UBYTE,
FORMAT_TYPE_BYTE,
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
FORMAT_TYPE_USHORT,
FORMAT_TYPE_SHORT,
FORMAT_TYPE_UINT,
FORMAT_TYPE_INT,
FORMAT_TYPE_SIZE_T,
FORMAT_TYPE_PTRDIFF
};
struct printf_spec {
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
unsigned int type:8; /* format_type enum */
signed int field_width:24; /* width of output field */
unsigned int flags:8; /* flags to number() */
unsigned int base:8; /* number base, 8, 10 or 16 only */
signed int precision:16; /* # of digits/chars */
} __packed;
lib/vsprintf.c: move sizeof(struct printf_spec) next to its definition At the time of commit d048419311ff ("lib/vsprintf.c: expand field_width to 24 bits"), there was no compiletime_assert/BUILD_BUG/.... variant that could be used outside function scope. Now we have static_assert(), so move the assertion next to the definition instead of hiding it in some arbitrary function. Also add the appropriate #include to avoid relying on build_bug.h being pulled in via some arbitrary chain of includes. Link: http://lkml.kernel.org/r/20190208203015.29702-2-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-08 08:27:03 +08:00
static_assert(sizeof(struct printf_spec) == 8);
lib/vsprintf.c: warn about too large precisions and field widths The field width is overloaded to pass some extra information for some %p extensions (e.g. #bits for %pb). But we might silently truncate the passed value when we stash it in struct printf_spec (see e.g. "lib/vsprintf.c: expand field_width to 24 bits"). Hopefully 23 value bits should now be enough for everybody, but if not, let's make some noise. Do the same for the precision. In both cases, clamping seems more sensible than truncating. While, according to POSIX, "A negative precision is taken as if the precision were omitted.", the kernel's printf has always treated that case as if the precision was 0, so we use that as lower bound. For the field width, the smallest representable value is actually -(1<<23), but a negative field width means 'set the LEFT flag and use the absolute value', so we want the absolute value to fit. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:44 +08:00
#define FIELD_WIDTH_MAX ((1 << 23) - 1)
#define PRECISION_MAX ((1 << 15) - 1)
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *number(char *buf, char *end, unsigned long long num,
struct printf_spec spec)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
/* put_dec requires 2-byte alignment of the buffer. */
char tmp[3 * sizeof(num)] __aligned(2);
x86: trivial printk optimizations In arch/x86/boot/printf.c gets rid of unused tail of digits: const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz"; (we are using 0-9a-f only) Uses smaller/faster lowercasing (by ORing with 0x20) if we know that we work on numbers/digits. Makes strtoul smaller, and also we are getting rid of static const char small_digits[] = "0123456789abcdefx"; static const char large_digits[] = "0123456789ABCDEFX"; since this works equally well: static const char digits[16] = "0123456789ABCDEF"; Size savings: $ size vmlinux.org vmlinux text data bss dec hex filename 877320 112252 90112 1079684 107984 vmlinux.org 877048 112252 90112 1079412 107874 vmlinux It may be also a tiny bit faster because code has less branches now, but I doubt it is measurable. [ hugh@veritas.com: uppercase pointers fix ] Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-10 06:24:09 +08:00
char sign;
char locase;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
int i;
lib/vsprintf.c: "%#o",0 becomes '0' instead of '00' number()'s behaviour is slighly changed: 0 becomes "0" instead of "00" when using the flag SPECIAL and base 8. Before: Number\Format %o %#o %x %#x 0 0 00 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 After: Number\Format %o %#o %x %#x 0 0 0 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 Signed-off-by: Pierre Carrier <pierre@spotify.com> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-30 06:07:35 +08:00
bool is_zero = num == 0LL;
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
int field_width = spec.field_width;
int precision = spec.precision;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
x86: trivial printk optimizations In arch/x86/boot/printf.c gets rid of unused tail of digits: const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz"; (we are using 0-9a-f only) Uses smaller/faster lowercasing (by ORing with 0x20) if we know that we work on numbers/digits. Makes strtoul smaller, and also we are getting rid of static const char small_digits[] = "0123456789abcdefx"; static const char large_digits[] = "0123456789ABCDEFX"; since this works equally well: static const char digits[16] = "0123456789ABCDEF"; Size savings: $ size vmlinux.org vmlinux text data bss dec hex filename 877320 112252 90112 1079684 107984 vmlinux.org 877048 112252 90112 1079412 107874 vmlinux It may be also a tiny bit faster because code has less branches now, but I doubt it is measurable. [ hugh@veritas.com: uppercase pointers fix ] Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-10 06:24:09 +08:00
/* locase = 0 or 0x20. ORing digits or letters with 'locase'
* produces same digits or (maybe lowercased) letters */
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
locase = (spec.flags & SMALL);
if (spec.flags & LEFT)
spec.flags &= ~ZEROPAD;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
sign = 0;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (spec.flags & SIGN) {
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
if ((signed long long)num < 0) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
sign = '-';
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
num = -(signed long long)num;
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
field_width--;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
} else if (spec.flags & PLUS) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
sign = '+';
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
field_width--;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
} else if (spec.flags & SPACE) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
sign = ' ';
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
field_width--;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
if (need_pfx) {
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (spec.base == 16)
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
field_width -= 2;
lib/vsprintf.c: "%#o",0 becomes '0' instead of '00' number()'s behaviour is slighly changed: 0 becomes "0" instead of "00" when using the flag SPECIAL and base 8. Before: Number\Format %o %#o %x %#x 0 0 00 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 After: Number\Format %o %#o %x %#x 0 0 0 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 Signed-off-by: Pierre Carrier <pierre@spotify.com> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-30 06:07:35 +08:00
else if (!is_zero)
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
field_width--;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* generate full string in tmp[], in reverse order */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
i = 0;
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
if (num < spec.base)
lib/vsprintf.c: eliminate duplicate hex string array gcc doesn't merge or overlap const char[] objects with identical contents (probably language lawyers would also insist that these things have different addresses), but there's no reason to have the string "0123456789ABCDEF" occur in multiple places. hex_asc_upper is declared in kernel.h and defined in lib/hexdump.c, which is unconditionally compiled in. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:08 +08:00
tmp[i++] = hex_asc_upper[num] | locase;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
else if (spec.base != 10) { /* 8 or 16 */
int mask = spec.base - 1;
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
int shift = 3;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
if (spec.base == 16)
shift = 4;
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
do {
lib/vsprintf.c: eliminate duplicate hex string array gcc doesn't merge or overlap const char[] objects with identical contents (probably language lawyers would also insist that these things have different addresses), but there's no reason to have the string "0123456789ABCDEF" occur in multiple places. hex_asc_upper is declared in kernel.h and defined in lib/hexdump.c, which is unconditionally compiled in. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:08 +08:00
tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
num >>= shift;
} while (num);
vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2 Optimize integer-to-string conversion in vsprintf.c for base 10. This is by far the most used conversion, and in some use cases it impacts performance. For example, top reads /proc/$PID/stat for every process, and with 4000 processes decimal conversion alone takes noticeable time. Using code from http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission from the author, Douglas W. Jones) binary-to-decimal-string conversion is done in groups of five digits at once, using only additions/subtractions/shifts (with -O2; -Os throws in some multiply instructions). On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code. This patch is run tested. Userspace benchmark/test is also attached. I tested it on PIII and AMD64 and new code is generally ~2.5 times faster. On AMD64: # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 12895992590592 ok... [Ctrl-C] # ./vsprintf_verify-O2 Original decimal conv: .......... 151 ns per iteration Patched decimal conv: .......... 62 ns per iteration Testing correctness 26025406464 ok... [Ctrl-C] More realistic test: top from busybox project was modified to report how many us it took to scan /proc (this does not account any processing done after that, like sorting process list), and then I test it with 4000 processes: #!/bin/sh i=4000 while test $i != 0; do sleep 30 & let i-- done busybox top -b -n3 >/dev/null on unpatched kernel: top: 4120 processes took 102864 microseconds to scan top: 4120 processes took 91757 microseconds to scan top: 4120 processes took 92517 microseconds to scan top: 4120 processes took 92581 microseconds to scan on patched kernel: top: 4120 processes took 75460 microseconds to scan top: 4120 processes took 66451 microseconds to scan top: 4120 processes took 67267 microseconds to scan top: 4120 processes took 67618 microseconds to scan The speedup comes from much faster generation of /proc/PID/stat by sprintf() calls inside the kernel. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:56 +08:00
} else { /* base 10 */
i = put_dec(tmp, num) - tmp;
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* printing 100 using %2d gives "100", not "00" */
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
if (i > precision)
precision = i;
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* leading space padding */
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
field_width -= precision;
lib/vsprintf.c: eliminate some branches Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few instructions by making SIGN have the value 1 instead of 2, and then use arithmetic instead of branches for computing the right spec->type. It's a little hacky, but certainly in the same spirit as SMALL needing to have the value 0x20. For example for the spec->qualifier == 'l' case, gcc now generates 75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx 762: 83 e2 01 and $0x1,%edx 765: 83 c2 09 add $0x9,%edx 768: 88 13 mov %dl,(%rbx) instead of 763: 0f b6 53 01 movzbl 0x1(%rbx),%edx 767: 83 e2 02 and $0x2,%edx 76a: 80 fa 01 cmp $0x1,%dl 76d: 19 d2 sbb %edx,%edx 76f: 83 c2 0a add $0xa,%edx 772: 88 13 mov %dl,(%rbx) Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:02 +08:00
if (!(spec.flags & (ZEROPAD | LEFT))) {
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
while (--field_width >= 0) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*buf = ' ';
++buf;
}
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* sign */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
if (sign) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*buf = sign;
++buf;
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* "0x" / "0" prefix */
if (need_pfx) {
lib/vsprintf.c: "%#o",0 becomes '0' instead of '00' number()'s behaviour is slighly changed: 0 becomes "0" instead of "00" when using the flag SPECIAL and base 8. Before: Number\Format %o %#o %x %#x 0 0 00 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 After: Number\Format %o %#o %x %#x 0 0 0 0 0x0 1 1 01 1 0x1 16 20 020 10 0x10 Signed-off-by: Pierre Carrier <pierre@spotify.com> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-30 06:07:35 +08:00
if (spec.base == 16 || !is_zero) {
if (buf < end)
*buf = '0';
++buf;
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (spec.base == 16) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
x86: trivial printk optimizations In arch/x86/boot/printf.c gets rid of unused tail of digits: const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz"; (we are using 0-9a-f only) Uses smaller/faster lowercasing (by ORing with 0x20) if we know that we work on numbers/digits. Makes strtoul smaller, and also we are getting rid of static const char small_digits[] = "0123456789abcdefx"; static const char large_digits[] = "0123456789ABCDEFX"; since this works equally well: static const char digits[16] = "0123456789ABCDEF"; Size savings: $ size vmlinux.org vmlinux text data bss dec hex filename 877320 112252 90112 1079684 107984 vmlinux.org 877048 112252 90112 1079412 107874 vmlinux It may be also a tiny bit faster because code has less branches now, but I doubt it is measurable. [ hugh@veritas.com: uppercase pointers fix ] Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-10 06:24:09 +08:00
*buf = ('X' | locase);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
++buf;
}
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* zero or space padding */
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (!(spec.flags & LEFT)) {
lib/vsprintf.c: another small hack Making ZEROPAD == '0'-' ', we can eliminate a few more instructions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:11 +08:00
char c = ' ' + (spec.flags & ZEROPAD);
BUILD_BUG_ON(' ' + ZEROPAD != '0');
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
while (--field_width >= 0) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*buf = c;
++buf;
}
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* hmm even more zero padding? */
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
while (i <= --precision) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*buf = '0';
++buf;
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* actual digits of result */
while (--i >= 0) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*buf = tmp[i];
++buf;
}
vsprintf.c: optimizing, part 1 (easy and obvious stuff) * There is no point in having full "0...9a...z" constant vector, if we use only "0...9a...f" (and "x" for "0x"). * Post-decrement usually needs a few more instructions, so use pre decrement instead where makes sense: -       while (i < precision--) { +       while (i <= --precision) { * if base != 10 (=> base 8 or 16), we can avoid using division in a loop and use mask/shift, obtaining much faster conversion. (More complex optimization for base 10 case is in the second patch). Overall, size vsprintf.o shows ~80 bytes smaller text section with this patch applied. Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:41:54 +08:00
/* trailing space padding */
lib/vsprintf.c: help gcc make number() smaller One consequence of the reorganization of struct printf_spec to make field_width 24 bits was that number() gained about 180 bytes. Since spec is never passed to other functions, we can help gcc make number() lose most of that extra weight by using local variables for the field width and precision. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:41 +08:00
while (--field_width >= 0) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (buf < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*buf = ' ';
++buf;
}
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return buf;
}
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
static noinline_for_stack
char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
{
struct printf_spec spec;
spec.type = FORMAT_TYPE_PTR;
spec.field_width = 2 + 2 * size; /* 0x + hex */
spec.flags = SPECIAL | SMALL | ZEROPAD;
spec.base = 16;
spec.precision = -1;
return number(buf, end, num, spec);
}
lib/vsprintf.c: pull out padding code from dentry_name() Pull out the logic in dentry_name() which handles field width space padding, in preparation for reusing it from string(). Rename the widen() helper to move_right(), since it is used for handling the !(flags & LEFT) case. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:28 +08:00
static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
{
size_t size;
if (buf >= end) /* nowhere to put anything */
return;
size = end - buf;
if (size <= spaces) {
memset(buf, ' ', size);
return;
}
if (len) {
if (len > size - spaces)
len = size - spaces;
memmove(buf + spaces, buf, len);
}
memset(buf, ' ', spaces);
}
lib/vsprintf.c: pull out padding code from dentry_name() Pull out the logic in dentry_name() which handles field width space padding, in preparation for reusing it from string(). Rename the widen() helper to move_right(), since it is used for handling the !(flags & LEFT) case. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:28 +08:00
/*
* Handle field width padding for a string.
* @buf: current buffer position
* @n: length of string
* @end: end of output buffer
* @spec: for field width and flags
* Returns: new buffer position after padding.
*/
static noinline_for_stack
char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
{
unsigned spaces;
if (likely(n >= spec.field_width))
return buf;
/* we want to pad the sucker */
spaces = spec.field_width - n;
if (!(spec.flags & LEFT)) {
move_right(buf - n, end, n, spaces);
return buf + spaces;
}
while (spaces--) {
if (buf < end)
*buf = ' ';
++buf;
}
return buf;
}
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
/* Handle string from a well known address. */
static char *string_nocheck(char *buf, char *end, const char *s,
struct printf_spec spec)
lib/vsprintf.c: move string() below widen_string() This is pure code movement, making sure the widen_string() helper is defined before the string() function. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:31 +08:00
{
lib/vsprintf.c: eliminate potential race in string() If the string corresponding to a %s specifier can change under us, we might end up copying a \0 byte to the output buffer. There might be callers who expect the output buffer to contain a genuine C string whose length is exactly the snprintf return value (assuming truncation hasn't happened or has been checked for). We can avoid this by only passing over the source string once, stopping the first time we meet a nul byte (or when we reach the given precision), and then letting widen_string() handle left/right space padding. As a small bonus, this code reuse also makes the generated code slightly smaller. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:34 +08:00
int len = 0;
vsprintf: fix data type of variable in string_nocheck() This patch fixes data type of precision with int. The precision is declared as signed int in struct printf_spec. Link: http://lkml.kernel.org/r/040301d51f60$b4959100$1dc0b300$@samsung.com To: <andriy.shevchenko@linux.intel.com> To: <geert+renesas@glider.be> To: <rostedt@goodmis.org> To: <me@tobin.cc> Signed-off-by: Youngmin Nam <youngmin.nam@samsung.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-06-10 15:47:07 +08:00
int lim = spec.precision;
lib/vsprintf.c: move string() below widen_string() This is pure code movement, making sure the widen_string() helper is defined before the string() function. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:31 +08:00
lib/vsprintf.c: eliminate potential race in string() If the string corresponding to a %s specifier can change under us, we might end up copying a \0 byte to the output buffer. There might be callers who expect the output buffer to contain a genuine C string whose length is exactly the snprintf return value (assuming truncation hasn't happened or has been checked for). We can avoid this by only passing over the source string once, stopping the first time we meet a nul byte (or when we reach the given precision), and then letting widen_string() handle left/right space padding. As a small bonus, this code reuse also makes the generated code slightly smaller. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:34 +08:00
while (lim--) {
char c = *s++;
if (!c)
break;
lib/vsprintf.c: move string() below widen_string() This is pure code movement, making sure the widen_string() helper is defined before the string() function. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:31 +08:00
if (buf < end)
lib/vsprintf.c: eliminate potential race in string() If the string corresponding to a %s specifier can change under us, we might end up copying a \0 byte to the output buffer. There might be callers who expect the output buffer to contain a genuine C string whose length is exactly the snprintf return value (assuming truncation hasn't happened or has been checked for). We can avoid this by only passing over the source string once, stopping the first time we meet a nul byte (or when we reach the given precision), and then letting widen_string() handle left/right space padding. As a small bonus, this code reuse also makes the generated code slightly smaller. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:34 +08:00
*buf = c;
lib/vsprintf.c: move string() below widen_string() This is pure code movement, making sure the widen_string() helper is defined before the string() function. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:31 +08:00
++buf;
lib/vsprintf.c: eliminate potential race in string() If the string corresponding to a %s specifier can change under us, we might end up copying a \0 byte to the output buffer. There might be callers who expect the output buffer to contain a genuine C string whose length is exactly the snprintf return value (assuming truncation hasn't happened or has been checked for). We can avoid this by only passing over the source string once, stopping the first time we meet a nul byte (or when we reach the given precision), and then letting widen_string() handle left/right space padding. As a small bonus, this code reuse also makes the generated code slightly smaller. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:34 +08:00
++len;
lib/vsprintf.c: move string() below widen_string() This is pure code movement, making sure the widen_string() helper is defined before the string() function. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:31 +08:00
}
lib/vsprintf.c: eliminate potential race in string() If the string corresponding to a %s specifier can change under us, we might end up copying a \0 byte to the output buffer. There might be callers who expect the output buffer to contain a genuine C string whose length is exactly the snprintf return value (assuming truncation hasn't happened or has been checked for). We can avoid this by only passing over the source string once, stopping the first time we meet a nul byte (or when we reach the given precision), and then letting widen_string() handle left/right space padding. As a small bonus, this code reuse also makes the generated code slightly smaller. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:34 +08:00
return widen_string(buf, len, end, spec);
lib/vsprintf.c: move string() below widen_string() This is pure code movement, making sure the widen_string() helper is defined before the string() function. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:31 +08:00
}
printf: add support for printing symbolic error names It has been suggested several times to extend vsnprintf() to be able to convert the numeric value of ENOSPC to print "ENOSPC". This implements that as a %p extension: With %pe, one can do if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %pe\n", foo); return PTR_ERR(foo); } instead of what is seen in quite a few places in the kernel: if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %ld\n", PTR_ERR(foo)); return PTR_ERR(foo); } If the value passed to %pe is an ERR_PTR, but the library function errname() added here doesn't know about the value, the value is simply printed in decimal. If the value passed to %pe is not an ERR_PTR, we treat it as an ordinary %p and thus print the hashed value (passing non-ERR_PTR values to %pe indicates a bug in the caller, but we can't do much about that). With my embedded hat on, and because it's not very invasive to do, I've made it possible to remove this. The errname() function and associated lookup tables take up about 3K. For most, that's probably quite acceptable and a price worth paying for more readable dmesg (once this starts getting used), while for those that disable printk() it's of very little use - I don't see a procfs/sysfs/seq_printf() file reasonably making use of this - and they clearly want to squeeze vmlinux as much as possible. Hence the default y if PRINTK. The symbols to include have been found by massaging the output of find arch include -iname 'errno*.h' | xargs grep -E 'define\s*E' In the cases where some common aliasing exists (e.g. EAGAIN=EWOULDBLOCK on all platforms, EDEADLOCK=EDEADLK on most), I've moved the more popular one (in terms of 'git grep -w Efoo | wc) to the bottom so that one takes precedence. Link: http://lkml.kernel.org/r/20191015190706.15989-1-linux@rasmusvillemoes.dk To: "Jonathan Corbet" <corbet@lwn.net> To: linux-kernel@vger.kernel.org Cc: "Andy Shevchenko" <andy.shevchenko@gmail.com> Cc: "Andrew Morton" <akpm@linux-foundation.org> Cc: "Joe Perches" <joe@perches.com> Cc: linux-doc@vger.kernel.org Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Uwe Kleine-König <uwe@kleine-koenig.org> Reviewed-by: Petr Mladek <pmladek@suse.com> [andy.shevchenko@gmail.com: use abs()] Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-16 03:07:05 +08:00
static char *err_ptr(char *buf, char *end, void *ptr,
struct printf_spec spec)
{
int err = PTR_ERR(ptr);
const char *sym = errname(err);
if (sym)
return string_nocheck(buf, end, sym, spec);
/*
* Somebody passed ERR_PTR(-1234) or some other non-existing
* Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to
* printing it as its decimal representation.
*/
spec.flags |= SIGN;
spec.base = 10;
return number(buf, end, err, spec);
}
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
/* Be careful: error messages must fit into the given buffer. */
static char *error_string(char *buf, char *end, const char *s,
struct printf_spec spec)
{
/*
* Hard limit to avoid a completely insane messages. It actually
* works pretty well because most error messages are in
* the many pointer format modifiers.
*/
if (spec.precision == -1)
spec.precision = 2 * sizeof(void *);
return string_nocheck(buf, end, s, spec);
}
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
/*
vsprintf: Do not break early boot with probing addresses The commit 3e5903eb9cff70730 ("vsprintf: Prevent crash when dereferencing invalid pointers") broke boot on several architectures. The common pattern is that probe_kernel_read() is not working during early boot because userspace access framework is not ready. It is a generic problem. We have to avoid any complex external functions in vsprintf() code, especially in the common path. They might break printk() easily and are hard to debug. Replace probe_kernel_read() with some simple checks for obvious problems. Details: 1. Report on Power: Kernel crashes very early during boot with with CONFIG_PPC_KUAP and CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG The problem is the combination of some new code called via printk(), check_pointer() which calls probe_kernel_read(). That then calls allow_user_access() (PPC_KUAP) and that uses mmu_has_feature() too early (before we've patched features). With the JUMP_LABEL debug enabled that causes us to call printk() & dump_stack() and we end up recursing and overflowing the stack. Because it happens so early you don't get any output, just an apparently dead system. The stack trace (which you don't see) is something like: ... dump_stack+0xdc probe_kernel_read+0x1a4 check_pointer+0x58 string+0x3c vsnprintf+0x1bc vscnprintf+0x20 printk_safe_log_store+0x7c printk+0x40 dump_stack_print_info+0xbc dump_stack+0x8 probe_kernel_read+0x1a4 probe_kernel_read+0x19c check_pointer+0x58 string+0x3c vsnprintf+0x1bc vscnprintf+0x20 vprintk_store+0x6c vprintk_emit+0xec vprintk_func+0xd4 printk+0x40 cpufeatures_process_feature+0xc8 scan_cpufeatures_subnodes+0x380 of_scan_flat_dt_subnodes+0xb4 dt_cpu_ftrs_scan_callback+0x158 of_scan_flat_dt+0xf0 dt_cpu_ftrs_scan+0x3c early_init_devtree+0x360 early_setup+0x9c 2. Report on s390: vsnprintf invocations, are broken on s390. For example, the early boot output now looks like this where the first (efault) should be the linux_banner: [ 0.099985] (efault) [ 0.099985] setup: Linux is running as a z/VM guest operating system in 64-bit mode [ 0.100066] setup: The maximum memory size is 8192MB [ 0.100070] cma: Reserved 4 MiB at (efault) [ 0.100100] numa: NUMA mode: (efault) The reason for this, is that the code assumes that probe_kernel_address() works very early. This however is not true on at least s390. Uaccess on KERNEL_DS works only after page tables have been setup on s390, which happens with setup_arch()->paging_init(). Any probe_kernel_address() invocation before that will return -EFAULT. Fixes: 3e5903eb9cff70730 ("vsprintf: Prevent crash when dereferencing invalid pointers") Link: http://lkml.kernel.org/r/20190510084213.22149-1-pmladek@suse.com Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Michal Hocko <mhocko@suse.cz> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-kernel@vger.kernel.org Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Cc: Russell Currey <ruscur@russell.cc> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Stephen Rothwell <sfr@ozlabs.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-arch@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-05-10 16:42:13 +08:00
* Do not call any complex external code here. Nested printk()/vsprintf()
* might cause infinite loops. Failures might break printk() and would
* be hard to debug.
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
*/
static const char *check_pointer_msg(const void *ptr)
{
if (!ptr)
return "(null)";
vsprintf: Do not break early boot with probing addresses The commit 3e5903eb9cff70730 ("vsprintf: Prevent crash when dereferencing invalid pointers") broke boot on several architectures. The common pattern is that probe_kernel_read() is not working during early boot because userspace access framework is not ready. It is a generic problem. We have to avoid any complex external functions in vsprintf() code, especially in the common path. They might break printk() easily and are hard to debug. Replace probe_kernel_read() with some simple checks for obvious problems. Details: 1. Report on Power: Kernel crashes very early during boot with with CONFIG_PPC_KUAP and CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG The problem is the combination of some new code called via printk(), check_pointer() which calls probe_kernel_read(). That then calls allow_user_access() (PPC_KUAP) and that uses mmu_has_feature() too early (before we've patched features). With the JUMP_LABEL debug enabled that causes us to call printk() & dump_stack() and we end up recursing and overflowing the stack. Because it happens so early you don't get any output, just an apparently dead system. The stack trace (which you don't see) is something like: ... dump_stack+0xdc probe_kernel_read+0x1a4 check_pointer+0x58 string+0x3c vsnprintf+0x1bc vscnprintf+0x20 printk_safe_log_store+0x7c printk+0x40 dump_stack_print_info+0xbc dump_stack+0x8 probe_kernel_read+0x1a4 probe_kernel_read+0x19c check_pointer+0x58 string+0x3c vsnprintf+0x1bc vscnprintf+0x20 vprintk_store+0x6c vprintk_emit+0xec vprintk_func+0xd4 printk+0x40 cpufeatures_process_feature+0xc8 scan_cpufeatures_subnodes+0x380 of_scan_flat_dt_subnodes+0xb4 dt_cpu_ftrs_scan_callback+0x158 of_scan_flat_dt+0xf0 dt_cpu_ftrs_scan+0x3c early_init_devtree+0x360 early_setup+0x9c 2. Report on s390: vsnprintf invocations, are broken on s390. For example, the early boot output now looks like this where the first (efault) should be the linux_banner: [ 0.099985] (efault) [ 0.099985] setup: Linux is running as a z/VM guest operating system in 64-bit mode [ 0.100066] setup: The maximum memory size is 8192MB [ 0.100070] cma: Reserved 4 MiB at (efault) [ 0.100100] numa: NUMA mode: (efault) The reason for this, is that the code assumes that probe_kernel_address() works very early. This however is not true on at least s390. Uaccess on KERNEL_DS works only after page tables have been setup on s390, which happens with setup_arch()->paging_init(). Any probe_kernel_address() invocation before that will return -EFAULT. Fixes: 3e5903eb9cff70730 ("vsprintf: Prevent crash when dereferencing invalid pointers") Link: http://lkml.kernel.org/r/20190510084213.22149-1-pmladek@suse.com Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Michal Hocko <mhocko@suse.cz> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-kernel@vger.kernel.org Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Cc: Russell Currey <ruscur@russell.cc> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Stephen Rothwell <sfr@ozlabs.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-arch@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-05-10 16:42:13 +08:00
if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
return "(efault)";
return NULL;
}
static int check_pointer(char **buf, char *end, const void *ptr,
struct printf_spec spec)
{
const char *err_msg;
err_msg = check_pointer_msg(ptr);
if (err_msg) {
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
*buf = error_string(*buf, end, err_msg, spec);
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
return -EFAULT;
}
return 0;
}
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
static noinline_for_stack
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
char *string(char *buf, char *end, const char *s,
struct printf_spec spec)
{
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, s, spec))
return buf;
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, s, spec);
}
lib/vsprintf: Make function pointer_string static Fix sparse warning: lib/vsprintf.c:673:6: warning: symbol 'pointer_string' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20190426164630.22104-1-yuehaibing@huawei.com To: <sergey.senozhatsky@gmail.com> To: <andriy.shevchenko@linux.intel.com> To: <geert+renesas@glider.be> To: <rostedt@goodmis.org> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-27 00:46:30 +08:00
static char *pointer_string(char *buf, char *end,
const void *ptr,
struct printf_spec spec)
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
{
spec.base = 16;
spec.flags |= SMALL;
if (spec.field_width == -1) {
spec.field_width = 2 * sizeof(ptr);
spec.flags |= ZEROPAD;
}
return number(buf, end, (unsigned long int)ptr, spec);
}
/* Make pointers available for printing early in the boot sequence. */
static int debug_boot_weak_hash __ro_after_init;
static int __init debug_boot_weak_hash_enable(char *str)
{
debug_boot_weak_hash = 1;
pr_info("debug_boot_weak_hash enabled\n");
return 0;
}
early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
static siphash_key_t ptr_key __read_mostly;
static void enable_ptr_key_workfn(struct work_struct *work)
{
get_random_bytes(&ptr_key, sizeof(ptr_key));
/* Needs to run from preemptible context */
static_branch_disable(&not_filled_random_ptr_key);
}
static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
static void fill_random_ptr_key(struct random_ready_callback *unused)
{
/* This may be in an interrupt handler. */
queue_work(system_unbound_wq, &enable_ptr_key_work);
}
static struct random_ready_callback random_ready = {
.func = fill_random_ptr_key
};
static int __init initialize_ptr_random(void)
{
int key_size = sizeof(ptr_key);
int ret;
/* Use hw RNG if available. */
if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
static_branch_disable(&not_filled_random_ptr_key);
return 0;
}
ret = add_random_ready_callback(&random_ready);
if (!ret) {
return 0;
} else if (ret == -EALREADY) {
/* This is in preemptible context */
enable_ptr_key_workfn(&enable_ptr_key_work);
return 0;
}
return ret;
}
early_initcall(initialize_ptr_random);
/* Maps a pointer to a 32 bit unique identifier. */
rss_stat: add support to detect RSS updates of external mm When a process updates the RSS of a different process, the rss_stat tracepoint appears in the context of the process doing the update. This can confuse userspace that the RSS of process doing the update is updated, while in reality a different process's RSS was updated. This issue happens in reclaim paths such as with direct reclaim or background reclaim. This patch adds more information to the tracepoint about whether the mm being updated belongs to the current process's context (curr field). We also include a hash of the mm pointer so that the process who the mm belongs to can be uniquely identified (mm_id field). Also vsprintf.c is refactored a bit to allow reuse of hashing code. [akpm@linux-foundation.org: remove unused local `str'] [joelaf@google.com: inline call to ptr_to_hashval] Link: http://lore.kernel.org/r/20191113153816.14b95acd@gandalf.local.home Link: http://lkml.kernel.org/r/20191114164622.GC233237@google.com Link: http://lkml.kernel.org/r/20191106024452.81923-1-joel@joelfernandes.org Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reported-by: Ioannis Ilkos <ilkos@google.com> Acked-by: Petr Mladek <pmladek@suse.com> [lib/vsprintf.c] Cc: Tim Murray <timmurray@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Carmen Jackson <carmenjackson@google.com> Cc: Mayank Gupta <mayankgupta@google.com> Cc: Daniel Colascione <dancol@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Minchan Kim <minchan@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01 09:50:33 +08:00
static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
{
unsigned long hashval;
if (static_branch_unlikely(&not_filled_random_ptr_key))
return -EAGAIN;
#ifdef CONFIG_64BIT
hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
/*
* Mask off the first 32 bits, this makes explicit that we have
* modified the address (and 32 bits is plenty for a unique ID).
*/
hashval = hashval & 0xffffffff;
#else
hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
#endif
*hashval_out = hashval;
return 0;
}
int ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
{
return __ptr_to_hashval(ptr, hashval_out);
}
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
static char *ptr_to_id(char *buf, char *end, const void *ptr,
struct printf_spec spec)
{
const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
unsigned long hashval;
rss_stat: add support to detect RSS updates of external mm When a process updates the RSS of a different process, the rss_stat tracepoint appears in the context of the process doing the update. This can confuse userspace that the RSS of process doing the update is updated, while in reality a different process's RSS was updated. This issue happens in reclaim paths such as with direct reclaim or background reclaim. This patch adds more information to the tracepoint about whether the mm being updated belongs to the current process's context (curr field). We also include a hash of the mm pointer so that the process who the mm belongs to can be uniquely identified (mm_id field). Also vsprintf.c is refactored a bit to allow reuse of hashing code. [akpm@linux-foundation.org: remove unused local `str'] [joelaf@google.com: inline call to ptr_to_hashval] Link: http://lore.kernel.org/r/20191113153816.14b95acd@gandalf.local.home Link: http://lkml.kernel.org/r/20191114164622.GC233237@google.com Link: http://lkml.kernel.org/r/20191106024452.81923-1-joel@joelfernandes.org Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reported-by: Ioannis Ilkos <ilkos@google.com> Acked-by: Petr Mladek <pmladek@suse.com> [lib/vsprintf.c] Cc: Tim Murray <timmurray@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Carmen Jackson <carmenjackson@google.com> Cc: Mayank Gupta <mayankgupta@google.com> Cc: Daniel Colascione <dancol@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Minchan Kim <minchan@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01 09:50:33 +08:00
int ret;
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
vsprintf: don't obfuscate NULL and error pointers I don't see what security concern is addressed by obfuscating NULL and IS_ERR() error pointers, printed with %p/%pK. Given the number of sites where %p is used (over 10000) and the fact that NULL pointers aren't uncommon, it probably wouldn't take long for an attacker to find the hash that corresponds to 0. Although harder, the same goes for most common error values, such as -1, -2, -11, -14, etc. The NULL part actually fixes a regression: NULL pointers weren't obfuscated until commit 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") which went into 5.2. I'm tacking the IS_ERR() part on here because error pointers won't leak kernel addresses and printing them as pointers shouldn't be any different from e.g. %d with PTR_ERR_OR_ZERO(). Obfuscating them just makes debugging based on existing pr_debug and friends excruciating. Note that the "always print 0's for %pK when kptr_restrict == 2" behaviour which goes way back is left as is. Example output with the patch applied: ptr error-ptr NULL %p: 0000000001f8cc5b fffffffffffffff2 0000000000000000 %pK, kptr = 0: 0000000001f8cc5b fffffffffffffff2 0000000000000000 %px: ffff888048c04020 fffffffffffffff2 0000000000000000 %pK, kptr = 1: ffff888048c04020 fffffffffffffff2 0000000000000000 %pK, kptr = 2: 0000000000000000 0000000000000000 0000000000000000 Fixes: 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-19 19:26:57 +08:00
/*
* Print the real pointer value for NULL and error pointers,
* as they are not actual addresses.
*/
if (IS_ERR_OR_NULL(ptr))
return pointer_string(buf, end, ptr, spec);
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
/* When debugging early boot use non-cryptographically secure hash. */
if (unlikely(debug_boot_weak_hash)) {
hashval = hash_long((unsigned long)ptr, 32);
return pointer_string(buf, end, (const void *)hashval, spec);
}
rss_stat: add support to detect RSS updates of external mm When a process updates the RSS of a different process, the rss_stat tracepoint appears in the context of the process doing the update. This can confuse userspace that the RSS of process doing the update is updated, while in reality a different process's RSS was updated. This issue happens in reclaim paths such as with direct reclaim or background reclaim. This patch adds more information to the tracepoint about whether the mm being updated belongs to the current process's context (curr field). We also include a hash of the mm pointer so that the process who the mm belongs to can be uniquely identified (mm_id field). Also vsprintf.c is refactored a bit to allow reuse of hashing code. [akpm@linux-foundation.org: remove unused local `str'] [joelaf@google.com: inline call to ptr_to_hashval] Link: http://lore.kernel.org/r/20191113153816.14b95acd@gandalf.local.home Link: http://lkml.kernel.org/r/20191114164622.GC233237@google.com Link: http://lkml.kernel.org/r/20191106024452.81923-1-joel@joelfernandes.org Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reported-by: Ioannis Ilkos <ilkos@google.com> Acked-by: Petr Mladek <pmladek@suse.com> [lib/vsprintf.c] Cc: Tim Murray <timmurray@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Carmen Jackson <carmenjackson@google.com> Cc: Mayank Gupta <mayankgupta@google.com> Cc: Daniel Colascione <dancol@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Minchan Kim <minchan@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01 09:50:33 +08:00
ret = __ptr_to_hashval(ptr, &hashval);
if (ret) {
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
spec.field_width = 2 * sizeof(ptr);
/* string length must be less than default_width */
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, str, spec);
lib/vsprintf: Prepare for more general use of ptr_to_id() Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:47 +08:00
}
return pointer_string(buf, end, (const void *)hashval, spec);
}
vsprintf: Shuffle restricted_pointer() This is just a preparation step for further changes. The patch does not change the code. Link: http://lkml.kernel.org/r/20190417115350.20479-2-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:41 +08:00
int kptr_restrict __read_mostly;
static noinline_for_stack
char *restricted_pointer(char *buf, char *end, const void *ptr,
struct printf_spec spec)
{
switch (kptr_restrict) {
case 0:
vsprintf: Consistent %pK handling for kptr_restrict == 0 restricted_pointer() pretends that it prints the address when kptr_restrict is set to zero. But it is never called in this situation. Instead, pointer() falls back to ptr_to_id() and hashes the pointer. This patch removes the potential confusion. klp_restrict is checked only in restricted_pointer(). It actually fixes a small race when the address might get printed unhashed: CPU0 CPU1 pointer() if (!kptr_restrict) /* for example set to 2 */ restricted_pointer() /* echo 0 >/proc/sys/kernel/kptr_restrict */ proc_dointvec_minmax_sysadmin() klpr_restrict = 0; switch(kptr_restrict) case 0: break: number() Fixes: ef0010a30935de4e0211 ("vsprintf: don't use 'restricted_pointer()' when not restricting") Link: http://lkml.kernel.org/r/20190417115350.20479-3-pmladek@suse.com To: Andy Shevchenko <andriy.shevchenko@linux.intel.com> To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:42 +08:00
/* Handle as %p, hash and do _not_ leak addresses. */
return ptr_to_id(buf, end, ptr, spec);
vsprintf: Shuffle restricted_pointer() This is just a preparation step for further changes. The patch does not change the code. Link: http://lkml.kernel.org/r/20190417115350.20479-2-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:41 +08:00
case 1: {
const struct cred *cred;
/*
* kptr_restrict==1 cannot be used in IRQ context
* because its test for CAP_SYSLOG would be meaningless.
*/
if (in_irq() || in_serving_softirq() || in_nmi()) {
if (spec.field_width == -1)
spec.field_width = 2 * sizeof(ptr);
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "pK-error", spec);
vsprintf: Shuffle restricted_pointer() This is just a preparation step for further changes. The patch does not change the code. Link: http://lkml.kernel.org/r/20190417115350.20479-2-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:41 +08:00
}
/*
* Only print the real pointer value if the current
* process has CAP_SYSLOG and is running with the
* same credentials it started with. This is because
* access to files is checked at open() time, but %pK
* checks permission at read() time. We don't want to
* leak pointer values if a binary opens a file using
* %pK and then elevates privileges before reading it.
*/
cred = current_cred();
if (!has_capability_noaudit(current, CAP_SYSLOG) ||
!uid_eq(cred->euid, cred->uid) ||
!gid_eq(cred->egid, cred->gid))
ptr = NULL;
break;
}
case 2:
default:
/* Always print 0's for %pK */
ptr = NULL;
break;
}
return pointer_string(buf, end, ptr, spec);
}
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
static noinline_for_stack
char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
const char *fmt)
{
const char *array[4], *s;
const struct dentry *p;
int depth;
int i, n;
switch (fmt[1]) {
case '2': case '3': case '4':
depth = fmt[1] - '0';
break;
default:
depth = 1;
}
rcu_read_lock();
for (i = 0; i < depth; i++, d = p) {
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, d, spec)) {
rcu_read_unlock();
return buf;
}
locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-24 05:07:29 +08:00
p = READ_ONCE(d->d_parent);
array[i] = READ_ONCE(d->d_name.name);
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
if (p == d) {
if (i)
array[i] = "";
i++;
break;
}
}
s = array[--i];
for (n = 0; n != spec.precision; n++, buf++) {
char c = *s++;
if (!c) {
if (!i)
break;
c = '/';
s = array[--i];
}
if (buf < end)
*buf = c;
}
rcu_read_unlock();
lib/vsprintf.c: pull out padding code from dentry_name() Pull out the logic in dentry_name() which handles field width space padding, in preparation for reusing it from string(). Rename the widen() helper to move_right(), since it is used for handling the !(flags & LEFT) case. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:28 +08:00
return widen_string(buf, n, end, spec);
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
}
vsprintf: Prevent crash when dereferencing invalid pointers for %pD Commit 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") prevents most crash except for %pD. There is an additional pointer dereferencing before dentry_name. At least, vma->file can be NULL and be passed to printk %pD in print_bad_pte, which can cause crash. This patch fixes it with introducing a new file_dentry_name. Link: http://lkml.kernel.org/r/20190809012457.56685-1-justin.he@arm.com Fixes: 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") To: Geert Uytterhoeven <geert+renesas@glider.be> To: Thomas Gleixner <tglx@linutronix.de> To: Andy Shevchenko <andriy.shevchenko@linux.intel.com> To: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Shuah Khan <shuah@kernel.org> Cc: "Tobin C. Harding" <tobin@kernel.org> Signed-off-by: Jia He <justin.he@arm.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-08-09 09:24:56 +08:00
static noinline_for_stack
char *file_dentry_name(char *buf, char *end, const struct file *f,
struct printf_spec spec, const char *fmt)
{
if (check_pointer(&buf, end, f, spec))
return buf;
return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
}
lib/vsprintf: add %*pg format specifier This allow to directly print block_device name. Currently one should use bdevname() with temporal char buffer. This is very ineffective because bloat stack usage for deep IO call-traces Example: %pg -> sda, sda1 or loop0p1 [AV: fixed a minor braino - position updates should not be dependent upon having reached the of buffer] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-13 20:31:35 +08:00
#ifdef CONFIG_BLOCK
static noinline_for_stack
char *bdev_name(char *buf, char *end, struct block_device *bdev,
struct printf_spec spec, const char *fmt)
{
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
struct gendisk *hd;
if (check_pointer(&buf, end, bdev, spec))
return buf;
hd = bdev->bd_disk;
lib/vsprintf: add %*pg format specifier This allow to directly print block_device name. Currently one should use bdevname() with temporal char buffer. This is very ineffective because bloat stack usage for deep IO call-traces Example: %pg -> sda, sda1 or loop0p1 [AV: fixed a minor braino - position updates should not be dependent upon having reached the of buffer] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-13 20:31:35 +08:00
buf = string(buf, end, hd->disk_name, spec);
if (bdev->bd_part->partno) {
if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
if (buf < end)
*buf = 'p';
buf++;
}
buf = number(buf, end, bdev->bd_part->partno, spec);
}
return buf;
}
#endif
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *symbol_string(char *buf, char *end, void *ptr,
vsprintf: Add extension %pSR - print_symbol replacement print_symbol takes a long and converts it to a function name and offset. %pS does something similar, but doesn't translate the address via __builtin_extract_return_addr. %pSR does the translation. This will enable replacing multiple calls like printk(...); printk_symbol(addr); printk("\n"); with a single non-interleavable in dmesg printk("... %pSR\n", (void *)addr); Update documentation too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-13 02:18:50 +08:00
struct printf_spec spec, const char *fmt)
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
{
vsprintf: Add extension %pSR - print_symbol replacement print_symbol takes a long and converts it to a function name and offset. %pS does something similar, but doesn't translate the address via __builtin_extract_return_addr. %pSR does the translation. This will enable replacing multiple calls like printk(...); printk_symbol(addr); printk("\n"); with a single non-interleavable in dmesg printk("... %pSR\n", (void *)addr); Update documentation too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-13 02:18:50 +08:00
unsigned long value;
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
#ifdef CONFIG_KALLSYMS
char sym[KSYM_SYMBOL_LEN];
vsprintf: Add extension %pSR - print_symbol replacement print_symbol takes a long and converts it to a function name and offset. %pS does something similar, but doesn't translate the address via __builtin_extract_return_addr. %pSR does the translation. This will enable replacing multiple calls like printk(...); printk_symbol(addr); printk("\n"); with a single non-interleavable in dmesg printk("... %pSR\n", (void *)addr); Update documentation too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-13 02:18:50 +08:00
#endif
if (fmt[1] == 'R')
ptr = __builtin_extract_return_addr(ptr);
value = (unsigned long)ptr;
#ifdef CONFIG_KALLSYMS
if (*fmt == 'B')
vsprintf: Introduce %pB format specifier The %pB format specifier is for stack backtrace. Its handler sprint_backtrace() does symbol lookup using (address-1) to ensure the address will not point outside of the function. If there is a tail-call to the function marked "noreturn", gcc optimized out the code after the call then causes saved return address points outside of the function (i.e. the start of the next function), so pollutes call trace somewhat. This patch adds the %pB printk mechanism that allows architecture call-trace printout functions to improve backtrace printouts. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arch@vger.kernel.org LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-24 10:42:29 +08:00
sprint_backtrace(sym, value);
lib/vsprintf: Remove support for %pF and %pf in favour of %pS and %ps %pS and %ps are now the preferred conversion specifiers to print function names. The functionality is equivalent; remove the old, deprecated %pF and %pf support. Depends-on: commit 2d44d165e939 ("scsi: lpfc: Convert existing %pf users to %ps") Depends-on: commit b295c3e39c13 ("tools lib traceevent: Convert remaining %p[fF] users to %p[sS]") Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:14 +08:00
else if (*fmt != 's')
vsprintf: introduce %pf format specifier A printf format specifier which would allow us to print a pure function name has been suggested by Andrew Morton a couple of months ago. The current %pF is very convenient to print a function symbol, but often we only want to print the name of the function, without its asm offset. That's what %pf does in this patch. The lowecase f has been chosen for its intuitive meaning of a 'weak kind of %pF'. The support for this new format would be welcome by the tracing code where the need to print pure function names is often needed. This is also true for other parts of the kernel: $ git-grep -E "kallsyms_lookup\(.+?\)" arch/blackfin/kernel/traps.c: symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf); arch/powerpc/xmon/xmon.c: name = kallsyms_lookup(pc, &size, &offset, NULL, tmpstr); arch/sh/kernel/cpu/sh5/unwind.c: sym = kallsyms_lookup(pc, NULL, &offset, NULL, namebuf); arch/x86/kernel/ftrace.c: kallsyms_lookup((unsigned long) syscall, NULL, NULL, NULL, str); kernel/kprobes.c: sym = kallsyms_lookup((unsigned long)p->addr, NULL, kernel/lockdep.c: return kallsyms_lookup((unsigned long)key, NULL, NULL, NULL, str); kernel/trace/ftrace.c: kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); kernel/trace/ftrace.c: kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); kernel/trace/ftrace.c: kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str); kernel/trace/ftrace.c: kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); kernel/trace/ftrace.c: kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); kernel/trace/ftrace.c: kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); kernel/trace/ftrace.c: kallsyms_lookup(*ptr, NULL, NULL, NULL, str); kernel/trace/trace_functions.c: kallsyms_lookup(ip, NULL, NULL, NULL, str); kernel/trace/trace_output.c: kallsyms_lookup(address, NULL, NULL, NULL, str); Changes in v2: - Add the explanation of the %pf role for vsnprintf() and bstr_printf() - Change the comments by dropping the "asm offset" notion and only define the %pf against the actual function offset notion. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Zhaolei <zhaolei@cn.fujitsu.com> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <20090415154817.GC5989@nowhere> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-15 23:48:18 +08:00
sprint_symbol(sym, value);
else
vsprintf: fix %ps on non symbols when using kallsyms Using %ps in a printk format will sometimes fail silently and print the empty string if the address passed in does not match a symbol that kallsyms knows about. But using %pS will fall back to printing the full address if kallsyms can't find the symbol. Make %ps act the same as %pS by falling back to printing the address. While we're here also make %ps print the module that a symbol comes from so that it matches what %pS already does. Take this simple function for example (in a module): static void test_printk(void) { int test; pr_info("with pS: %pS\n", &test); pr_info("with ps: %ps\n", &test); } Before this patch: with pS: 0xdff7df44 with ps: After this patch: with pS: 0xdff7df44 with ps: 0xdff7df44 Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-30 06:07:33 +08:00
sprint_symbol_no_offset(sym, value);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, sym, spec);
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
#else
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
return special_hex_number(buf, end, value, sizeof(void *));
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
#endif
}
lib/vsprintf: Make strspec global There are places where default specification to print strings is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-3-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:05 +08:00
static const struct printf_spec default_str_spec = {
.field_width = -1,
.precision = -1,
};
lib/vsprintf: Make flag_spec global There are places where default specification to print flags as number is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-4-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:06 +08:00
static const struct printf_spec default_flag_spec = {
.base = 16,
.precision = -1,
.flags = SPECIAL | SMALL,
};
lib/vsprintf: Make dec_spec global There are places where default specification to print decimal numbers is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-2-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:04 +08:00
static const struct printf_spec default_dec_spec = {
.base = 10,
.precision = -1,
};
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
static const struct printf_spec default_dec02_spec = {
.base = 10,
.field_width = 2,
.precision = -1,
.flags = ZEROPAD,
};
static const struct printf_spec default_dec04_spec = {
.base = 10,
.field_width = 4,
.precision = -1,
.flags = ZEROPAD,
};
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *resource_string(char *buf, char *end, struct resource *res,
struct printf_spec spec, const char *fmt)
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
{
#ifndef IO_RSRC_PRINTK_SIZE
vsprintf: fix io/mem resource width The leading "0x" consumes field width, so leave space for it in addition to the 4 or 8 hex digits. This means we'll print "0x0000-0x01df" rather than "0x00-0x1df", for example. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:29 +08:00
#define IO_RSRC_PRINTK_SIZE 6
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
#endif
#ifndef MEM_RSRC_PRINTK_SIZE
vsprintf: fix io/mem resource width The leading "0x" consumes field width, so leave space for it in addition to the 4 or 8 hex digits. This means we'll print "0x0000-0x01df" rather than "0x00-0x1df", for example. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:29 +08:00
#define MEM_RSRC_PRINTK_SIZE 10
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
#endif
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
static const struct printf_spec io_spec = {
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
.base = 16,
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
.field_width = IO_RSRC_PRINTK_SIZE,
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
.precision = -1,
.flags = SPECIAL | SMALL | ZEROPAD,
};
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
static const struct printf_spec mem_spec = {
.base = 16,
.field_width = MEM_RSRC_PRINTK_SIZE,
.precision = -1,
.flags = SPECIAL | SMALL | ZEROPAD,
};
resource: add bus number support Add support for bus number resources. This is for bridges with a range of bus numbers behind them. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2010-03-06 01:47:42 +08:00
static const struct printf_spec bus_spec = {
.base = 16,
.field_width = 2,
.precision = -1,
.flags = SMALL | ZEROPAD,
};
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
static const struct printf_spec str_spec = {
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
.field_width = -1,
.precision = 10,
.flags = LEFT,
};
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
* 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
resource: add window support Add support for resource windows. This is for bridge resources, i.e., regions where a bridge forwards transactions from the primary to the secondary side. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2010-03-06 01:47:47 +08:00
#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
char *p = sym, *pend = sym + sizeof(sym);
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
int decode = (fmt[0] == 'R') ? 1 : 0;
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
const struct printf_spec *specp;
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, res, spec))
return buf;
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
*p++ = '[';
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
if (res->flags & IORESOURCE_IO) {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "io ", str_spec);
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
specp = &io_spec;
} else if (res->flags & IORESOURCE_MEM) {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "mem ", str_spec);
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
specp = &mem_spec;
} else if (res->flags & IORESOURCE_IRQ) {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "irq ", str_spec);
lib/vsprintf: Make dec_spec global There are places where default specification to print decimal numbers is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-2-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:04 +08:00
specp = &default_dec_spec;
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
} else if (res->flags & IORESOURCE_DMA) {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "dma ", str_spec);
lib/vsprintf: Make dec_spec global There are places where default specification to print decimal numbers is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-2-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:04 +08:00
specp = &default_dec_spec;
resource: add bus number support Add support for bus number resources. This is for bridges with a range of bus numbers behind them. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2010-03-06 01:47:42 +08:00
} else if (res->flags & IORESOURCE_BUS) {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "bus ", str_spec);
resource: add bus number support Add support for bus number resources. This is for bridges with a range of bus numbers behind them. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2010-03-06 01:47:42 +08:00
specp = &bus_spec;
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
} else {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "??? ", str_spec);
vsprintf: move %pR resource printf_specs off the stack This adds separate I/O and memory specs, so we don't have to change the field width in a shared spec, which then lets us make all the specs const and static, since they never change. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 01:47:37 +08:00
specp = &mem_spec;
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
decode = 0;
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
}
vsprintf: Add support for IORESOURCE_UNSET in %pR Sometimes we have a struct resource where we know the type (MEM/IO/etc.) and the size, but we haven't assigned address space for it. The IORESOURCE_UNSET flag is a way to indicate this situation. For these "unset" resources, the start address is meaningless, so print only the size, e.g., - pci 0000:0c:00.0: reg 184: [mem 0x00000000-0x00001fff 64bit] + pci 0000:0c:00.0: reg 184: [mem size 0x2000 64bit] For %pr (printing with raw flags), we still print the address range, because %pr is mostly used for debugging anyway. Thanks to Fengguang Wu <fengguang.wu@intel.com> for suggesting resource_size(). Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-27 02:25:56 +08:00
if (decode && res->flags & IORESOURCE_UNSET) {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, "size ", str_spec);
vsprintf: Add support for IORESOURCE_UNSET in %pR Sometimes we have a struct resource where we know the type (MEM/IO/etc.) and the size, but we haven't assigned address space for it. The IORESOURCE_UNSET flag is a way to indicate this situation. For these "unset" resources, the start address is meaningless, so print only the size, e.g., - pci 0000:0c:00.0: reg 184: [mem 0x00000000-0x00001fff 64bit] + pci 0000:0c:00.0: reg 184: [mem size 0x2000 64bit] For %pr (printing with raw flags), we still print the address range, because %pr is mostly used for debugging anyway. Thanks to Fengguang Wu <fengguang.wu@intel.com> for suggesting resource_size(). Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-27 02:25:56 +08:00
p = number(p, pend, resource_size(res), *specp);
} else {
p = number(p, pend, res->start, *specp);
if (res->start != res->end) {
*p++ = '-';
p = number(p, pend, res->end, *specp);
}
vsprintf: add %pR support for IRQ and DMA resources Print addresses (IO port numbers and memory addresses) in hex, but print others (IRQs and DMA channels) in decimal. Only print the end if it's different from the start. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:34 +08:00
}
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
if (decode) {
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
if (res->flags & IORESOURCE_MEM_64)
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, " 64bit", str_spec);
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
if (res->flags & IORESOURCE_PREFETCH)
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, " pref", str_spec);
resource: add window support Add support for resource windows. This is for bridge resources, i.e., regions where a bridge forwards transactions from the primary to the secondary side. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2010-03-06 01:47:47 +08:00
if (res->flags & IORESOURCE_WINDOW)
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, " window", str_spec);
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
if (res->flags & IORESOURCE_DISABLED)
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, " disabled", str_spec);
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
} else {
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
p = string_nocheck(p, pend, " flags ", str_spec);
lib/vsprintf: Make flag_spec global There are places where default specification to print flags as number is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-4-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:06 +08:00
p = number(p, pend, res->flags, default_flag_spec);
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
}
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
*p++ = ']';
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
*p = '\0';
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, sym, spec);
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
}
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
static noinline_for_stack
char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
const char *fmt)
{
sprintf: hex_string(): fix comment hex_string() had a typo in a comment. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-29 03:47:39 +08:00
int i, len = 1; /* if we pass '%ph[CDN]', field width remains
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
negative value, fallback to the default */
char separator;
if (spec.field_width == 0)
/* nothing to print */
return buf;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, addr, spec))
return buf;
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
switch (fmt[1]) {
case 'C':
separator = ':';
break;
case 'D':
separator = '-';
break;
case 'N':
separator = 0;
break;
default:
separator = ' ';
break;
}
if (spec.field_width > 0)
len = min_t(int, spec.field_width, 64);
lib/vsprintf.c: fix potential NULL deref in hex_string The helper hex_string() is broken in two ways. First, it doesn't increment buf regardless of whether there is room to print, so callers such as kasprintf() that try to probe the correct storage to allocate will get a too small return value. But even worse, kasprintf() (and likely anyone else trying to find the size of the result) pass NULL for buf and 0 for size, so we also have end == NULL. But this means that the end-1 in hex_string() is (char*)-1, so buf < end-1 is true and we get a NULL pointer deref. I double-checked this with a trivial kernel module that just did a kasprintf(GFP_KERNEL, "%14ph", "CrashBoomBang"). Nobody seems to be using %ph with kasprintf, but we might as well fix it before it hits someone. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:23 +08:00
for (i = 0; i < len; ++i) {
if (buf < end)
*buf = hex_asc_hi(addr[i]);
++buf;
if (buf < end)
*buf = hex_asc_lo(addr[i]);
++buf;
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
lib/vsprintf.c: fix potential NULL deref in hex_string The helper hex_string() is broken in two ways. First, it doesn't increment buf regardless of whether there is room to print, so callers such as kasprintf() that try to probe the correct storage to allocate will get a too small return value. But even worse, kasprintf() (and likely anyone else trying to find the size of the result) pass NULL for buf and 0 for size, so we also have end == NULL. But this means that the end-1 in hex_string() is (char*)-1, so buf < end-1 is true and we get a NULL pointer deref. I double-checked this with a trivial kernel module that just did a kasprintf(GFP_KERNEL, "%14ph", "CrashBoomBang"). Nobody seems to be using %ph with kasprintf, but we might as well fix it before it hits someone. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:23 +08:00
if (separator && i != len - 1) {
if (buf < end)
*buf = separator;
++buf;
}
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
}
return buf;
}
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
static noinline_for_stack
char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
struct printf_spec spec, const char *fmt)
{
const int CHUNKSZ = 32;
int nr_bits = max_t(int, spec.field_width, 0);
int i, chunksz;
bool first = true;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, bitmap, spec))
return buf;
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
/* reused to print numbers */
spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
chunksz = nr_bits & (CHUNKSZ - 1);
if (chunksz == 0)
chunksz = CHUNKSZ;
i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
for (; i >= 0; i -= CHUNKSZ) {
u32 chunkmask, val;
int word, bit;
chunkmask = ((1ULL << chunksz) - 1);
word = i / BITS_PER_LONG;
bit = i % BITS_PER_LONG;
val = (bitmap[word] >> bit) & chunkmask;
if (!first) {
if (buf < end)
*buf = ',';
buf++;
}
first = false;
spec.field_width = DIV_ROUND_UP(chunksz, 4);
buf = number(buf, end, val, spec);
chunksz = CHUNKSZ;
}
return buf;
}
static noinline_for_stack
char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
struct printf_spec spec, const char *fmt)
{
int nr_bits = max_t(int, spec.field_width, 0);
/* current bit is 'cur', most recently seen range is [rbot, rtop] */
int cur, rbot, rtop;
bool first = true;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, bitmap, spec))
return buf;
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
rbot = cur = find_first_bit(bitmap, nr_bits);
while (cur < nr_bits) {
rtop = cur;
cur = find_next_bit(bitmap, nr_bits, cur + 1);
if (cur < nr_bits && cur <= rtop + 1)
continue;
if (!first) {
if (buf < end)
*buf = ',';
buf++;
}
first = false;
lib/vsprintf: Make dec_spec global There are places where default specification to print decimal numbers is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-2-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:04 +08:00
buf = number(buf, end, rbot, default_dec_spec);
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
if (rbot < rtop) {
if (buf < end)
*buf = '-';
buf++;
lib/vsprintf: Make dec_spec global There are places where default specification to print decimal numbers is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-2-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:04 +08:00
buf = number(buf, end, rtop, default_dec_spec);
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
}
rbot = cur;
}
return buf;
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *mac_address_string(char *buf, char *end, u8 *addr,
struct printf_spec spec, const char *fmt)
printk: add %pM format specifier for MAC addresses Add format specifiers for printing out six colon-separated bytes: MAC addresses (%pM): xx:xx:xx:xx:xx:xx %#pM is also supported and omits the colon separators. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 06:47:12 +08:00
{
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
printk: add %pM format specifier for MAC addresses Add format specifiers for printing out six colon-separated bytes: MAC addresses (%pM): xx:xx:xx:xx:xx:xx %#pM is also supported and omits the colon separators. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 06:47:12 +08:00
char *p = mac_addr;
int i;
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
char separator;
vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:23 +08:00
bool reversed = false;
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, addr, spec))
return buf;
vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:23 +08:00
switch (fmt[1]) {
case 'F':
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
separator = '-';
vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:23 +08:00
break;
case 'R':
reversed = true;
/* fall through */
default:
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
separator = ':';
vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:23 +08:00
break;
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
}
printk: add %pM format specifier for MAC addresses Add format specifiers for printing out six colon-separated bytes: MAC addresses (%pM): xx:xx:xx:xx:xx:xx %#pM is also supported and omits the colon separators. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 06:47:12 +08:00
for (i = 0; i < 6; i++) {
vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:23 +08:00
if (reversed)
p = hex_byte_pack(p, addr[5 - i]);
else
p = hex_byte_pack(p, addr[i]);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
if (fmt[0] == 'M' && i != 5)
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
*p++ = separator;
printk: add %pM format specifier for MAC addresses Add format specifiers for printing out six colon-separated bytes: MAC addresses (%pM): xx:xx:xx:xx:xx:xx %#pM is also supported and omits the colon separators. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 06:47:12 +08:00
}
*p = '\0';
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, mac_addr, spec);
printk: add %pM format specifier for MAC addresses Add format specifiers for printing out six colon-separated bytes: MAC addresses (%pM): xx:xx:xx:xx:xx:xx %#pM is also supported and omits the colon separators. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 06:47:12 +08:00
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *ip4_string(char *p, const u8 *addr, const char *fmt)
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
{
int i;
lib/vsprintf.c: Add IPV4 options %pI4[hnbl] for host, network, big and little endian This should allow the removal of the #defines and uses of NIPQUAD and NIPQUAD_FMT Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-14 12:23:30 +08:00
bool leading_zeros = (fmt[0] == 'i');
int index;
int step;
switch (fmt[2]) {
case 'h':
#ifdef __BIG_ENDIAN
index = 0;
step = 1;
#else
index = 3;
step = -1;
#endif
break;
case 'l':
index = 3;
step = -1;
break;
case 'n':
case 'b':
default:
index = 0;
step = 1;
break;
}
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
for (i = 0; i < 4; i++) {
lib/vsprintf.c: even faster binary to decimal conversion The most expensive part of decimal conversion is the divisions by 10 (albeit done using reciprocal multiplication with appropriately chosen constants). I decided to see if one could eliminate around half of these multiplications by emitting two digits at a time, at the cost of a 200 byte lookup table, and it does indeed seem like there is something to be gained, especially on 64 bits. Microbenchmarking shows improvements ranging from -50% (for numbers uniformly distributed in [0, 2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a more realistic distribution). On a larger scale, perf shows that top, one of the big consumers of /proc data, uses 0.5-1.0% fewer cpu cycles. I had to jump through some hoops to get the 32 bit code to compile and run on my 64 bit machine, so I'm not sure how relevant these numbers are, but just for comparison the microbenchmark showed improvements between -30% and -10%. The bloat-o-meter costs are around 150 bytes (the generated code is a little smaller, so it's not the full 200 bytes) on both 32 and 64 bit. I'm aware that extra cache misses won't show up in a microbenchmark as used above, but on the other hand decimal conversions often happen in bulk (for example in the case of top). I have of course tested that the new code generates the same output as the old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9 'random' numbers in-between. Test and verification code on github: https://github.com/Villemoes/dec. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Tested-by: Jeff Epler <jepler@unpythonic.net> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 03:43:22 +08:00
char temp[4] __aligned(2); /* hold each IP quad in reverse order */
vsprintf: further optimize decimal conversion Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01 07:26:08 +08:00
int digits = put_dec_trunc8(temp, addr[index]) - temp;
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
if (leading_zeros) {
if (digits < 3)
*p++ = '0';
if (digits < 2)
*p++ = '0';
}
/* reverse the digits in the quad */
while (digits--)
*p++ = temp[digits];
if (i < 3)
*p++ = '.';
lib/vsprintf.c: Add IPV4 options %pI4[hnbl] for host, network, big and little endian This should allow the removal of the #defines and uses of NIPQUAD and NIPQUAD_FMT Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-14 12:23:30 +08:00
index += step;
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
}
*p = '\0';
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
return p;
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *ip6_compressed_string(char *p, const char *addr)
printk: add %p6 format specifier for IPv6 addresses Takes a pointer to a IPv6 address and formats it in the usual colon-separated hex format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx Each 16 bit word is printed in network-endian byteorder. %#p6 is also supported and will omit the colons. %p6 is a replacement for NIP6_FMT and NIP6() %#p6 is a replacement for NIP6_SEQFMT and NIP6() Note that NIP6() took a struct in6_addr whereas this takes a pointer to a struct in6_addr. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 07:04:44 +08:00
{
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int i, j, range;
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
unsigned char zerolength[8];
int longest = 1;
int colonpos = -1;
u16 word;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
u8 hi, lo;
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
bool needcolon = false;
lib/vsprintf.c: Avoid possible unaligned accesses in %pI6c Jens Rosenboom noticed that a possibly unaligned const char* is cast to a const struct in6_addr *. Avoid this at the cost of a struct in6_addr copy on the stack. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-18 21:04:06 +08:00
bool useIPv4;
struct in6_addr in6;
memcpy(&in6, addr, sizeof(struct in6_addr));
useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
memset(zerolength, 0, sizeof(zerolength));
if (useIPv4)
range = 6;
else
range = 8;
/* find position of longest 0 run */
for (i = 0; i < range; i++) {
for (j = i; j < range; j++) {
lib/vsprintf.c: Avoid possible unaligned accesses in %pI6c Jens Rosenboom noticed that a possibly unaligned const char* is cast to a const struct in6_addr *. Avoid this at the cost of a struct in6_addr copy on the stack. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-18 21:04:06 +08:00
if (in6.s6_addr16[j] != 0)
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
break;
zerolength[i]++;
}
}
for (i = 0; i < range; i++) {
if (zerolength[i] > longest) {
longest = zerolength[i];
colonpos = i;
}
}
vsprintf: Update %pI6c to not compress a single 0 RFC 5952 (http://tools.ietf.org/html/rfc5952) mandates that 2 or more consecutive 0's are required before using :: compression. Update ip6_compressed_string to match the RFC and update the http reference as well. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-10 02:23:37 +08:00
if (longest == 1) /* don't compress a single 0 */
colonpos = -1;
printk: add %p6 format specifier for IPv6 addresses Takes a pointer to a IPv6 address and formats it in the usual colon-separated hex format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx Each 16 bit word is printed in network-endian byteorder. %#p6 is also supported and will omit the colons. %p6 is a replacement for NIP6_FMT and NIP6() %#p6 is a replacement for NIP6_SEQFMT and NIP6() Note that NIP6() took a struct in6_addr whereas this takes a pointer to a struct in6_addr. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 07:04:44 +08:00
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
/* emit address */
for (i = 0; i < range; i++) {
if (i == colonpos) {
if (needcolon || i == 0)
*p++ = ':';
*p++ = ':';
needcolon = false;
i += longest - 1;
continue;
}
if (needcolon) {
*p++ = ':';
needcolon = false;
}
/* hex u16 without leading 0s */
lib/vsprintf.c: Avoid possible unaligned accesses in %pI6c Jens Rosenboom noticed that a possibly unaligned const char* is cast to a const struct in6_addr *. Avoid this at the cost of a struct in6_addr copy on the stack. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-18 21:04:06 +08:00
word = ntohs(in6.s6_addr16[i]);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
hi = word >> 8;
lo = word & 0xff;
if (hi) {
if (hi > 0x0f)
lib: rename pack_hex_byte() to hex_byte_pack() As suggested by Andrew Morton in [1] there is better to have most significant part first in the function name. [1] https://lkml.org/lkml/2011/9/20/22 There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "John W. Linville" <linville@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:41 +08:00
p = hex_byte_pack(p, hi);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
else
*p++ = hex_asc_lo(hi);
lib: rename pack_hex_byte() to hex_byte_pack() As suggested by Andrew Morton in [1] there is better to have most significant part first in the function name. [1] https://lkml.org/lkml/2011/9/20/22 There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "John W. Linville" <linville@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:41 +08:00
p = hex_byte_pack(p, lo);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
}
vsprintf: reduce code size by avoiding extra check No functional change, just refactor the code so that it avoid checking "if (hi)" two times in a sequence, taking advantage of previous check made. It also reduces code size: text data bss dec hex filename 15726 0 8 15734 3d76 vsprintf.o (ex lib/lib.a-BEFORE) 15710 0 8 15718 3d66 vsprintf.o (ex lib/lib.a-AFTER) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
else if (lo > 0x0f)
lib: rename pack_hex_byte() to hex_byte_pack() As suggested by Andrew Morton in [1] there is better to have most significant part first in the function name. [1] https://lkml.org/lkml/2011/9/20/22 There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "John W. Linville" <linville@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:41 +08:00
p = hex_byte_pack(p, lo);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
else
*p++ = hex_asc_lo(lo);
needcolon = true;
}
if (useIPv4) {
if (needcolon)
*p++ = ':';
lib/vsprintf.c: Add IPV4 options %pI4[hnbl] for host, network, big and little endian This should allow the removal of the #defines and uses of NIPQUAD and NIPQUAD_FMT Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-14 12:23:30 +08:00
p = ip4_string(p, &in6.s6_addr[12], "I4");
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
}
*p = '\0';
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
return p;
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *ip6_string(char *p, const char *addr, const char *fmt)
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
{
int i;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
printk: add %p6 format specifier for IPv6 addresses Takes a pointer to a IPv6 address and formats it in the usual colon-separated hex format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx Each 16 bit word is printed in network-endian byteorder. %#p6 is also supported and will omit the colons. %p6 is a replacement for NIP6_FMT and NIP6() %#p6 is a replacement for NIP6_SEQFMT and NIP6() Note that NIP6() took a struct in6_addr whereas this takes a pointer to a struct in6_addr. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 07:04:44 +08:00
for (i = 0; i < 8; i++) {
lib: rename pack_hex_byte() to hex_byte_pack() As suggested by Andrew Morton in [1] there is better to have most significant part first in the function name. [1] https://lkml.org/lkml/2011/9/20/22 There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "John W. Linville" <linville@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 08:12:41 +08:00
p = hex_byte_pack(p, *addr++);
p = hex_byte_pack(p, *addr++);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
if (fmt[0] == 'I' && i != 7)
printk: add %p6 format specifier for IPv6 addresses Takes a pointer to a IPv6 address and formats it in the usual colon-separated hex format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx Each 16 bit word is printed in network-endian byteorder. %#p6 is also supported and will omit the colons. %p6 is a replacement for NIP6_FMT and NIP6() %#p6 is a replacement for NIP6_SEQFMT and NIP6() Note that NIP6() took a struct in6_addr whereas this takes a pointer to a struct in6_addr. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 07:04:44 +08:00
*p++ = ':';
}
*p = '\0';
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
return p;
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *ip6_addr_string(char *buf, char *end, const u8 *addr,
struct printf_spec spec, const char *fmt)
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
{
char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
if (fmt[0] == 'I' && fmt[2] == 'c')
lib/vsprintf.c: Avoid possible unaligned accesses in %pI6c Jens Rosenboom noticed that a possibly unaligned const char* is cast to a const struct in6_addr *. Avoid this at the cost of a struct in6_addr copy on the stack. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-18 21:04:06 +08:00
ip6_compressed_string(ip6_addr, addr);
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
else
lib/vsprintf.c: Avoid possible unaligned accesses in %pI6c Jens Rosenboom noticed that a possibly unaligned const char* is cast to a const struct in6_addr *. Avoid this at the cost of a struct in6_addr copy on the stack. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-18 21:04:06 +08:00
ip6_string(ip6_addr, addr, fmt);
printk: add %p6 format specifier for IPv6 addresses Takes a pointer to a IPv6 address and formats it in the usual colon-separated hex format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx Each 16 bit word is printed in network-endian byteorder. %#p6 is also supported and will omit the colons. %p6 is a replacement for NIP6_FMT and NIP6() %#p6 is a replacement for NIP6_SEQFMT and NIP6() Note that NIP6() took a struct in6_addr whereas this takes a pointer to a struct in6_addr. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 07:04:44 +08:00
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, ip6_addr, spec);
printk: add %p6 format specifier for IPv6 addresses Takes a pointer to a IPv6 address and formats it in the usual colon-separated hex format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx Each 16 bit word is printed in network-endian byteorder. %#p6 is also supported and will omit the colons. %p6 is a replacement for NIP6_FMT and NIP6() %#p6 is a replacement for NIP6_SEQFMT and NIP6() Note that NIP6() took a struct in6_addr whereas this takes a pointer to a struct in6_addr. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 07:04:44 +08:00
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *ip4_addr_string(char *buf, char *end, const u8 *addr,
struct printf_spec spec, const char *fmt)
printk: add %I4, %I6, %i4, %i6 format specifiers For use in printing IPv4, or IPv6 addresses in the usual way: %i4 and %I4 are currently equivalent and print the address in dot-separated decimal x.x.x.x %I6 prints 16-bit network order hex with colon separators: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx %i6 omits the colons. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-30 03:49:58 +08:00
{
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
char ip4_addr[sizeof("255.255.255.255")];
printk: add %I4, %I6, %i4, %i6 format specifiers For use in printing IPv4, or IPv6 addresses in the usual way: %i4 and %I4 are currently equivalent and print the address in dot-separated decimal x.x.x.x %I6 prints 16-bit network order hex with colon separators: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx %i6 omits the colons. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-30 03:49:58 +08:00
lib/vsprintf.c: Add IPV4 options %pI4[hnbl] for host, network, big and little endian This should allow the removal of the #defines and uses of NIPQUAD and NIPQUAD_FMT Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-14 12:23:30 +08:00
ip4_string(ip4_addr, addr, fmt);
printk: add %I4, %I6, %i4, %i6 format specifiers For use in printing IPv4, or IPv6 addresses in the usual way: %i4 and %I4 are currently equivalent and print the address in dot-separated decimal x.x.x.x %I6 prints 16-bit network order hex with colon separators: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx %i6 omits the colons. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-30 03:49:58 +08:00
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, ip4_addr, spec);
printk: add %I4, %I6, %i4, %i6 format specifiers For use in printing IPv4, or IPv6 addresses in the usual way: %i4 and %I4 are currently equivalent and print the address in dot-separated decimal x.x.x.x %I6 prints 16-bit network order hex with colon separators: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx %i6 omits the colons. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-30 03:49:58 +08:00
}
lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier In order to avoid making code that deals with printing both, IPv4 and IPv6 addresses, unnecessary complicated as for example ... if (sa.sa_family == AF_INET6) printk("... %pI6 ...", ..sin6_addr); else printk("... %pI4 ...", ..sin_addr.s_addr); ... it would be better to introduce a format specifier that can deal with those kind of situations internally; just as we have a "struct sockaddr" for generic mapping into "struct sockaddr_in" or "struct sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could reduce the above statement into something like: printk("... %pIS ..", &sockaddr); In case our pointer is NULL, pointer() then deals with that already at an earlier point in time internally. While we're at it, support for both %piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free. Additionally to that, postfix specifiers 'p', 'f' and 's' are supported as suggested and initially implemented in 2009 by Joe Perches [1]. Handling of those additional specifiers orientate on the initial RFC that was proposed. Also we support IPv6 compressed format specified by 'c' and various other IPv4 extensions as stated in the documentation part. Likely, there are many other areas than just SCTP in the kernel to make use of this extension as well. [1] http://patchwork.ozlabs.org/patch/31480/ Signed-off-by: Daniel Borkmann <dborkman@redhat.com> CC: Joe Perches <joe@perches.com> CC: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-29 01:49:39 +08:00
static noinline_for_stack
char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
struct printf_spec spec, const char *fmt)
{
bool have_p = false, have_s = false, have_f = false, have_c = false;
char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
sizeof(":12345") + sizeof("/123456789") +
sizeof("%1234567890")];
char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
const u8 *addr = (const u8 *) &sa->sin6_addr;
char fmt6[2] = { fmt[0], '6' };
u8 off = 0;
fmt++;
while (isalpha(*++fmt)) {
switch (*fmt) {
case 'p':
have_p = true;
break;
case 'f':
have_f = true;
break;
case 's':
have_s = true;
break;
case 'c':
have_c = true;
break;
}
}
if (have_p || have_s || have_f) {
*p = '[';
off = 1;
}
if (fmt6[0] == 'I' && have_c)
p = ip6_compressed_string(ip6_addr + off, addr);
else
p = ip6_string(ip6_addr + off, addr, fmt6);
if (have_p || have_s || have_f)
*p++ = ']';
if (have_p) {
*p++ = ':';
p = number(p, pend, ntohs(sa->sin6_port), spec);
}
if (have_f) {
*p++ = '/';
p = number(p, pend, ntohl(sa->sin6_flowinfo &
IPV6_FLOWINFO_MASK), spec);
}
if (have_s) {
*p++ = '%';
p = number(p, pend, sa->sin6_scope_id, spec);
}
*p = '\0';
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, ip6_addr, spec);
lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier In order to avoid making code that deals with printing both, IPv4 and IPv6 addresses, unnecessary complicated as for example ... if (sa.sa_family == AF_INET6) printk("... %pI6 ...", ..sin6_addr); else printk("... %pI4 ...", ..sin_addr.s_addr); ... it would be better to introduce a format specifier that can deal with those kind of situations internally; just as we have a "struct sockaddr" for generic mapping into "struct sockaddr_in" or "struct sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could reduce the above statement into something like: printk("... %pIS ..", &sockaddr); In case our pointer is NULL, pointer() then deals with that already at an earlier point in time internally. While we're at it, support for both %piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free. Additionally to that, postfix specifiers 'p', 'f' and 's' are supported as suggested and initially implemented in 2009 by Joe Perches [1]. Handling of those additional specifiers orientate on the initial RFC that was proposed. Also we support IPv6 compressed format specified by 'c' and various other IPv4 extensions as stated in the documentation part. Likely, there are many other areas than just SCTP in the kernel to make use of this extension as well. [1] http://patchwork.ozlabs.org/patch/31480/ Signed-off-by: Daniel Borkmann <dborkman@redhat.com> CC: Joe Perches <joe@perches.com> CC: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-29 01:49:39 +08:00
}
static noinline_for_stack
char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
struct printf_spec spec, const char *fmt)
{
bool have_p = false;
char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
char *pend = ip4_addr + sizeof(ip4_addr);
const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
char fmt4[3] = { fmt[0], '4', 0 };
fmt++;
while (isalpha(*++fmt)) {
switch (*fmt) {
case 'p':
have_p = true;
break;
case 'h':
case 'l':
case 'n':
case 'b':
fmt4[2] = *fmt;
break;
}
}
p = ip4_string(ip4_addr, addr, fmt4);
if (have_p) {
*p++ = ':';
p = number(p, pend, ntohs(sa->sin_port), spec);
}
*p = '\0';
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, ip4_addr, spec);
lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier In order to avoid making code that deals with printing both, IPv4 and IPv6 addresses, unnecessary complicated as for example ... if (sa.sa_family == AF_INET6) printk("... %pI6 ...", ..sin6_addr); else printk("... %pI4 ...", ..sin_addr.s_addr); ... it would be better to introduce a format specifier that can deal with those kind of situations internally; just as we have a "struct sockaddr" for generic mapping into "struct sockaddr_in" or "struct sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could reduce the above statement into something like: printk("... %pIS ..", &sockaddr); In case our pointer is NULL, pointer() then deals with that already at an earlier point in time internally. While we're at it, support for both %piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free. Additionally to that, postfix specifiers 'p', 'f' and 's' are supported as suggested and initially implemented in 2009 by Joe Perches [1]. Handling of those additional specifiers orientate on the initial RFC that was proposed. Also we support IPv6 compressed format specified by 'c' and various other IPv4 extensions as stated in the documentation part. Likely, there are many other areas than just SCTP in the kernel to make use of this extension as well. [1] http://patchwork.ozlabs.org/patch/31480/ Signed-off-by: Daniel Borkmann <dborkman@redhat.com> CC: Joe Perches <joe@perches.com> CC: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-29 01:49:39 +08:00
}
vsprintf: Factor out %p[iI] handler as ip_addr_string() Move the non-trivial code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-5-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:44 +08:00
static noinline_for_stack
char *ip_addr_string(char *buf, char *end, const void *ptr,
struct printf_spec spec, const char *fmt)
{
vsprintf: Consolidate handling of unknown pointer specifiers There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:47 +08:00
char *err_fmt_msg;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, ptr, spec))
return buf;
vsprintf: Factor out %p[iI] handler as ip_addr_string() Move the non-trivial code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-5-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:44 +08:00
switch (fmt[1]) {
case '6':
return ip6_addr_string(buf, end, ptr, spec, fmt);
case '4':
return ip4_addr_string(buf, end, ptr, spec, fmt);
case 'S': {
const union {
struct sockaddr raw;
struct sockaddr_in v4;
struct sockaddr_in6 v6;
} *sa = ptr;
switch (sa->raw.sa_family) {
case AF_INET:
return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
case AF_INET6:
return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
default:
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "(einval)", spec);
vsprintf: Factor out %p[iI] handler as ip_addr_string() Move the non-trivial code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-5-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:44 +08:00
}}
}
vsprintf: Consolidate handling of unknown pointer specifiers There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:47 +08:00
err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, err_fmt_msg, spec);
vsprintf: Factor out %p[iI] handler as ip_addr_string() Move the non-trivial code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-5-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:44 +08:00
}
lib/vsprintf: add %*pE[achnops] format specifier This allows user to print a given buffer as an escaped string. The rules are applied according to an optional mix of flags provided by additional format letters. For example, if the given buffer is: 1b 62 20 5c 43 07 22 90 0d 5d The result strings would be: %*pE "\eb \C\a"\220\r]" %*pEhp "\x1bb \C\x07"\x90\x0d]" %*pEa "\e\142\040\\\103\a\042\220\r\135" Please, read Documentation/printk-formats.txt and lib/string_helpers.c kernel documentation to get further information. [akpm@linux-foundation.org: tidy up comment layout, per Joe] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Joe Perches <joe@perches.com> Cc: "John W . Linville" <linville@tuxdriver.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 06:55:18 +08:00
static noinline_for_stack
char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
const char *fmt)
{
bool found = true;
int count = 1;
unsigned int flags = 0;
int len;
if (spec.field_width == 0)
return buf; /* nothing to print */
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, addr, spec))
return buf;
lib/vsprintf: add %*pE[achnops] format specifier This allows user to print a given buffer as an escaped string. The rules are applied according to an optional mix of flags provided by additional format letters. For example, if the given buffer is: 1b 62 20 5c 43 07 22 90 0d 5d The result strings would be: %*pE "\eb \C\a"\220\r]" %*pEhp "\x1bb \C\x07"\x90\x0d]" %*pEa "\e\142\040\\\103\a\042\220\r\135" Please, read Documentation/printk-formats.txt and lib/string_helpers.c kernel documentation to get further information. [akpm@linux-foundation.org: tidy up comment layout, per Joe] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Joe Perches <joe@perches.com> Cc: "John W . Linville" <linville@tuxdriver.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 06:55:18 +08:00
do {
switch (fmt[count++]) {
case 'a':
flags |= ESCAPE_ANY;
break;
case 'c':
flags |= ESCAPE_SPECIAL;
break;
case 'h':
flags |= ESCAPE_HEX;
break;
case 'n':
flags |= ESCAPE_NULL;
break;
case 'o':
flags |= ESCAPE_OCTAL;
break;
case 'p':
flags |= ESCAPE_NP;
break;
case 's':
flags |= ESCAPE_SPACE;
break;
default:
found = false;
break;
}
} while (found);
if (!flags)
flags = ESCAPE_ANY_NP;
len = spec.field_width < 0 ? 1 : spec.field_width;
lib/string_helpers.c: change semantics of string_escape_mem The current semantics of string_escape_mem are inadequate for one of its current users, vsnprintf(). If that is to honour its contract, it must know how much space would be needed for the entire escaped buffer, and string_escape_mem provides no way of obtaining that (short of allocating a large enough buffer (~4 times input string) to let it play with, and that's definitely a big no-no inside vsnprintf). So change the semantics for string_escape_mem to be more snprintf-like: Return the size of the output that would be generated if the destination buffer was big enough, but of course still only write to the part of dst it is allowed to, and (contrary to snprintf) don't do '\0'-termination. It is then up to the caller to detect whether output was truncated and to append a '\0' if desired. Also, we must output partial escape sequences, otherwise a call such as snprintf(buf, 3, "%1pE", "\123") would cause printf to write a \0 to buf[2] but leaving buf[0] and buf[1] with whatever they previously contained. This also fixes a bug in the escaped_string() helper function, which used to unconditionally pass a length of "end-buf" to string_escape_mem(); since the latter doesn't check osz for being insanely large, it would happily write to dst. For example, kasprintf(GFP_KERNEL, "something and then %pE", ...); is an easy way to trigger an oops. In test-string_helpers.c, the -ENOMEM test is replaced with testing for getting the expected return value even if the buffer is too small. We also ensure that nothing is written (by relying on a NULL pointer deref) if the output size is 0 by passing NULL - this has to work for kasprintf("%pE") to work. In net/sunrpc/cache.c, I think qword_add still has the same semantics. Someone should definitely double-check this. In fs/proc/array.c, I made the minimum possible change, but longer-term it should stop poking around in seq_file internals. [andriy.shevchenko@linux.intel.com: simplify qword_add] [andriy.shevchenko@linux.intel.com: add missed curly braces] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:28 +08:00
/*
* string_escape_mem() writes as many characters as it can to
* the given buffer, and returns the total size of the output
* had the buffer been big enough.
*/
buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
lib/vsprintf: add %*pE[achnops] format specifier This allows user to print a given buffer as an escaped string. The rules are applied according to an optional mix of flags provided by additional format letters. For example, if the given buffer is: 1b 62 20 5c 43 07 22 90 0d 5d The result strings would be: %*pE "\eb \C\a"\220\r]" %*pEhp "\x1bb \C\x07"\x90\x0d]" %*pEa "\e\142\040\\\103\a\042\220\r\135" Please, read Documentation/printk-formats.txt and lib/string_helpers.c kernel documentation to get further information. [akpm@linux-foundation.org: tidy up comment layout, per Joe] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Joe Perches <joe@perches.com> Cc: "John W . Linville" <linville@tuxdriver.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 06:55:18 +08:00
return buf;
}
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
static char *va_format(char *buf, char *end, struct va_format *va_fmt,
struct printf_spec spec, const char *fmt)
vsprintf: Factor out %pV handler as va_format() Move the code from the long pointer() function. We are going to improve error handling that will make it more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-6-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:45 +08:00
{
va_list va;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, va_fmt, spec))
return buf;
vsprintf: Factor out %pV handler as va_format() Move the code from the long pointer() function. We are going to improve error handling that will make it more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-6-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:45 +08:00
va_copy(va, *va_fmt->va);
buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
va_end(va);
return buf;
}
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *uuid_string(char *buf, char *end, const u8 *addr,
struct printf_spec spec, const char *fmt)
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
{
lib/uuid.c: introduce a few more generic helpers There are new helpers in this patch: uuid_is_valid checks if a UUID is valid uuid_be_to_bin converts from string to binary (big endian) uuid_le_to_bin converts from string to binary (little endian) They will be used in future, i.e. in the following patches in the series. This also moves the indices arrays to lib/uuid.c to be shared accross modules. [andriy.shevchenko@linux.intel.com: fix typo] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-21 08:01:04 +08:00
char uuid[UUID_STRING_LEN + 1];
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
char *p = uuid;
int i;
uuid: rename uuid types Our "little endian" UUID really is a Wintel GUID, so rename it and its helpers such (guid_t). The big endian UUID is the only true one, so give it the name uuid_t. The uuid_le and uuid_be names are retained for now, but will hopefully go away soon. The exception to that are the _cmp helpers that will be replaced by better primitives ASAP and thus don't get the new names. Also the _to_bin helpers are named to match the better named uuid_parse routine in userspace. Also remove the existing typedef in XFS that's now been superceeded by the generic type name. Signed-off-by: Christoph Hellwig <hch@lst.de> [andy: also update the UUID_LE/UUID_BE macros including fallout] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-17 16:02:48 +08:00
const u8 *index = uuid_index;
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
bool uc = false;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, addr, spec))
return buf;
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
switch (*(++fmt)) {
case 'L':
uc = true; /* fall-through */
case 'l':
uuid: rename uuid types Our "little endian" UUID really is a Wintel GUID, so rename it and its helpers such (guid_t). The big endian UUID is the only true one, so give it the name uuid_t. The uuid_le and uuid_be names are retained for now, but will hopefully go away soon. The exception to that are the _cmp helpers that will be replaced by better primitives ASAP and thus don't get the new names. Also the _to_bin helpers are named to match the better named uuid_parse routine in userspace. Also remove the existing typedef in XFS that's now been superceeded by the generic type name. Signed-off-by: Christoph Hellwig <hch@lst.de> [andy: also update the UUID_LE/UUID_BE macros including fallout] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-17 16:02:48 +08:00
index = guid_index;
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
break;
case 'B':
uc = true;
break;
}
for (i = 0; i < 16; i++) {
lib/vsprintf: simplify UUID printing There are few functions here and there along with type definitions that provide UUID API. This series consolidates everything under one hood and converts current users. This has been tested for a while internally, however it doesn't mean we covered all possible cases (especially accuracy of UUID constants after conversion). So, please test this as much as you can and provide your tag. We appreciate the effort. The ACPI conversion is postponed for now to sort more generic things out first. This patch (of 9): Since we have hex_byte_pack_upper() we may use it directly and avoid second loop. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-21 08:00:54 +08:00
if (uc)
p = hex_byte_pack_upper(p, addr[index[i]]);
else
p = hex_byte_pack(p, addr[index[i]]);
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
switch (i) {
case 3:
case 5:
case 7:
case 9:
*p++ = '-';
break;
}
}
*p = 0;
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
return string_nocheck(buf, end, uuid, spec);
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
}
lib/vsprintf: factor out %pN[F] handler as netdev_bits() Move switch case to the netdev_features_string() and rename it to netdev_bits(). In the future we can extend it as needed. Here we replace the fallback of %pN from '%p' with possible flags to sticter '0x%p' without any flags variation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:20 +08:00
static noinline_for_stack
lib/vsprintf: Hash printed address for netdev bits fallback The handler for "%pN" falls back to printing the raw pointer value when using a different format than the (sole supported) special format "%pNF", potentially leaking sensitive information regarding the kernel layout in memory. Avoid this leak by printing the hashed address instead. Note that there are no in-tree users of the fallback. Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p") Link: http://lkml.kernel.org/r/20181011084249.4520-4-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:49 +08:00
char *netdev_bits(char *buf, char *end, const void *addr,
struct printf_spec spec, const char *fmt)
net: introduce and use netdev_features_t for device features sets v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-15 23:29:55 +08:00
{
lib/vsprintf: factor out %pN[F] handler as netdev_bits() Move switch case to the netdev_features_string() and rename it to netdev_bits(). In the future we can extend it as needed. Here we replace the fallback of %pN from '%p' with possible flags to sticter '0x%p' without any flags variation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:20 +08:00
unsigned long long num;
int size;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, addr, spec))
return buf;
lib/vsprintf: factor out %pN[F] handler as netdev_bits() Move switch case to the netdev_features_string() and rename it to netdev_bits(). In the future we can extend it as needed. Here we replace the fallback of %pN from '%p' with possible flags to sticter '0x%p' without any flags variation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:20 +08:00
switch (fmt[1]) {
case 'F':
num = *(const netdev_features_t *)addr;
size = sizeof(netdev_features_t);
break;
default:
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "(%pN?)", spec);
lib/vsprintf: factor out %pN[F] handler as netdev_bits() Move switch case to the netdev_features_string() and rename it to netdev_bits(). In the future we can extend it as needed. Here we replace the fallback of %pN from '%p' with possible flags to sticter '0x%p' without any flags variation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:20 +08:00
}
net: introduce and use netdev_features_t for device features sets v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-15 23:29:55 +08:00
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
return special_hex_number(buf, end, num, size);
net: introduce and use netdev_features_t for device features sets v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-15 23:29:55 +08:00
}
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
static noinline_for_stack
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
char *address_val(char *buf, char *end, const void *addr,
struct printf_spec spec, const char *fmt)
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
{
unsigned long long num;
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
int size;
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, addr, spec))
return buf;
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
switch (fmt[1]) {
case 'd':
num = *(const dma_addr_t *)addr;
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
size = sizeof(dma_addr_t);
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
break;
case 'p':
default:
num = *(const phys_addr_t *)addr;
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
size = sizeof(phys_addr_t);
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
break;
}
lib/vsprintf: refactor duplicate code to special_hex_number() special_hex_number() is a helper to print a fixed size type in a hex format with '0x' prefix, zero padding, and small letters. In the module we have already several copies of such code. Consolidate them under special_hex_number() helper. There are couple of differences though. It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when printing symbol address, because the asked field width is not enough to care last 2 characters in the string represantation of the pointer. Fixed here. The %pNF specifier used to be allowed with a specific field width, though there is neither any user of it nor mention the possibility in the documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:59:18 +08:00
return special_hex_number(buf, end, num, size);
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
}
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
static noinline_for_stack
char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
{
int year = tm->tm_year + (r ? 0 : 1900);
int mon = tm->tm_mon + (r ? 0 : 1);
buf = number(buf, end, year, default_dec04_spec);
if (buf < end)
*buf = '-';
buf++;
buf = number(buf, end, mon, default_dec02_spec);
if (buf < end)
*buf = '-';
buf++;
return number(buf, end, tm->tm_mday, default_dec02_spec);
}
static noinline_for_stack
char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
{
buf = number(buf, end, tm->tm_hour, default_dec02_spec);
if (buf < end)
*buf = ':';
buf++;
buf = number(buf, end, tm->tm_min, default_dec02_spec);
if (buf < end)
*buf = ':';
buf++;
return number(buf, end, tm->tm_sec, default_dec02_spec);
}
static noinline_for_stack
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
struct printf_spec spec, const char *fmt)
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
{
bool have_t = true, have_d = true;
bool raw = false;
int count = 2;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, tm, spec))
return buf;
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
switch (fmt[count]) {
case 'd':
have_t = false;
count++;
break;
case 't':
have_d = false;
count++;
break;
}
raw = fmt[count] == 'r';
if (have_d)
buf = date_str(buf, end, tm, raw);
if (have_d && have_t) {
/* Respect ISO 8601 */
if (buf < end)
*buf = 'T';
buf++;
}
if (have_t)
buf = time_str(buf, end, tm, raw);
return buf;
}
static noinline_for_stack
char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
const char *fmt)
{
switch (fmt[1]) {
case 'R':
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
default:
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "(%ptR?)", spec);
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
}
}
lib/vsprintf: add %pC{,n,r} format specifiers for clocks Add format specifiers for printing struct clk: - '%pC' or '%pCn': name (Common Clock Framework) or address (legacy clock framework) of the clock, - '%pCr': rate of the clock. [akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:20 +08:00
static noinline_for_stack
char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
const char *fmt)
{
vsprintf: Consolidate handling of unknown pointer specifiers There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:47 +08:00
if (!IS_ENABLED(CONFIG_HAVE_CLK))
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "(%pC?)", spec);
vsprintf: Consolidate handling of unknown pointer specifiers There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:47 +08:00
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, clk, spec))
return buf;
lib/vsprintf: add %pC{,n,r} format specifiers for clocks Add format specifiers for printing struct clk: - '%pC' or '%pCn': name (Common Clock Framework) or address (legacy clock framework) of the clock, - '%pCr': rate of the clock. [akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:20 +08:00
switch (fmt[1]) {
case 'n':
default:
#ifdef CONFIG_COMMON_CLK
return string(buf, end, __clk_get_name(clk), spec);
#else
lib/vsprintf: Reinstate printing of legacy clock IDs When using the legacy clock framework, clock pointers are no longer printed as IDs, as the !CONFIG_COMMON_CLK case was accidentally considered an error case. Fix this by reverting to the old behavior, which allows to distinguish clocks by ID, as the legacy clock framework does not store names with clocks. Fixes: 0b74d4d763fd4ee9 ("vsprintf: Consolidate handling of unknown pointer specifiers") Link: http://lkml.kernel.org/r/20190701140009.23683-1-geert+renesas@glider.be Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-07-01 22:00:09 +08:00
return ptr_to_id(buf, end, clk, spec);
lib/vsprintf: add %pC{,n,r} format specifiers for clocks Add format specifiers for printing struct clk: - '%pC' or '%pCn': name (Common Clock Framework) or address (legacy clock framework) of the clock, - '%pCr': rate of the clock. [akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:20 +08:00
#endif
}
}
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
static
char *format_flags(char *buf, char *end, unsigned long flags,
const struct trace_print_flags *names)
{
unsigned long mask;
for ( ; flags && names->name; names++) {
mask = names->mask;
if ((flags & mask) != mask)
continue;
lib/vsprintf: Make strspec global There are places where default specification to print strings is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-3-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:05 +08:00
buf = string(buf, end, names->name, default_str_spec);
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
flags &= ~mask;
if (flags) {
if (buf < end)
*buf = '|';
buf++;
}
}
if (flags)
lib/vsprintf: Make flag_spec global There are places where default specification to print flags as number is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-4-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:06 +08:00
buf = number(buf, end, flags, default_flag_spec);
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
return buf;
}
static noinline_for_stack
vsprintf: Consolidate handling of unknown pointer specifiers There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:47 +08:00
char *flags_string(char *buf, char *end, void *flags_ptr,
struct printf_spec spec, const char *fmt)
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
{
unsigned long flags;
const struct trace_print_flags *names;
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, flags_ptr, spec))
return buf;
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
switch (fmt[1]) {
case 'p':
flags = *(unsigned long *)flags_ptr;
/* Remove zone id */
flags &= (1UL << NR_PAGEFLAGS) - 1;
names = pageflag_names;
break;
case 'v':
flags = *(unsigned long *)flags_ptr;
names = vmaflag_names;
break;
case 'g':
flags = *(gfp_t *)flags_ptr;
names = gfpflag_names;
break;
default:
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "(%pG?)", spec);
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
}
return format_flags(buf, end, flags, names);
}
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
static noinline_for_stack
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf,
char *end)
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
{
int depth;
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
/* Loop starting from the root node to the current node. */
for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) {
struct fwnode_handle *__fwnode =
fwnode_get_nth_parent(fwnode, depth);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
buf = string(buf, end, fwnode_get_name_prefix(__fwnode),
lib/vsprintf: Make strspec global There are places where default specification to print strings is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-3-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:05 +08:00
default_str_spec);
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
buf = string(buf, end, fwnode_get_name(__fwnode),
lib/vsprintf: Make strspec global There are places where default specification to print strings is in use. Make it global and convert existing users. Link: http://lkml.kernel.org/r/20180216210711.79901-3-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:05 +08:00
default_str_spec);
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
fwnode_handle_put(__fwnode);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
}
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
return buf;
}
static noinline_for_stack
char *device_node_string(char *buf, char *end, struct device_node *dn,
struct printf_spec spec, const char *fmt)
{
char tbuf[sizeof("xxxx") + 1];
const char *p;
int ret;
char *buf_start = buf;
struct property *prop;
bool has_mult, pass;
static const struct printf_spec num_spec = {
.flags = SMALL,
.field_width = -1,
.precision = -1,
.base = 10,
};
struct printf_spec str_spec = spec;
str_spec.field_width = -1;
lib/vsprintf: OF nodes are first and foremost, struct device_nodes Factor out static kobject_string() function that simply calls device_node_string(), and thus remove references to kobjects (as these are struct device_node). Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:17 +08:00
if (fmt[0] != 'F')
return error_string(buf, end, "(%pO?)", spec);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
if (!IS_ENABLED(CONFIG_OF))
vsprintf: Limit the length of inlined error messages The inlined error messages must be used carefully because they need to fit into the given buffer. Handle them using a custom wrapper that makes people aware of the problem. Also define a reasonable hard limit to avoid a completely insane usage. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Link: http://lkml.kernel.org/r/20190417115350.20479-11-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:50 +08:00
return error_string(buf, end, "(%pOF?)", spec);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
if (check_pointer(&buf, end, dn, spec))
return buf;
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
/* simple case without anything any more format specifiers */
fmt++;
if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
fmt = "f";
for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
vsprintf: print OF node name using full_name In preparation to remove the node name pointer from struct device_node, convert the node name print to get the node name from the full name. Reviewed-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-27 21:13:56 +08:00
int precision;
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
if (pass) {
if (buf < end)
*buf = ':';
buf++;
}
switch (*fmt) {
case 'f': /* full_name */
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
buf = fwnode_full_name_string(of_fwnode_handle(dn), buf,
end);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
break;
case 'n': /* name */
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
p = fwnode_get_name(of_fwnode_handle(dn));
vsprintf: print OF node name using full_name In preparation to remove the node name pointer from struct device_node, convert the node name print to get the node name from the full name. Reviewed-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-27 21:13:56 +08:00
precision = str_spec.precision;
str_spec.precision = strchrnul(p, '@') - p;
buf = string(buf, end, p, str_spec);
str_spec.precision = precision;
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
break;
case 'p': /* phandle */
buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
break;
case 'P': /* path-spec */
lib/vsprintf: Make use of fwnode API to obtain node names and separators Instead of implementing our own means of discovering parent nodes, node names or counting how many parents a node has, use the newly added functions in the fwnode API to obtain that information. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:16 +08:00
p = fwnode_get_name(of_fwnode_handle(dn));
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
if (!p[1])
p = "/";
buf = string(buf, end, p, str_spec);
break;
case 'F': /* flags */
tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
tbuf[4] = 0;
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
buf = string_nocheck(buf, end, tbuf, str_spec);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
break;
case 'c': /* major compatible string */
ret = of_property_read_string(dn, "compatible", &p);
if (!ret)
buf = string(buf, end, p, str_spec);
break;
case 'C': /* full compatible string */
has_mult = false;
of_property_for_each_string(dn, "compatible", prop, p) {
if (has_mult)
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
buf = string_nocheck(buf, end, ",", str_spec);
buf = string_nocheck(buf, end, "\"", str_spec);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
buf = string(buf, end, p, str_spec);
vsprintf: Do not check address of well-known strings We are going to check the address using probe_kernel_address(). It will be more expensive and it does not make sense for well known address. This patch splits the string() function. The variant without the check is then used on locations that handle string constants or strings defined as local variables. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-4-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-04-17 19:53:43 +08:00
buf = string_nocheck(buf, end, "\"", str_spec);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
has_mult = true;
}
break;
default:
break;
}
}
return widen_string(buf, buf - buf_start, end, spec);
}
lib/vsprintf: Add %pfw conversion specifier for printing fwnode names Add support for %pfw conversion specifier (with "f" and "P" modifiers) to support printing full path of the node, including its name ("f") and only the node's name ("P") in the printk family of functions. The two flags have equivalent functionality to existing %pOF with the same two modifiers ("f" and "P") on OF based systems. The ability to do the same on ACPI based systems is added by this patch. On ACPI based systems the resulting strings look like \_SB.PCI0.CIO2.port@1.endpoint@0 where the nodes are separated by a dot (".") and the first three are ACPI device nodes and the latter two ACPI data nodes. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:18 +08:00
static noinline_for_stack
char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode,
struct printf_spec spec, const char *fmt)
vsprintf: Factor out %pO handler as kobject_string() Move code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-7-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:46 +08:00
{
lib/vsprintf: Add %pfw conversion specifier for printing fwnode names Add support for %pfw conversion specifier (with "f" and "P" modifiers) to support printing full path of the node, including its name ("f") and only the node's name ("P") in the printk family of functions. The two flags have equivalent functionality to existing %pOF with the same two modifiers ("f" and "P") on OF based systems. The ability to do the same on ACPI based systems is added by this patch. On ACPI based systems the resulting strings look like \_SB.PCI0.CIO2.port@1.endpoint@0 where the nodes are separated by a dot (".") and the first three are ACPI device nodes and the latter two ACPI data nodes. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:18 +08:00
struct printf_spec str_spec = spec;
char *buf_start = buf;
str_spec.field_width = -1;
if (*fmt != 'w')
return error_string(buf, end, "(%pf?)", spec);
if (check_pointer(&buf, end, fwnode, spec))
return buf;
fmt++;
switch (*fmt) {
case 'P': /* name */
buf = string(buf, end, fwnode_get_name(fwnode), str_spec);
break;
case 'f': /* full_name */
default:
buf = fwnode_full_name_string(fwnode, buf, end);
break;
vsprintf: Factor out %pO handler as kobject_string() Move code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-7-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:46 +08:00
}
lib/vsprintf: Add %pfw conversion specifier for printing fwnode names Add support for %pfw conversion specifier (with "f" and "P" modifiers) to support printing full path of the node, including its name ("f") and only the node's name ("P") in the printk family of functions. The two flags have equivalent functionality to existing %pOF with the same two modifiers ("f" and "P") on OF based systems. The ability to do the same on ACPI based systems is added by this patch. On ACPI based systems the resulting strings look like \_SB.PCI0.CIO2.port@1.endpoint@0 where the nodes are separated by a dot (".") and the first three are ACPI device nodes and the latter two ACPI data nodes. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:18 +08:00
return widen_string(buf, buf - buf_start, end, spec);
vsprintf: Factor out %pO handler as kobject_string() Move code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-7-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:46 +08:00
}
vsprintf: add infrastructure support for extended '%p' specifiers This expands the kernel '%p' handling with an arbitrary alphanumberic specifier extension string immediately following the '%p'. Right now it's just being ignored, but the next commit will start adding some specific pointer type extensions. NOTE! The reason the extension is appended to the '%p' is to allow minimal gcc type checking: gcc will still see the '%p' and will check that the argument passed in is indeed a pointer, and yet will not complain about the extended information that gcc doesn't understand about (on the other hand, it also won't actually check that the pointer type and the extension are compatible). Alphanumeric characters were chosen because there is no sane existing use for a string format with a hex pointer representation immediately followed by alphanumerics (which is what such a format string would have traditionally resulted in). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:24:57 +08:00
/*
* Show a '%p' thing. A kernel extension is that the '%p' is followed
* by an extra set of alphanumeric characters that are extended format
* specifiers.
*
checkpatch: add ability to find bad uses of vsprintf %p<foo> extensions %pK was at least once misused at %pk in an out-of-tree module. This lead to some security concerns. Add the ability to track single and multiple line statements for misuses of %p<foo>. [akpm@linux-foundation.org: add helpful comment into lib/vsprintf.c] [akpm@linux-foundation.org: text tweak] Link: http://lkml.kernel.org/r/163a690510e636a23187c0dc9caa09ddac6d4cde.1488228427.git.joe@perches.com Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: William Roberts <william.c.roberts@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-09 06:55:36 +08:00
* Please update scripts/checkpatch.pl when adding/removing conversion
* characters. (Search for "check for vsprintf extension").
*
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
* Right now we handle:
*
vsprintf: Tweak pF/pf comment Reflect changes that have happened to pf/pF (deprecation) specifiers in pointer() comment section. Link: http://lkml.kernel.org/r/20180414030005.25831-1-sergey.senozhatsky@gmail.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Joe Perches <joe@perches.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-04-14 11:00:05 +08:00
* - 'S' For symbolic direct pointers (or function descriptors) with offset
* - 's' For symbolic direct pointers (or function descriptors) without offset
lib/vsprintf: Remove support for %pF and %pf in favour of %pS and %ps %pS and %ps are now the preferred conversion specifiers to print function names. The functionality is equivalent; remove the old, deprecated %pF and %pf support. Depends-on: commit 2d44d165e939 ("scsi: lpfc: Convert existing %pf users to %ps") Depends-on: commit b295c3e39c13 ("tools lib traceevent: Convert remaining %p[fF] users to %p[sS]") Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:14 +08:00
* - '[Ss]R' as above with __builtin_extract_return_addr() translation
lib/vsprintf: Add a note on re-using %pf or %pF Add a note warning of re-use of obsolete %pf or %pF extensions. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:15 +08:00
* - '[Ff]' %pf and %pF were obsoleted and later removed in favor of
* %ps and %pS. Be careful when re-using these specifiers.
vsprintf: Introduce %pB format specifier The %pB format specifier is for stack backtrace. Its handler sprint_backtrace() does symbol lookup using (address-1) to ensure the address will not point outside of the function. If there is a tail-call to the function marked "noreturn", gcc optimized out the code after the call then causes saved return address points outside of the function (i.e. the start of the next function), so pollutes call trace somewhat. This patch adds the %pB printk mechanism that allows architecture call-trace printout functions to improve backtrace printouts. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arch@vger.kernel.org LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-24 10:42:29 +08:00
* - 'B' For backtraced symbolic direct pointers with offset
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
* - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
* - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
* - 'b[l]' For a bitmap, the number of bits is determined by the field
* width which must be explicitly specified either as part of the
* format string '%32b[l]' or through '%*b[l]', [l] selects
* range-list format instead of hex format
printk: add %pM format specifier for MAC addresses Add format specifiers for printing out six colon-separated bytes: MAC addresses (%pM): xx:xx:xx:xx:xx:xx %#pM is also supported and omits the colon separators. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28 06:47:12 +08:00
* - 'M' For a 6-byte MAC address, it prints the address in the
* usual colon-separated hex notation
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
* - 'm' For a 6-byte MAC address, it prints the hex address without colons
lib/vsprintf.c: Add %pMF to format FDDI bit reversed MAC addresses On Mon, 2010-01-04 at 23:43 +0000, Maciej W. Rozycki wrote: > The example below shows an address, and the sequence of bits or symbols > that would be transmitted when the address is used in the Source Address > or Destination Address fields on the MAC header. The transmission line > shows the address bits in the order transmitted, from left to right. For > IEEE 802 LANs these correspond to actual bits on the medium. The FDDI > symbols line shows how the FDDI PHY sends the address bits as encoded > symbols. > > MSB: 35:7B:12:00:00:01 > Canonical: AC-DE-48-00-00-80 > Transmission: 00110101 01111011 00010010 00000000 00000000 00000001 > FDDI Symbols: 35 7B 12 00 00 01" > > Please note that this address has its group bit clear. > > This notation is also defined in the "FDDI MEDIA ACCESS CONTROL-2 > (MAC-2)" (X3T9/92-120) document although that book does not have a need > to use the MSB form and it's skipped. Adds 6 bytes to object size for x86 New: $ size lib/vsprintf.o text data bss dec hex filename 8664 0 2 8666 21da lib/vsprintf.o $ size lib/vsprintf.o text data bss dec hex filename 8658 0 2 8660 21d4 lib/vsprintf.o Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-07 19:43:50 +08:00
* - 'MF' For a 6-byte MAC FDDI address, it prints the address
lib: Kill bit-reversed FDDI MAC output case, it's bogus. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-11 16:44:14 +08:00
* with a dash-separated hex notation
lib/vsprintf: update documentation to cover all of %p[Mm][FR] Acked-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:12:33 +08:00
* - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
* - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
* IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
* IPv6 uses colon separated network-order 16 bit hex with leading 0's
lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier In order to avoid making code that deals with printing both, IPv4 and IPv6 addresses, unnecessary complicated as for example ... if (sa.sa_family == AF_INET6) printk("... %pI6 ...", ..sin6_addr); else printk("... %pI4 ...", ..sin_addr.s_addr); ... it would be better to introduce a format specifier that can deal with those kind of situations internally; just as we have a "struct sockaddr" for generic mapping into "struct sockaddr_in" or "struct sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could reduce the above statement into something like: printk("... %pIS ..", &sockaddr); In case our pointer is NULL, pointer() then deals with that already at an earlier point in time internally. While we're at it, support for both %piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free. Additionally to that, postfix specifiers 'p', 'f' and 's' are supported as suggested and initially implemented in 2009 by Joe Perches [1]. Handling of those additional specifiers orientate on the initial RFC that was proposed. Also we support IPv6 compressed format specified by 'c' and various other IPv4 extensions as stated in the documentation part. Likely, there are many other areas than just SCTP in the kernel to make use of this extension as well. [1] http://patchwork.ozlabs.org/patch/31480/ Signed-off-by: Daniel Borkmann <dborkman@redhat.com> CC: Joe Perches <joe@perches.com> CC: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-29 01:49:39 +08:00
* [S][pfs]
* Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
* [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
* - 'i' [46] for 'raw' IPv4/IPv6 addresses
* IPv6 omits the colons (01020304...0f)
* IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier In order to avoid making code that deals with printing both, IPv4 and IPv6 addresses, unnecessary complicated as for example ... if (sa.sa_family == AF_INET6) printk("... %pI6 ...", ..sin6_addr); else printk("... %pI4 ...", ..sin_addr.s_addr); ... it would be better to introduce a format specifier that can deal with those kind of situations internally; just as we have a "struct sockaddr" for generic mapping into "struct sockaddr_in" or "struct sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could reduce the above statement into something like: printk("... %pIS ..", &sockaddr); In case our pointer is NULL, pointer() then deals with that already at an earlier point in time internally. While we're at it, support for both %piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free. Additionally to that, postfix specifiers 'p', 'f' and 's' are supported as suggested and initially implemented in 2009 by Joe Perches [1]. Handling of those additional specifiers orientate on the initial RFC that was proposed. Also we support IPv6 compressed format specified by 'c' and various other IPv4 extensions as stated in the documentation part. Likely, there are many other areas than just SCTP in the kernel to make use of this extension as well. [1] http://patchwork.ozlabs.org/patch/31480/ Signed-off-by: Daniel Borkmann <dborkman@redhat.com> CC: Joe Perches <joe@perches.com> CC: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-29 01:49:39 +08:00
* [S][pfs]
* Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
* [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
* - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
* - 'I[6S]c' for IPv6 addresses printed as specified by
vsprintf: Update %pI6c to not compress a single 0 RFC 5952 (http://tools.ietf.org/html/rfc5952) mandates that 2 or more consecutive 0's are required before using :: compression. Update ip6_compressed_string to match the RFC and update the http reference as well. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-10 02:23:37 +08:00
* http://tools.ietf.org/html/rfc5952
lib/vsprintf: add %*pE[achnops] format specifier This allows user to print a given buffer as an escaped string. The rules are applied according to an optional mix of flags provided by additional format letters. For example, if the given buffer is: 1b 62 20 5c 43 07 22 90 0d 5d The result strings would be: %*pE "\eb \C\a"\220\r]" %*pEhp "\x1bb \C\x07"\x90\x0d]" %*pEa "\e\142\040\\\103\a\042\220\r\135" Please, read Documentation/printk-formats.txt and lib/string_helpers.c kernel documentation to get further information. [akpm@linux-foundation.org: tidy up comment layout, per Joe] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Joe Perches <joe@perches.com> Cc: "John W . Linville" <linville@tuxdriver.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 06:55:18 +08:00
* - 'E[achnops]' For an escaped buffer, where rules are defined by combination
* of the following flags (see string_escape_mem() for the
* details):
* a - ESCAPE_ANY
* c - ESCAPE_SPECIAL
* h - ESCAPE_HEX
* n - ESCAPE_NULL
* o - ESCAPE_OCTAL
* p - ESCAPE_NP
* s - ESCAPE_SPACE
* By default ESCAPE_ANY_NP is used.
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
* - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
* "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
* Options for %pU are:
* b big endian lower case hex (default)
* B big endian UPPER case hex
* l little endian lower case hex
* L little endian UPPER case hex
* big endian output byte order is:
* [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
* little endian output byte order is:
* [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
vsprintf: Recursive vsnprintf: Add "%pV", struct va_format Add the ability to print a format and va_list from a structure pointer Allows __dev_printk to be implemented as a single printk while minimizing string space duplication. %pV should not be used without some mechanism to verify the format and argument use ala __attribute__(format (printf(...))). Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-27 09:02:33 +08:00
* - 'V' For a struct va_format which contains a format string * and va_list *,
* call vsnprintf(->format, *->va_list).
* Implements a "recursive vsnprintf".
* Do not use this feature without some mechanism to verify the
* correctness of the format string and va_list arguments.
kptr_restrict for hiding kernel pointers from unprivileged users Add the %pK printk format specifier and the /proc/sys/kernel/kptr_restrict sysctl. The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". [akpm@linux-foundation.org: check for IRQ context when !kptr_restrict, save an indent level, s/WARN/WARN_ONCE/] [akpm@linux-foundation.org: coding-style fixup] [randy.dunlap@oracle.com: fix kernel/sysctl.c warning] Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:59:41 +08:00
* - 'K' For a kernel pointer that should be hidden from unprivileged users
net: introduce and use netdev_features_t for device features sets v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-15 23:29:55 +08:00
* - 'NF' For a netdev_features_t
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
* - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
* a certain separator (' ' by default):
* C colon
* D dash
* N no separator
* The maximum supported length is 64 bytes of the input. Consider
* to use print_hex_dump() for the larger input.
vsprintf: add %pad extension for dma_addr_t use dma_addr_t's can be either u32 or u64 depending on a CONFIG option. There are a few hundred dma_addr_t's printed via either cast to unsigned long long, unsigned long or no cast at all. Add %pad to be able to emit them without the cast. Update Documentation/printk-formats.txt too. Signed-off-by: Joe Perches <joe@perches.com> Cc: "Shevchenko, Andriy" <andriy.shevchenko@intel.com> Cc: Rob Landley <rob@landley.net> Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-24 07:54:17 +08:00
* - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
* (default assumed to be phys_addr_t, passed by reference)
lib/vsprintf.c: document formats for dentry and struct file Looks like these were added to Documentation/printk-formats.txt but not the in-file table. Signed-off-by: Olof Johansson <olof@lixom.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 07:09:50 +08:00
* - 'd[234]' For a dentry name (optionally 2-4 last components)
* - 'D[234]' Same as 'd' but for a struct file
lib/vsprintf: add %*pg format specifier This allow to directly print block_device name. Currently one should use bdevname() with temporal char buffer. This is very ineffective because bloat stack usage for deep IO call-traces Example: %pg -> sda, sda1 or loop0p1 [AV: fixed a minor braino - position updates should not be dependent upon having reached the of buffer] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-13 20:31:35 +08:00
* - 'g' For block_device name (gendisk + partition number)
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
* - 't[R][dt][r]' For time and date as represented:
* R struct rtc_time
lib/vsprintf: add %pC{,n,r} format specifiers for clocks Add format specifiers for printing struct clk: - '%pC' or '%pCn': name (Common Clock Framework) or address (legacy clock framework) of the clock, - '%pCr': rate of the clock. [akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:20 +08:00
* - 'C' For a clock, it prints the name (Common Clock Framework) or address
* (legacy clock framework) of the clock
* - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
* (legacy clock framework) of the clock
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
* - 'G' For flags to be printed as a collection of symbolic strings that would
* construct the specific value. Supported flags given by option:
* p page flags (see struct page) given as pointer to unsigned long
* g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
* v vma flags (VM_*) given as pointer to unsigned long
doc: printk-formats: Remove bogus kobject references for device nodes When converting from text to rst, the kobjects section and its sole subsection about device tree nodes were coalesced into a single section, yielding an inconsistent result. Remove all references to kobjects, as 1. Device tree object pointers are not compatible to kobject pointers (the former may embed the latter, though), and 2. there are no printk formats defined for kobject types. Update the vsprintf() source code comments to match the above. Fixes: b3ed23213eab1e08 ("doc: convert printk-formats.txt to rst") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-08 19:08:48 +08:00
* - 'OF[fnpPcCF]' For a device tree object
* Without any optional arguments prints the full_name
* f device node full_name
* n device node name
* p device node phandle
* P device node path spec (name + @unit)
* F device node flags
* c major compatible string
* C full compatible string
lib/vsprintf: Add %pfw conversion specifier for printing fwnode names Add support for %pfw conversion specifier (with "f" and "P" modifiers) to support printing full path of the node, including its name ("f") and only the node's name ("P") in the printk family of functions. The two flags have equivalent functionality to existing %pOF with the same two modifiers ("f" and "P") on OF based systems. The ability to do the same on ACPI based systems is added by this patch. On ACPI based systems the resulting strings look like \_SB.PCI0.CIO2.port@1.endpoint@0 where the nodes are separated by a dot (".") and the first three are ACPI device nodes and the latter two ACPI data nodes. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:18 +08:00
* - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer
* Without an option prints the full name of the node
* f full name
* P node name, including a possible unit address
vsprintf: add printk specifier %px printk specifier %p now hashes all addresses before printing. Sometimes we need to see the actual unmodified address. This can be achieved using %lx but then we face the risk that if in future we want to change the way the Kernel handles printing of pointers we will have to grep through the already existent 50 000 %lx call sites. Let's add specifier %px as a clear, opt-in, way to print a pointer and maintain some level of isolation from all the other hex integer output within the Kernel. Add printk specifier %px to print the actual unmodified address. Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-23 07:59:45 +08:00
* - 'x' For printing the address. Equivalent to "%lx".
bpf: Restrict bpf_trace_printk()'s %s usage and add %pks, %pus specifier Usage of plain %s conversion specifier in bpf_trace_printk() suffers from the very same issue as bpf_probe_read{,str}() helpers, that is, it is broken on archs with overlapping address ranges. While the helpers have been addressed through work in 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers"), we need an option for bpf_trace_printk() as well to fix it. Similarly as with the helpers, force users to make an explicit choice by adding %pks and %pus specifier to bpf_trace_printk() which will then pick the corresponding strncpy_from_unsafe*() variant to perform the access under KERNEL_DS or USER_DS. The %pk* (kernel specifier) and %pu* (user specifier) can later also be extended for other objects aside strings that are probed and printed under tracing, and reused out of other facilities like bpf_seq_printf() or BTF based type printing. Existing behavior of %s for current users is still kept working for archs where it is not broken and therefore gated through CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE. For archs not having this property we fall-back to pick probing under KERNEL_DS as a sensible default. Fixes: 8d3b7dce8622 ("bpf: add support for %s specifier to bpf_trace_printk()") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Link: https://lore.kernel.org/bpf/20200515101118.6508-4-daniel@iogearbox.net
2020-05-15 18:11:18 +08:00
* - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of
* bpf_trace_printk() where [ku] prefix specifies either kernel (k)
* or user (u) memory to probe, and:
* s a string, equivalent to "%s" on direct vsnprintf() use
vsprintf: add printk specifier %px printk specifier %p now hashes all addresses before printing. Sometimes we need to see the actual unmodified address. This can be achieved using %lx but then we face the risk that if in future we want to change the way the Kernel handles printing of pointers we will have to grep through the already existent 50 000 %lx call sites. Let's add specifier %px as a clear, opt-in, way to print a pointer and maintain some level of isolation from all the other hex integer output within the Kernel. Add printk specifier %px to print the actual unmodified address. Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-23 07:59:45 +08:00
*
doc: convert printk-formats.txt to rst Documentation/printk-formats.txt is a candidate for conversion to ReStructuredText format. Some effort has already been made to do this conversion even thought the suffix is currently .txt Changes required to complete conversion - Move printk-formats.txt to core-api/printk-formats.rst - Add entry to Documentation/core-api/index.rst - Remove entry from Documentation/00-INDEX - Fix minor grammatical errors. - Order heading adornments as suggested by rst docs. - Use 'Passed by reference' uniformly. - Update pointer documentation around %px specifier. - Fix erroneous double backticks (to commas). - Remove extraneous double backticks (suggested by Jonathan Corbet). - Simplify documentation for kobject. Signed-off-by: Tobin C. Harding <me@tobin.cc> [jc: downcased "kernel"] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-20 05:17:15 +08:00
* ** When making changes please also update:
* Documentation/core-api/printk-formats.rst
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
*
printk: hash addresses printed with %p Currently there exist approximately 14 000 places in the kernel where addresses are being printed using an unadorned %p. This potentially leaks sensitive information regarding the Kernel layout in memory. Many of these calls are stale, instead of fixing every call lets hash the address by default before printing. This will of course break some users, forcing code printing needed addresses to be updated. Code that _really_ needs the address will soon be able to use the new printk specifier %px to print the address. For what it's worth, usage of unadorned %p can be broken down as follows (thanks to Joe Perches). $ git grep -E '%p[^A-Za-z0-9]' | cut -f1 -d"/" | sort | uniq -c 1084 arch 20 block 10 crypto 32 Documentation 8121 drivers 1221 fs 143 include 101 kernel 69 lib 100 mm 1510 net 40 samples 7 scripts 11 security 166 sound 152 tools 2 virt Add function ptr_to_id() to map an address to a 32 bit unique identifier. Hash any unadorned usage of specifier %p and any malformed specifiers. Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-01 12:32:23 +08:00
* Note: The default behaviour (unadorned %p) is to hash the address,
* rendering it useful as a unique identifier.
vsprintf: add infrastructure support for extended '%p' specifiers This expands the kernel '%p' handling with an arbitrary alphanumberic specifier extension string immediately following the '%p'. Right now it's just being ignored, but the next commit will start adding some specific pointer type extensions. NOTE! The reason the extension is appended to the '%p' is to allow minimal gcc type checking: gcc will still see the '%p' and will check that the argument passed in is indeed a pointer, and yet will not complain about the extended information that gcc doesn't understand about (on the other hand, it also won't actually check that the pointer type and the extension are compatible). Alphanumeric characters were chosen because there is no sane existing use for a string format with a hex pointer representation immediately followed by alphanumerics (which is what such a format string would have traditionally resulted in). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:24:57 +08:00
*/
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
char *pointer(const char *fmt, char *buf, char *end, void *ptr,
struct printf_spec spec)
vsprintf: split out '%p' handling logic The actual code is the same, just split out into a helper function. This makes it easier to read, and allows for simple future extension of %p handling. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:16:15 +08:00
{
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
switch (*fmt) {
case 'S':
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
case 's':
symbol lookup: introduce dereference_symbol_descriptor() dereference_symbol_descriptor() invokes appropriate ARCH specific function descriptor dereference callbacks: - dereference_kernel_function_descriptor() if the pointer is a kernel symbol; - dereference_module_function_descriptor() if the pointer is a module symbol. This is the last step needed to make '%pS/%ps' smart enough to handle function descriptor dereference on affected ARCHs and to retire '%pF/%pf'. To refresh it: Some architectures (ia64, ppc64, parisc64) use an indirect pointer for C function pointers - the function pointer points to a function descriptor and we need to dereference it to get the actual function pointer. Function descriptors live in .opd elf section and all affected ARCHs (ia64, ppc64, parisc64) handle it properly for kernel and modules. So we, technically, can decide if the dereference is needed by simply looking at the pointer: if it belongs to .opd section then we need to dereference it. The kernel and modules have their own .opd sections, obviously, that's why we need to split dereference_function_descriptor() and use separate kernel and module dereference arch callbacks. Link: http://lkml.kernel.org/r/20171206043649.GB15885@jagdpanzerIV Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: James Bottomley <jejb@parisc-linux.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-ia64@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Tony Luck <tony.luck@intel.com> #ia64 Tested-by: Santosh Sivaraj <santosh@fossix.org> #powerpc Tested-by: Helge Deller <deller@gmx.de> #parisc64 Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-12-06 12:36:49 +08:00
ptr = dereference_symbol_descriptor(ptr);
/* Fallthrough */
vsprintf: Introduce %pB format specifier The %pB format specifier is for stack backtrace. Its handler sprint_backtrace() does symbol lookup using (address-1) to ensure the address will not point outside of the function. If there is a tail-call to the function marked "noreturn", gcc optimized out the code after the call then causes saved return address points outside of the function (i.e. the start of the next function), so pollutes call trace somewhat. This patch adds the %pB printk mechanism that allows architecture call-trace printout functions to improve backtrace printouts. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arch@vger.kernel.org LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-24 10:42:29 +08:00
case 'B':
vsprintf: Add extension %pSR - print_symbol replacement print_symbol takes a long and converts it to a function name and offset. %pS does something similar, but doesn't translate the address via __builtin_extract_return_addr. %pSR does the translation. This will enable replacing multiple calls like printk(...); printk_symbol(addr); printk("\n"); with a single non-interleavable in dmesg printk("... %pSR\n", (void *)addr); Update documentation too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-13 02:18:50 +08:00
return symbol_string(buf, end, ptr, spec, fmt);
Implement %pR to print struct resource content Add a %pR option to the kernel vsnprintf that prints the range of addresses inside a struct resource passed by pointer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 12:07:34 +08:00
case 'R':
vsprintf: use %pR, %pr instead of %pRt, %pRf Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This is the diff between v1 and v2. The changes in this patch are: - tidied vsprintf stack buffer to shrink and compute size more accurately - use %pR for decoding and %pr for "raw" (with type and flags) instead of adding %pRt and %pRf [1] http://lkml.org/lkml/2009/10/6/491 [2] http://lkml.org/lkml/2009/10/13/441 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-28 03:26:47 +08:00
case 'r':
vsprintf: add %pRt, %pRf to print struct resource details This adds support for printing struct resource type and flag information. For example, "%pRt" looks like "[mem 0x80080000000-0x8008001ffff 64bit pref]", and "%pRf" looks like "[mem 0xff5e2000-0xff5e2007 pref flags 0x1]". Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 05:33:39 +08:00
return resource_string(buf, end, ptr, spec, fmt);
vsprintf: add support of '%*ph[CDN]' There are many places in the kernel where the drivers print small buffers as a hex string. This patch adds a support of the variable width buffer to print it as a hex string with a delimiter. The idea came from Pavel Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/ Sample output of pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]); could be look like this: [ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e [ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55 [ 0.757602] buf[17:5] ac:16:d5:2c:ef Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:27 +08:00
case 'h':
return hex_string(buf, end, ptr, spec, fmt);
lib/vsprintf: implement bitmap printing through '%*pb[l]' bitmap and its derivatives such as cpumask and nodemask currently only provide formatting functions which put the output string into the provided buffer; however, how long this buffer should be isn't defined anywhere and given that some of these bitmaps can be too large to be formatted into an on-stack buffer it users sometimes are unnecessarily forced to come up with creative solutions and compromises for the buffer just to printk these bitmaps. There have been a couple different attempts at making this easier. 1. Way back, PeterZ tried printk '%pb' extension with the precision for bit width - '%.*pb'. This was intuitive and made sense but unfortunately triggered a compile warning about using precision for a pointer. http://lkml.kernel.org/g/1336577562.2527.58.camel@twins 2. I implemented bitmap_pr_cont[_list]() and its wrappers for cpumask and nodemask. This works but PeterZ pointed out that pr_cont's tendency to produce broken lines when multiple CPUs are printing is bothering considering the usages. http://lkml.kernel.org/g/1418226774-30215-3-git-send-email-tj@kernel.org So, this patch is another attempt at teaching printk and friends how to print bitmaps. It's almost identical to what PeterZ tried with precision but it uses the field width for the number of bits instead of precision. The format used is '%*pb[l]', with the optional trailing 'l' specifying list format instead of hex masks. This is a valid format string and doesn't trigger compiler warnings; however, it does make it impossible to specify output field width when printing bitmaps. I think this is an acceptable trade-off given how much easier it makes printing bitmaps and that we don't have any in-kernel user which is using the field width specification. If any future user wants to use field width with a bitmap, it'd have to format the bitmap into a string buffer and then print that buffer with width spec, which isn't different from how it should be done now. This patch implements bitmap[_list]_string() which are called from the vsprintf pointer() formatting function. The implementation is mostly identical to bitmap_scn[list]printf() except that the output is performed in the vsprintf way. These functions handle formatting into too small buffers and sprintf() family of functions report the correct overrun output length. bitmap_scn[list]printf() are now thin wrappers around scnprintf(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: "John W. Linville" <linville@tuxdriver.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mike Travis <travis@sgi.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-14 06:36:53 +08:00
case 'b':
switch (fmt[1]) {
case 'l':
return bitmap_list_string(buf, end, ptr, spec, fmt);
default:
return bitmap_string(buf, end, ptr, spec, fmt);
}
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
case 'M': /* Colon separated: 00:01:02:03:04:05 */
case 'm': /* Contiguous: 000102030405 */
vsprintf: add %pMR for Bluetooth MAC address Bluetooth uses mostly LE byte order which is reversed for visual interpretation. Currently in Bluetooth in use unsafe batostr function. This is a slightly modified version of Joe's patch (sent Sat, Dec 4, 2010). Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Joe Perches <joe@perches.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:23 +08:00
/* [mM]F (FDDI) */
/* [mM]R (Reverse order; Bluetooth) */
lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address Signed-off-by: Joe Perches <joe@perches.com> Tested-by: Jens Rosenboom <jens@mcbone.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 20:29:44 +08:00
return mac_address_string(buf, end, ptr, spec, fmt);
case 'I': /* Formatted IP supported
* 4: 1.2.3.4
* 6: 0001:0203:...:0708
* 6c: 1::708 or 1::1.2.3.4
*/
case 'i': /* Contiguous:
* 4: 001.002.003.004
* 6: 000102...0f
*/
vsprintf: Factor out %p[iI] handler as ip_addr_string() Move the non-trivial code from the long pointer() function. We are going to improve error handling that will make it even more complicated. This patch does not change the existing behavior. Link: http://lkml.kernel.org/r/20190417115350.20479-5-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:44 +08:00
return ip_addr_string(buf, end, ptr, spec, fmt);
lib/vsprintf: add %*pE[achnops] format specifier This allows user to print a given buffer as an escaped string. The rules are applied according to an optional mix of flags provided by additional format letters. For example, if the given buffer is: 1b 62 20 5c 43 07 22 90 0d 5d The result strings would be: %*pE "\eb \C\a"\220\r]" %*pEhp "\x1bb \C\x07"\x90\x0d]" %*pEa "\e\142\040\\\103\a\042\220\r\135" Please, read Documentation/printk-formats.txt and lib/string_helpers.c kernel documentation to get further information. [akpm@linux-foundation.org: tidy up comment layout, per Joe] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Joe Perches <joe@perches.com> Cc: "John W . Linville" <linville@tuxdriver.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 06:55:18 +08:00
case 'E':
return escaped_string(buf, end, ptr, spec, fmt);
lib/vsprintf.c: add %pU to print UUID/GUIDs UUID/GUIDs are somewhat common in kernel source. Standardize the printed style of UUID/GUIDs by using another extension to %p. %pUb: 01020304-0506-0708-090a-0b0c0d0e0f10 %pUB: 01020304-0506-0708-090A-0B0C0D0E0F10 (upper case) %pUl: 04030201-0605-0807-090a-0b0c0d0e0f10 %pUL: 04030201-0605-0807-090A-0B0C0D0E0F10 (upper case) %pU defaults to %pUb Signed-off-by: Joe Perches <joe@perches.com> Cc: Jeff Garzik <jgarzik@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alex Elder <aelder@sgi.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Adrian Hunter <adrian.hunter@nokia.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:09 +08:00
case 'U':
return uuid_string(buf, end, ptr, spec, fmt);
vsprintf: Recursive vsnprintf: Add "%pV", struct va_format Add the ability to print a format and va_list from a structure pointer Allows __dev_printk to be implemented as a single printk while minimizing string space duplication. %pV should not be used without some mechanism to verify the format and argument use ala __attribute__(format (printf(...))). Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-27 09:02:33 +08:00
case 'V':
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
return va_format(buf, end, ptr, spec, fmt);
kptr_restrict for hiding kernel pointers from unprivileged users Add the %pK printk format specifier and the /proc/sys/kernel/kptr_restrict sysctl. The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". [akpm@linux-foundation.org: check for IRQ context when !kptr_restrict, save an indent level, s/WARN/WARN_ONCE/] [akpm@linux-foundation.org: coding-style fixup] [randy.dunlap@oracle.com: fix kernel/sysctl.c warning] Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:59:41 +08:00
case 'K':
vsprintf: refactor %pK code out of pointer() Currently code to handle %pK is all within the switch statement in pointer(). This is the wrong level of abstraction. Each of the other switch clauses call a helper function, pK should do the same. Refactor code out of pointer() to new function restricted_pointer(). Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-23 07:56:39 +08:00
return restricted_pointer(buf, end, ptr, spec);
net: introduce and use netdev_features_t for device features sets v2: add couple missing conversions in drivers split unexporting netdev_fix_features() implemented %pNF convert sock::sk_route_(no?)caps Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-15 23:29:55 +08:00
case 'N':
lib/vsprintf: Hash printed address for netdev bits fallback The handler for "%pN" falls back to printing the raw pointer value when using a different format than the (sole supported) special format "%pNF", potentially leaking sensitive information regarding the kernel layout in memory. Avoid this leak by printing the hashed address instead. Note that there are no in-tree users of the fallback. Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p") Link: http://lkml.kernel.org/r/20181011084249.4520-4-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11 16:42:49 +08:00
return netdev_bits(buf, end, ptr, spec, fmt);
lib/vsprintf.c: add %pa format specifier for phys_addr_t types Add the %pa format specifier for printing a phys_addr_t type and its derivative types (such as resource_size_t), since the physical address size on some platforms can vary based on build options, regardless of the native integer type. Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org> Cc: Rob Landley <rob@landley.net> Cc: George Spelvin <linux@horizon.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Andrei Emeltchenko <andrei.emeltchenko@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-22 08:43:09 +08:00
case 'a':
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
return address_val(buf, end, ptr, spec, fmt);
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
case 'd':
return dentry_name(buf, end, ptr, spec, fmt);
lib/vsprintf: Print time and date in human readable format via %pt There are users which print time and date represented by content of struct rtc_time in human readable format. Instead of open coding that each time introduce %ptR[dt][r] specifier. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-05 05:23:11 +08:00
case 't':
return time_and_date(buf, end, ptr, spec, fmt);
lib/vsprintf: add %pC{,n,r} format specifiers for clocks Add format specifiers for printing struct clk: - '%pC' or '%pCn': name (Common Clock Framework) or address (legacy clock framework) of the clock, - '%pCr': rate of the clock. [akpm@linux-foundation.org: omit code if !CONFIG_HAVE_CLK] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:20 +08:00
case 'C':
return clock(buf, end, ptr, spec, fmt);
add formats for dentry/file pathnames New formats: %p[dD][234]?. The next pointer is interpreted as struct dentry * or struct file * resp. ('d' => dentry, 'D' => file) and the last component(s) of pathname are printed (%pd => just the last one, %pd2 => the last two, etc.) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-04 00:00:44 +08:00
case 'D':
vsprintf: Prevent crash when dereferencing invalid pointers for %pD Commit 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") prevents most crash except for %pD. There is an additional pointer dereferencing before dentry_name. At least, vma->file can be NULL and be passed to printk %pD in print_bad_pte, which can cause crash. This patch fixes it with introducing a new file_dentry_name. Link: http://lkml.kernel.org/r/20190809012457.56685-1-justin.he@arm.com Fixes: 3e5903eb9cff ("vsprintf: Prevent crash when dereferencing invalid pointers") To: Geert Uytterhoeven <geert+renesas@glider.be> To: Thomas Gleixner <tglx@linutronix.de> To: Andy Shevchenko <andriy.shevchenko@linux.intel.com> To: linux-kernel@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Shuah Khan <shuah@kernel.org> Cc: "Tobin C. Harding" <tobin@kernel.org> Signed-off-by: Jia He <justin.he@arm.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-08-09 09:24:56 +08:00
return file_dentry_name(buf, end, ptr, spec, fmt);
lib/vsprintf: add %*pg format specifier This allow to directly print block_device name. Currently one should use bdevname() with temporal char buffer. This is very ineffective because bloat stack usage for deep IO call-traces Example: %pg -> sda, sda1 or loop0p1 [AV: fixed a minor braino - position updates should not be dependent upon having reached the of buffer] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-13 20:31:35 +08:00
#ifdef CONFIG_BLOCK
case 'g':
return bdev_name(buf, end, ptr, spec, fmt);
#endif
mm, printk: introduce new format string for flags In mm we use several kinds of flags bitfields that are sometimes printed for debugging purposes, or exported to userspace via sysfs. To make them easier to interpret independently on kernel version and config, we want to dump also the symbolic flag names. So far this has been done with repeated calls to pr_cont(), which is unreliable on SMP, and not usable for e.g. sysfs export. To get a more reliable and universal solution, this patch extends printk() format string for pointers to handle the page flags (%pGp), gfp_flags (%pGg) and vma flags (%pGv). Existing users of dump_flag_names() are converted and simplified. It would be possible to pass flags by value instead of pointer, but the %p format string for pointers already has extensions for various kernel structures, so it's a good fit, and the extra indirection in a non-critical path is negligible. [linux@rasmusvillemoes.dk: lots of good implementation suggestions] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-16 05:55:56 +08:00
case 'G':
vsprintf: Consolidate handling of unknown pointer specifiers There are few printk formats that make sense only with two or more specifiers. Also some specifiers make sense only when a kernel feature is enabled. The handling of unknown specifiers is inconsistent and not helpful. Using WARN() looks like an overkill for this type of error. pr_warn() is not good either. It would by handled via printk_safe buffer and it might be hard to match it with the problematic string. A reasonable compromise seems to be writing the unknown format specifier into the original string with a question mark, for example (%pC?). It should be self-explaining enough. Note that it is in brackets to follow the (null) style. Note that it introduces a warning about that test_hashed() function is unused. It is going to be used again by a later patch. Link: http://lkml.kernel.org/r/20190417115350.20479-8-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:47 +08:00
return flags_string(buf, end, ptr, spec, fmt);
vsprintf: Add %p extension "%pOF" for device tree 90% of the usage of device node's full_name is printing it out in a kernel message. However, storing the full path for every node is wasteful and redundant. With a custom format specifier, we can generate the full path at run-time and eventually remove the full path from every node. For instance typical use is: pr_info("Frobbing node %s\n", node->full_name); Which can be written now as: pr_info("Frobbing node %pOF\n", node); '%pO' is the base specifier to represent kobjects with '%pOF' representing struct device_node. Currently, struct device_node is the only supported type of kobject. More fine-grained control of formatting includes printing the name, flags, path-spec name and others, explained in the documentation entry. Originally written by Pantelis, but pretty much rewrote the core function using existing string/number functions. The 2 passes were unnecessary and have been removed. Also, updated the checkpatch.pl check. The unittest code was written by Grant Likely. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Rob Herring <robh@kernel.org>
2015-01-22 01:06:14 +08:00
case 'O':
lib/vsprintf: OF nodes are first and foremost, struct device_nodes Factor out static kobject_string() function that simply calls device_node_string(), and thus remove references to kobjects (as these are struct device_node). Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:17 +08:00
return device_node_string(buf, end, ptr, spec, fmt + 1);
lib/vsprintf: Add %pfw conversion specifier for printing fwnode names Add support for %pfw conversion specifier (with "f" and "P" modifiers) to support printing full path of the node, including its name ("f") and only the node's name ("P") in the printk family of functions. The two flags have equivalent functionality to existing %pOF with the same two modifiers ("f" and "P") on OF based systems. The ability to do the same on ACPI based systems is added by this patch. On ACPI based systems the resulting strings look like \_SB.PCI0.CIO2.port@1.endpoint@0 where the nodes are separated by a dot (".") and the first three are ACPI device nodes and the latter two ACPI data nodes. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-03 20:32:18 +08:00
case 'f':
return fwnode_string(buf, end, ptr, spec, fmt + 1);
vsprintf: add printk specifier %px printk specifier %p now hashes all addresses before printing. Sometimes we need to see the actual unmodified address. This can be achieved using %lx but then we face the risk that if in future we want to change the way the Kernel handles printing of pointers we will have to grep through the already existent 50 000 %lx call sites. Let's add specifier %px as a clear, opt-in, way to print a pointer and maintain some level of isolation from all the other hex integer output within the Kernel. Add printk specifier %px to print the actual unmodified address. Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-23 07:59:45 +08:00
case 'x':
return pointer_string(buf, end, ptr, spec);
printf: add support for printing symbolic error names It has been suggested several times to extend vsnprintf() to be able to convert the numeric value of ENOSPC to print "ENOSPC". This implements that as a %p extension: With %pe, one can do if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %pe\n", foo); return PTR_ERR(foo); } instead of what is seen in quite a few places in the kernel: if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %ld\n", PTR_ERR(foo)); return PTR_ERR(foo); } If the value passed to %pe is an ERR_PTR, but the library function errname() added here doesn't know about the value, the value is simply printed in decimal. If the value passed to %pe is not an ERR_PTR, we treat it as an ordinary %p and thus print the hashed value (passing non-ERR_PTR values to %pe indicates a bug in the caller, but we can't do much about that). With my embedded hat on, and because it's not very invasive to do, I've made it possible to remove this. The errname() function and associated lookup tables take up about 3K. For most, that's probably quite acceptable and a price worth paying for more readable dmesg (once this starts getting used), while for those that disable printk() it's of very little use - I don't see a procfs/sysfs/seq_printf() file reasonably making use of this - and they clearly want to squeeze vmlinux as much as possible. Hence the default y if PRINTK. The symbols to include have been found by massaging the output of find arch include -iname 'errno*.h' | xargs grep -E 'define\s*E' In the cases where some common aliasing exists (e.g. EAGAIN=EWOULDBLOCK on all platforms, EDEADLOCK=EDEADLK on most), I've moved the more popular one (in terms of 'git grep -w Efoo | wc) to the bottom so that one takes precedence. Link: http://lkml.kernel.org/r/20191015190706.15989-1-linux@rasmusvillemoes.dk To: "Jonathan Corbet" <corbet@lwn.net> To: linux-kernel@vger.kernel.org Cc: "Andy Shevchenko" <andy.shevchenko@gmail.com> Cc: "Andrew Morton" <akpm@linux-foundation.org> Cc: "Joe Perches" <joe@perches.com> Cc: linux-doc@vger.kernel.org Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Uwe Kleine-König <uwe@kleine-koenig.org> Reviewed-by: Petr Mladek <pmladek@suse.com> [andy.shevchenko@gmail.com: use abs()] Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-16 03:07:05 +08:00
case 'e':
/* %pe with a non-ERR_PTR gets treated as plain %p */
if (!IS_ERR(ptr))
break;
return err_ptr(buf, end, ptr, spec);
bpf: Restrict bpf_trace_printk()'s %s usage and add %pks, %pus specifier Usage of plain %s conversion specifier in bpf_trace_printk() suffers from the very same issue as bpf_probe_read{,str}() helpers, that is, it is broken on archs with overlapping address ranges. While the helpers have been addressed through work in 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers"), we need an option for bpf_trace_printk() as well to fix it. Similarly as with the helpers, force users to make an explicit choice by adding %pks and %pus specifier to bpf_trace_printk() which will then pick the corresponding strncpy_from_unsafe*() variant to perform the access under KERNEL_DS or USER_DS. The %pk* (kernel specifier) and %pu* (user specifier) can later also be extended for other objects aside strings that are probed and printed under tracing, and reused out of other facilities like bpf_seq_printf() or BTF based type printing. Existing behavior of %s for current users is still kept working for archs where it is not broken and therefore gated through CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE. For archs not having this property we fall-back to pick probing under KERNEL_DS as a sensible default. Fixes: 8d3b7dce8622 ("bpf: add support for %s specifier to bpf_trace_printk()") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Link: https://lore.kernel.org/bpf/20200515101118.6508-4-daniel@iogearbox.net
2020-05-15 18:11:18 +08:00
case 'u':
case 'k':
switch (fmt[1]) {
case 's':
return string(buf, end, ptr, spec);
default:
return error_string(buf, end, "(einval)", spec);
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
}
printk: hash addresses printed with %p Currently there exist approximately 14 000 places in the kernel where addresses are being printed using an unadorned %p. This potentially leaks sensitive information regarding the Kernel layout in memory. Many of these calls are stale, instead of fixing every call lets hash the address by default before printing. This will of course break some users, forcing code printing needed addresses to be updated. Code that _really_ needs the address will soon be able to use the new printk specifier %px to print the address. For what it's worth, usage of unadorned %p can be broken down as follows (thanks to Joe Perches). $ git grep -E '%p[^A-Za-z0-9]' | cut -f1 -d"/" | sort | uniq -c 1084 arch 20 block 10 crypto 32 Documentation 8121 drivers 1221 fs 143 include 101 kernel 69 lib 100 mm 1510 net 40 samples 7 scripts 11 security 166 sound 152 tools 2 virt Add function ptr_to_id() to map an address to a 32 bit unique identifier. Hash any unadorned usage of specifier %p and any malformed specifiers. Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-01 12:32:23 +08:00
/* default is to _not_ leak addresses, hash before printing */
return ptr_to_id(buf, end, ptr, spec);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
}
/*
* Helper function to decode printf style format.
* Each call decode a token from the format and return the
* number of characters read (or likely the delta where it wants
* to go on the next call).
* The decoded token is returned through the parameters
*
* 'h', 'l', or 'L' for integer fields
* 'z' support added 23/7/1999 S.H.
* 'z' changed to 'Z' --davidm 1/25/99
lib/vsprintf.c: remove %Z support Now that %z is standartised in C99 there is no reason to support %Z. Unlike %L it doesn't even make format strings smaller. Use BUILD_BUG_ON in a couple ATM drivers. In case anyone didn't notice lib/vsprintf.o is about half of SLUB which is in my opinion is quite an achievement. Hopefully this patch inspires someone else to trim vsprintf.c more. Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-28 06:30:02 +08:00
* 'Z' changed to 'z' --adobriyan 2017-01-25
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
* 't' added for ptrdiff_t
*
* @fmt: the format string
* @type of the token returned
* @flags: various flags such as +, -, # tokens..
* @field_width: overwritten width
* @base: base of the number (octal, hex, ...)
* @precision: precision of a number
* @qualifier: qualifier of a number (long, size_t, ...)
*/
vsprintf.c: use noinline_for_stack Mark static functions with noinline_for_stack Before: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000e82 pointer [vsprintf.o]: 344 0x0000198c pointer [vsprintf.o]: 344 0x000025d6 scnprintf [vsprintf.o]: 216 0x00002648 scnprintf [vsprintf.o]: 216 0x00002565 snprintf [vsprintf.o]: 208 0x0000267c sprintf [vsprintf.o]: 208 0x000030a3 bprintf [vsprintf.o]: 208 0x00003b1e sscanf [vsprintf.o]: 208 0x00000608 number [vsprintf.o]: 136 0x00000937 number [vsprintf.o]: 136 After: akpm:/usr/src/25> objdump -d lib/vsprintf.o | perl scripts/checkstack.pl 0x00000a7c symbol_string [vsprintf.o]: 248 0x00000ae8 symbol_string [vsprintf.o]: 248 0x00002310 scnprintf [vsprintf.o]: 216 0x00002382 scnprintf [vsprintf.o]: 216 0x0000229f snprintf [vsprintf.o]: 208 0x000023b6 sprintf [vsprintf.o]: 208 0x00002ddd bprintf [vsprintf.o]: 208 0x00003858 sscanf [vsprintf.o]: 208 0x00000625 number [vsprintf.o]: 136 0x00000954 number [vsprintf.o]: 136 Signed-off-by: Joe Perches <joe@perches.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:16 +08:00
static noinline_for_stack
int format_decode(const char *fmt, struct printf_spec *spec)
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
{
const char *start = fmt;
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
char qualifier;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
/* we finished early by reading the field width */
vsprintf: unify the format decoding layer for its 3 users, cleanup Impact: cleanup Rename FORMAT_TYPE_WITDH to => FORMAT_TYPE_WIDTH Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
if (spec->type == FORMAT_TYPE_WIDTH) {
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (spec->field_width < 0) {
spec->field_width = -spec->field_width;
spec->flags |= LEFT;
}
spec->type = FORMAT_TYPE_NONE;
goto precision;
}
/* we finished early by reading the precision */
if (spec->type == FORMAT_TYPE_PRECISION) {
if (spec->precision < 0)
spec->precision = 0;
spec->type = FORMAT_TYPE_NONE;
goto qualifier;
}
/* By default */
spec->type = FORMAT_TYPE_NONE;
for (; *fmt ; ++fmt) {
if (*fmt == '%')
break;
}
/* Return the current non-format string */
if (fmt != start || !*fmt)
return fmt - start;
/* Process flags */
spec->flags = 0;
while (1) { /* this also skips first '%' */
bool found = true;
++fmt;
switch (*fmt) {
case '-': spec->flags |= LEFT; break;
case '+': spec->flags |= PLUS; break;
case ' ': spec->flags |= SPACE; break;
case '#': spec->flags |= SPECIAL; break;
case '0': spec->flags |= ZEROPAD; break;
default: found = false;
}
if (!found)
break;
}
/* get field width */
spec->field_width = -1;
if (isdigit(*fmt))
spec->field_width = skip_atoi(&fmt);
else if (*fmt == '*') {
/* it's the next argument */
vsprintf: unify the format decoding layer for its 3 users, cleanup Impact: cleanup Rename FORMAT_TYPE_WITDH to => FORMAT_TYPE_WIDTH Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
spec->type = FORMAT_TYPE_WIDTH;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
return ++fmt - start;
}
precision:
/* get the precision */
spec->precision = -1;
if (*fmt == '.') {
++fmt;
if (isdigit(*fmt)) {
spec->precision = skip_atoi(&fmt);
if (spec->precision < 0)
spec->precision = 0;
} else if (*fmt == '*') {
/* it's the next argument */
fix regression from "vsprintf: unify the format decoding layer for its 3 users" Jeremy Fitzhardinge reported: > Change fef20d9c1380f04ba9492d6463148db07b413708, "vsprintf: > unify the format decoding layer for its 3 users", causes a > regression in xenbus which results in no devices getting > attached to a new domain. %.*s is broken - fix it. Reported-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
spec->type = FORMAT_TYPE_PRECISION;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
return ++fmt - start;
}
}
qualifier:
/* get the conversion qualifier */
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
qualifier = 0;
lib: make _tolower() public This function is required by *printf and kstrto* functions that are located in the different modules. This patch makes _tolower() public. However, it's good idea to not use the helper outside of mentioned functions. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 08:13:20 +08:00
if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
lib/vsprintf.c: remove %Z support Now that %z is standartised in C99 there is no reason to support %Z. Unlike %L it doesn't even make format strings smaller. Use BUILD_BUG_ON in a couple ATM drivers. In case anyone didn't notice lib/vsprintf.o is about half of SLUB which is in my opinion is quite an achievement. Hopefully this patch inspires someone else to trim vsprintf.c more. Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-28 06:30:02 +08:00
*fmt == 'z' || *fmt == 't') {
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
qualifier = *fmt++;
if (unlikely(qualifier == *fmt)) {
if (qualifier == 'l') {
qualifier = 'L';
printk: add support of hh length modifier for printk Impact: new feature, extend vsprintf format strings hh is used as length modifier for signed char or unsigned char. It is supported by glibc, we add kernel support now. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: torvalds@linux-foundation.org Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49CC9739.30107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:07:05 +08:00
++fmt;
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
} else if (qualifier == 'h') {
qualifier = 'H';
printk: add support of hh length modifier for printk Impact: new feature, extend vsprintf format strings hh is used as length modifier for signed char or unsigned char. It is supported by glibc, we add kernel support now. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: torvalds@linux-foundation.org Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49CC9739.30107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:07:05 +08:00
++fmt;
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
}
}
/* default base */
spec->base = 10;
switch (*fmt) {
case 'c':
spec->type = FORMAT_TYPE_CHAR;
return ++fmt - start;
case 's':
spec->type = FORMAT_TYPE_STR;
return ++fmt - start;
case 'p':
spec->type = FORMAT_TYPE_PTR;
lib/vsprintf.c: consume 'p' in format_decode It seems a little simpler to consume the p from a %p specifier in format_decode, just as it is done for the surrounding %c, %s and %% cases. While there, delete a redundant and misplaced comment. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 07:01:37 +08:00
return ++fmt - start;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case '%':
spec->type = FORMAT_TYPE_PERCENT_CHAR;
return ++fmt - start;
/* integer number formats - set up the flags and "break" */
case 'o':
spec->base = 8;
break;
case 'x':
spec->flags |= SMALL;
lib/vsprintf: Mark expected switch fall-through In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Link: http://lkml.kernel.org/r/20180216210711.79901-9-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:11 +08:00
/* fall through */
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case 'X':
spec->base = 16;
break;
case 'd':
case 'i':
vsprintf: fix bug in negative value printing Sitsofe Wheeler found and bisected that while unifying the vsprintf format decoding in: fef20d9: vsprintf: unify the format decoding layer for its 3 users The sign flag has been dropped out in favour of precise types (ie: LONG/ULONG). But the format helper number() still needs this flag to keep track of the signedness unless it will consider all numbers as unsigned. Also add an explicit cast to int (for %d) while parsing with va_arg() to ensure the highest bit is well extended on the 64 bits number that hosts the value in case of negative values. Reported-Bisected-Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <20090309201503.GA5010@nowhere> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-10 04:15:04 +08:00
spec->flags |= SIGN;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case 'u':
printk: add %I4, %I6, %i4, %i6 format specifiers For use in printing IPv4, or IPv6 addresses in the usual way: %i4 and %I4 are currently equivalent and print the address in dot-separated decimal x.x.x.x %I6 prints 16-bit network order hex with colon separators: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx %i6 omits the colons. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-30 03:49:58 +08:00
break;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
vsprintf: remove %n handling All in-kernel users of %n in format strings have now been removed and the %n directive is ignored. Remove the handling of %n so that it is treated the same as any other invalid format string directive. Keep a warning in place to deter new instances of %n in format strings. Signed-off-by: Ryan Mallon <rmallon@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 05:48:37 +08:00
case 'n':
/*
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
* Since %n poses a greater security risk than
* utility, treat it as any other invalid or
* unsupported format specifier.
vsprintf: remove %n handling All in-kernel users of %n in format strings have now been removed and the %n directive is ignored. Remove the handling of %n so that it is treated the same as any other invalid format string directive. Keep a warning in place to deter new instances of %n in format strings. Signed-off-by: Ryan Mallon <rmallon@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 05:48:37 +08:00
*/
/* Fall-through */
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
default:
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
spec->type = FORMAT_TYPE_INVALID;
return fmt - start;
vsprintf: add support for '%pS' and '%pF' pointer formats They print out a pointer in symbolic format, if possible (ie using symbolic KALLSYMS information). The '%pS' format is for regular direct pointers (which can point to data or code and that you find on the stack during backtraces etc), while '%pF' is for C function pointer types. On most architectures, the two mean exactly the same thing, but some architectures use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF' code automatically does the appropriate function descriptor dereference on such architectures. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:43:12 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
if (qualifier == 'L')
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
spec->type = FORMAT_TYPE_LONG_LONG;
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
else if (qualifier == 'l') {
lib/vsprintf.c: eliminate some branches Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few instructions by making SIGN have the value 1 instead of 2, and then use arithmetic instead of branches for computing the right spec->type. It's a little hacky, but certainly in the same spirit as SMALL needing to have the value 0x20. For example for the spec->qualifier == 'l' case, gcc now generates 75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx 762: 83 e2 01 and $0x1,%edx 765: 83 c2 09 add $0x9,%edx 768: 88 13 mov %dl,(%rbx) instead of 763: 0f b6 53 01 movzbl 0x1(%rbx),%edx 767: 83 e2 02 and $0x2,%edx 76a: 80 fa 01 cmp $0x1,%dl 76d: 19 d2 sbb %edx,%edx 76f: 83 c2 0a add $0xa,%edx 772: 88 13 mov %dl,(%rbx) Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:02 +08:00
BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
lib/vsprintf.c: remove %Z support Now that %z is standartised in C99 there is no reason to support %Z. Unlike %L it doesn't even make format strings smaller. Use BUILD_BUG_ON in a couple ATM drivers. In case anyone didn't notice lib/vsprintf.o is about half of SLUB which is in my opinion is quite an achievement. Hopefully this patch inspires someone else to trim vsprintf.c more. Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-28 06:30:02 +08:00
} else if (qualifier == 'z') {
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
spec->type = FORMAT_TYPE_SIZE_T;
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
} else if (qualifier == 't') {
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
spec->type = FORMAT_TYPE_PTRDIFF;
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
} else if (qualifier == 'H') {
lib/vsprintf.c: eliminate some branches Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few instructions by making SIGN have the value 1 instead of 2, and then use arithmetic instead of branches for computing the right spec->type. It's a little hacky, but certainly in the same spirit as SMALL needing to have the value 0x20. For example for the spec->qualifier == 'l' case, gcc now generates 75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx 762: 83 e2 01 and $0x1,%edx 765: 83 c2 09 add $0x9,%edx 768: 88 13 mov %dl,(%rbx) instead of 763: 0f b6 53 01 movzbl 0x1(%rbx),%edx 767: 83 e2 02 and $0x2,%edx 76a: 80 fa 01 cmp $0x1,%dl 76d: 19 d2 sbb %edx,%edx 76f: 83 c2 0a add $0xa,%edx 772: 88 13 mov %dl,(%rbx) Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:02 +08:00
BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
lib/vsprintf.c: expand field_width to 24 bits Maurizio Lombardi reported a problem [1] with the %pb extension: It doesn't work for sufficiently large bitmaps, since the size is stashed in the field_width field of the struct printf_spec, which is currently an s16. Concretely, this manifested itself in /sys/bus/pseudo/drivers/scsi_debug/map being empty, since the bitmap printer got a size of 0, which is the 16 bit truncation of the actual bitmap size. We do want to keep struct printf_spec at 8 bytes so that it can cheaply be passed by value. The qualifier field is only used for internal bookkeeping in format_decode, so we might as well use a local variable for that. This gives us an additional 8 bits, which we can then use for the field width. To stay in 8 bytes, we need to do a little rearranging and make the type member a bitfield as well. For consistency, change all the members to bit fields. gcc doesn't generate much worse code with these changes (in fact, bloat-o-meter says we save 300 bytes - which I think is a little surprising). I didn't find a BUILD_BUG/compiletime_assertion/... which would work outside function context, so for now I just open-coded it. [1] http://thread.gmane.org/gmane.linux.kernel/2034835 [akpm@linux-foundation.org: avoid open-coded BUILD_BUG_ON] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reported-by: Maurizio Lombardi <mlombard@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:37 +08:00
} else if (qualifier == 'h') {
lib/vsprintf.c: eliminate some branches Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few instructions by making SIGN have the value 1 instead of 2, and then use arithmetic instead of branches for computing the right spec->type. It's a little hacky, but certainly in the same spirit as SMALL needing to have the value 0x20. For example for the spec->qualifier == 'l' case, gcc now generates 75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx 762: 83 e2 01 and $0x1,%edx 765: 83 c2 09 add $0x9,%edx 768: 88 13 mov %dl,(%rbx) instead of 763: 0f b6 53 01 movzbl 0x1(%rbx),%edx 767: 83 e2 02 and $0x2,%edx 76a: 80 fa 01 cmp $0x1,%dl 76d: 19 d2 sbb %edx,%edx 76f: 83 c2 0a add $0xa,%edx 772: 88 13 mov %dl,(%rbx) Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:02 +08:00
BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
} else {
lib/vsprintf.c: eliminate some branches Since FORMAT_TYPE_INT is simply 1 more than FORMAT_TYPE_UINT, and similarly for BYTE/UBYTE, SHORT/USHORT, LONG/ULONG, we can eliminate a few instructions by making SIGN have the value 1 instead of 2, and then use arithmetic instead of branches for computing the right spec->type. It's a little hacky, but certainly in the same spirit as SMALL needing to have the value 0x20. For example for the spec->qualifier == 'l' case, gcc now generates 75e: 0f b6 53 01 movzbl 0x1(%rbx),%edx 762: 83 e2 01 and $0x1,%edx 765: 83 c2 09 add $0x9,%edx 768: 88 13 mov %dl,(%rbx) instead of 763: 0f b6 53 01 movzbl 0x1(%rbx),%edx 767: 83 e2 02 and $0x2,%edx 76a: 80 fa 01 cmp $0x1,%dl 76d: 19 d2 sbb %edx,%edx 76f: 83 c2 0a add $0xa,%edx 772: 88 13 mov %dl,(%rbx) Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 07:17:02 +08:00
BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
vsprintf: split out '%p' handling logic The actual code is the same, just split out into a helper function. This makes it easier to read, and allows for simple future extension of %p handling. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:16:15 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
return ++fmt - start;
vsprintf: split out '%p' handling logic The actual code is the same, just split out into a helper function. This makes it easier to read, and allows for simple future extension of %p handling. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 07:16:15 +08:00
}
lib/vsprintf.c: warn about too large precisions and field widths The field width is overloaded to pass some extra information for some %p extensions (e.g. #bits for %pb). But we might silently truncate the passed value when we stash it in struct printf_spec (see e.g. "lib/vsprintf.c: expand field_width to 24 bits"). Hopefully 23 value bits should now be enough for everybody, but if not, let's make some noise. Do the same for the precision. In both cases, clamping seems more sensible than truncating. While, according to POSIX, "A negative precision is taken as if the precision were omitted.", the kernel's printf has always treated that case as if the precision was 0, so we use that as lower bound. For the field width, the smallest representable value is actually -(1<<23), but a negative field width means 'set the LEFT flag and use the absolute value', so we want the absolute value to fit. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:44 +08:00
static void
set_field_width(struct printf_spec *spec, int width)
{
spec->field_width = width;
if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
}
}
static void
set_precision(struct printf_spec *spec, int prec)
{
spec->precision = prec;
if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
spec->precision = clamp(prec, 0, PRECISION_MAX);
}
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/**
* vsnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
lib/vsprintf.c: update documentation %n is no longer just ignored; it results in early return from vsnprintf. Also add a request to add test cases for future %p extensions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Martin Kletzander <mkletzan@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:35 +08:00
* This function generally follows C99 vsnprintf, but has some
* extensions and a few limitations:
*
kernel-api.rst: fix output of the vsnprintf() documentation The vsnprintf() kernel-doc comment uses % character with a special meaning other than escaping a constant. As ReST already defines ``literal`` as an escape sequence, let's make kernel-doc handle it, and use it at lib/vsprintf.c. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-03-31 04:11:33 +08:00
* - ``%n`` is unsupported
* - ``%p*`` is handled by pointer()
printk: synchronize %p formatting documentation Move all pointer-formatting documentation to one place in the code and one place in the documentation instead of keeping it in three places with different level of completeness. Documentation/printk-formats.txt has detailed information about each modifier, docstring above pointer() has short descriptions of them (as that is the function dealing with %p) and docstring above vsprintf() is removed as redundant. Both docstrings in the code that were modified are updated with a reminder of updating the documentation upon any further change. [akpm@linux-foundation.org: fix comment] Signed-off-by: Martin Kletzander <mkletzan@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:17 +08:00
*
vsprintf: Fix a dangling documentation reference A reference to printk-formats.txt didn't get updated when the file moved; fix that. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-22 03:39:45 +08:00
* See pointer() or Documentation/core-api/printk-formats.rst for more
printk: synchronize %p formatting documentation Move all pointer-formatting documentation to one place in the code and one place in the documentation instead of keeping it in three places with different level of completeness. Documentation/printk-formats.txt has detailed information about each modifier, docstring above pointer() has short descriptions of them (as that is the function dealing with %p) and docstring above vsprintf() is removed as redundant. Both docstrings in the code that were modified are updated with a reminder of updating the documentation upon any further change. [akpm@linux-foundation.org: fix comment] Signed-off-by: Martin Kletzander <mkletzan@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:17 +08:00
* extensive description.
Add kerneldoc documentation for new printk format extensions Add documentation in kerneldoc for new printk format extensions This patch documents the new %pS/%pF options in printk in kernel doc. Hope I didn't miss any other extension. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 13:02:02 +08:00
*
kernel-api.rst: fix output of the vsnprintf() documentation The vsnprintf() kernel-doc comment uses % character with a special meaning other than escaping a constant. As ReST already defines ``literal`` as an escape sequence, let's make kernel-doc handle it, and use it at lib/vsprintf.c. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-03-31 04:11:33 +08:00
* **Please update the documentation in both places when making changes**
lib/vsprintf.c: remind people to update Documentation/printk-formats.txt when adding printk formats Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 05:40:25 +08:00
*
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* The return value is the number of characters which would
* be generated for the given input, excluding the trailing
* '\0', as per ISO C99. If you want to have the exact
* number of characters written into @buf as return value
[PATCH] Numerous fixes to kernel-doc info in source files. A variety of (mostly) innocuous fixes to the embedded kernel-doc content in source files, including: * make multi-line initial descriptions single line * denote some function names, constants and structs as such * change erroneous opening '/*' to '/**' in a few places * reword some text for clarity Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10 17:45:59 +08:00
* (not including the trailing '\0'), use vscnprintf(). If the
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* return is greater than or equal to @size, the resulting
* string is truncated.
*
vsprintf: make comment about vs{n,cn,}printf more understandable "You probably want ... instead." sounds like a recommendation better not to use the v... functions. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-04-06 22:49:04 +08:00
* If you're not already dealing with a va_list consider using snprintf().
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
unsigned long long num;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
char *str, *end;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
struct printf_spec spec = {0};
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
/* Reject out-of-range values early. Large positive sizes are
used for unknown buffer sizes. */
lib/vsprintf.c: improve sanity check in vsnprintf() On 64 bit, size may very well be huge even if bit 31 happens to be 0. Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a 3 GiB one. So cap at INT_MAX as was probably the intention all along. This is also the made-up value passed by sprintf and vsprintf. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 07:01:39 +08:00
if (WARN_ON_ONCE(size > INT_MAX))
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return 0;
str = buf;
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
end = buf + size;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
/* Make sure end is always >= buf */
if (end < buf) {
end = ((void *)-1);
size = end - buf;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
while (*fmt) {
const char *old_fmt = fmt;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
int read = format_decode(fmt, &spec);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
fmt += read;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
switch (spec.type) {
case FORMAT_TYPE_NONE: {
int copy = read;
if (str < end) {
if (copy > end - str)
copy = end - str;
memcpy(str, old_fmt, copy);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
str += read;
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
vsprintf: unify the format decoding layer for its 3 users, cleanup Impact: cleanup Rename FORMAT_TYPE_WITDH to => FORMAT_TYPE_WIDTH Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
case FORMAT_TYPE_WIDTH:
lib/vsprintf.c: warn about too large precisions and field widths The field width is overloaded to pass some extra information for some %p extensions (e.g. #bits for %pb). But we might silently truncate the passed value when we stash it in struct printf_spec (see e.g. "lib/vsprintf.c: expand field_width to 24 bits"). Hopefully 23 value bits should now be enough for everybody, but if not, let's make some noise. Do the same for the precision. In both cases, clamping seems more sensible than truncating. While, according to POSIX, "A negative precision is taken as if the precision were omitted.", the kernel's printf has always treated that case as if the precision was 0, so we use that as lower bound. For the field width, the smallest representable value is actually -(1<<23), but a negative field width means 'set the LEFT flag and use the absolute value', so we want the absolute value to fit. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:44 +08:00
set_field_width(&spec, va_arg(args, int));
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PRECISION:
lib/vsprintf.c: warn about too large precisions and field widths The field width is overloaded to pass some extra information for some %p extensions (e.g. #bits for %pb). But we might silently truncate the passed value when we stash it in struct printf_spec (see e.g. "lib/vsprintf.c: expand field_width to 24 bits"). Hopefully 23 value bits should now be enough for everybody, but if not, let's make some noise. Do the same for the precision. In both cases, clamping seems more sensible than truncating. While, according to POSIX, "A negative precision is taken as if the precision were omitted.", the kernel's printf has always treated that case as if the precision was 0, so we use that as lower bound. For the field width, the smallest representable value is actually -(1<<23), but a negative field width means 'set the LEFT flag and use the absolute value', so we want the absolute value to fit. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:44 +08:00
set_precision(&spec, va_arg(args, int));
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
case FORMAT_TYPE_CHAR: {
char c;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (!(spec.flags & LEFT)) {
while (--spec.field_width > 0) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (str < end)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*str = ' ';
++str;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
}
}
c = (unsigned char) va_arg(args, int);
if (str < end)
*str = c;
++str;
while (--spec.field_width > 0) {
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (str < end)
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
*str = ' ';
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
++str;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
}
break;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_STR:
str = string(str, end, va_arg(args, char *), spec);
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PTR:
lib/vsprintf.c: consume 'p' in format_decode It seems a little simpler to consume the p from a %p specifier in format_decode, just as it is done for the surrounding %c, %s and %% cases. While there, delete a redundant and misplaced comment. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 07:01:37 +08:00
str = pointer(fmt, str, end, va_arg(args, void *),
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
spec);
while (isalnum(*fmt))
fmt++;
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PERCENT_CHAR:
if (str < end)
*str = '%';
++str;
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_INVALID:
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
/*
* Presumably the arguments passed gcc's type
* checking, but there is no safe or sane way
* for us to continue parsing the format and
* fetching from the va_list; the remaining
* specifiers and arguments would be out of
* sync.
*/
goto out;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
default:
switch (spec.type) {
case FORMAT_TYPE_LONG_LONG:
num = va_arg(args, long long);
break;
case FORMAT_TYPE_ULONG:
num = va_arg(args, unsigned long);
break;
case FORMAT_TYPE_LONG:
num = va_arg(args, long);
break;
case FORMAT_TYPE_SIZE_T:
lib/vsprintf.c: fix handling of %zd when using ssize_t Documentation/printk-formats.txt says to use %zd for a ssize_t argument and some drivers do. Unfortunately this prints a positive number for negative values eg: tpm_tis 70030000.tpm_tis: tpm_transmit: tpm_send: error 4294967234 Add a case to va_args a ssize_t type if the interpretation should be signed. Tested on PPC32. Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 07:59:58 +08:00
if (spec.flags & SIGN)
num = va_arg(args, ssize_t);
else
num = va_arg(args, size_t);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
case FORMAT_TYPE_PTRDIFF:
num = va_arg(args, ptrdiff_t);
break;
printk: add support of hh length modifier for printk Impact: new feature, extend vsprintf format strings hh is used as length modifier for signed char or unsigned char. It is supported by glibc, we add kernel support now. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: torvalds@linux-foundation.org Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49CC9739.30107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:07:05 +08:00
case FORMAT_TYPE_UBYTE:
num = (unsigned char) va_arg(args, int);
break;
case FORMAT_TYPE_BYTE:
num = (signed char) va_arg(args, int);
break;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_USHORT:
num = (unsigned short) va_arg(args, int);
break;
case FORMAT_TYPE_SHORT:
num = (short) va_arg(args, int);
break;
vsprintf: fix bug in negative value printing Sitsofe Wheeler found and bisected that while unifying the vsprintf format decoding in: fef20d9: vsprintf: unify the format decoding layer for its 3 users The sign flag has been dropped out in favour of precise types (ie: LONG/ULONG). But the format helper number() still needs this flag to keep track of the signedness unless it will consider all numbers as unsigned. Also add an explicit cast to int (for %d) while parsing with va_arg() to ensure the highest bit is well extended on the 64 bits number that hosts the value in case of negative values. Reported-Bisected-Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <20090309201503.GA5010@nowhere> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-10 04:15:04 +08:00
case FORMAT_TYPE_INT:
num = (int) va_arg(args, int);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
default:
num = va_arg(args, unsigned int);
}
str = number(str, end, num, spec);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
out:
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
if (size > 0) {
if (str < end)
*str = '\0';
else
Fix vsnprintf off-by-one bug The recent vsnprintf() fix introduced an off-by-one, and it's now possible to overrun the target buffer by one byte. The "end" pointer points to past the end of the buffer, so if we have to truncate the result, it needs to be done though "end[-1]". [ This is just an alternate and simpler patch to one proposed by Andrew and Jeremy, who actually noticed the problem ] Acked-by: Andrew Morton <akpm@osdl.org> Acked-by: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 08:09:34 +08:00
end[-1] = '\0';
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
[PATCH] Fix bounds check in vsnprintf, to allow for a 0 size and NULL buffer This change allows callers to use a 0-byte buffer and a NULL buffer pointer with vsnprintf, so it can be used to determine how large the resulting formatted string will be. Previously the code effectively treated a size of 0 as a size of 4G (on 32-bit systems), with other checks preventing it from actually trying to emit the string - but the terminal \0 would still be written, which would crash if the buffer is NULL. This change changes the boundary check so that 'end' points to the putative location of the terminal '\0', which is only written if size > 0. vsnprintf still allows the buffer size to be set very large, to allow unbounded buffer sizes (to implement sprintf, etc). [akpm@osdl.org: fix long-vs-longlong confusion] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 20:49:17 +08:00
/* the trailing null byte doesn't count towards the total */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return str-buf;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
EXPORT_SYMBOL(vsnprintf);
/**
* vscnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The return value is the number of characters which have been written into
lib/vsprintf.c: fix vscnprintf() if @size is == 0 vscnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. This change based on the code of commit b903c0b8899b46829a9b80ba55b61079b35940ec ("lib: fix scnprintf() if @size is == 0") moves the real fix into vscnprinf() from scnprintf() and makes scnprintf() call vscnprintf(), thus avoid code duplication. Signed-off-by: Anton Arapov <aarapov@redhat.com> Acked-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:59:49 +08:00
* the @buf not including the trailing '\0'. If @size is == 0 the function
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* returns 0.
*
vsprintf: make comment about vs{n,cn,}printf more understandable "You probably want ... instead." sounds like a recommendation better not to use the v... functions. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-04-06 22:49:04 +08:00
* If you're not already dealing with a va_list consider using scnprintf().
Add kerneldoc documentation for new printk format extensions Add documentation in kerneldoc for new printk format extensions This patch documents the new %pS/%pF options in printk in kernel doc. Hope I didn't miss any other extension. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 13:02:02 +08:00
*
* See the vsnprintf() documentation for format string extensions over C99.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
int i;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
i = vsnprintf(buf, size, fmt, args);
lib/vsprintf.c: fix vscnprintf() if @size is == 0 vscnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. This change based on the code of commit b903c0b8899b46829a9b80ba55b61079b35940ec ("lib: fix scnprintf() if @size is == 0") moves the real fix into vscnprinf() from scnprintf() and makes scnprintf() call vscnprintf(), thus avoid code duplication. Signed-off-by: Anton Arapov <aarapov@redhat.com> Acked-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:59:49 +08:00
if (likely(i < size))
return i;
if (size != 0)
return size - 1;
return 0;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
EXPORT_SYMBOL(vscnprintf);
/**
* snprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The return value is the number of characters which would be
* generated for the given input, excluding the trailing null,
* as per ISO C99. If the return is greater than or equal to
* @size, the resulting string is truncated.
Add kerneldoc documentation for new printk format extensions Add documentation in kerneldoc for new printk format extensions This patch documents the new %pS/%pF options in printk in kernel doc. Hope I didn't miss any other extension. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 13:02:02 +08:00
*
* See the vsnprintf() documentation for format string extensions over C99.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int snprintf(char *buf, size_t size, const char *fmt, ...)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
va_list args;
int i;
va_start(args, fmt);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
i = vsnprintf(buf, size, fmt, args);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
va_end(args);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return i;
}
EXPORT_SYMBOL(snprintf);
/**
* scnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The return value is the number of characters written into @buf not including
lib: fix scnprintf() if @size is == 0 scnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 05:22:50 +08:00
* the trailing '\0'. If @size is == 0 the function returns 0.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int scnprintf(char *buf, size_t size, const char *fmt, ...)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
va_list args;
int i;
va_start(args, fmt);
lib/vsprintf.c: fix vscnprintf() if @size is == 0 vscnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. This change based on the code of commit b903c0b8899b46829a9b80ba55b61079b35940ec ("lib: fix scnprintf() if @size is == 0") moves the real fix into vscnprinf() from scnprintf() and makes scnprintf() call vscnprintf(), thus avoid code duplication. Signed-off-by: Anton Arapov <aarapov@redhat.com> Acked-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:59:49 +08:00
i = vscnprintf(buf, size, fmt, args);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
va_end(args);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
lib/vsprintf.c: fix vscnprintf() if @size is == 0 vscnprintf() should return 0 if @size is == 0. Update the comment for it, as @size is unsigned. This change based on the code of commit b903c0b8899b46829a9b80ba55b61079b35940ec ("lib: fix scnprintf() if @size is == 0") moves the real fix into vscnprinf() from scnprintf() and makes scnprintf() call vscnprintf(), thus avoid code duplication. Signed-off-by: Anton Arapov <aarapov@redhat.com> Acked-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:59:49 +08:00
return i;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
EXPORT_SYMBOL(scnprintf);
/**
* vsprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The function returns the number of characters written
[PATCH] Numerous fixes to kernel-doc info in source files. A variety of (mostly) innocuous fixes to the embedded kernel-doc content in source files, including: * make multi-line initial descriptions single line * denote some function names, constants and structs as such * change erroneous opening '/*' to '/**' in a few places * reword some text for clarity Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10 17:45:59 +08:00
* into @buf. Use vsnprintf() or vscnprintf() in order to avoid
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* buffer overflows.
*
vsprintf: make comment about vs{n,cn,}printf more understandable "You probably want ... instead." sounds like a recommendation better not to use the v... functions. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-04-06 22:49:04 +08:00
* If you're not already dealing with a va_list consider using sprintf().
Add kerneldoc documentation for new printk format extensions Add documentation in kerneldoc for new printk format extensions This patch documents the new %pS/%pF options in printk in kernel doc. Hope I didn't miss any other extension. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 13:02:02 +08:00
*
* See the vsnprintf() documentation for format string extensions over C99.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
int vsprintf(char *buf, const char *fmt, va_list args)
{
return vsnprintf(buf, INT_MAX, fmt, args);
}
EXPORT_SYMBOL(vsprintf);
/**
* sprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The function returns the number of characters written
[PATCH] Numerous fixes to kernel-doc info in source files. A variety of (mostly) innocuous fixes to the embedded kernel-doc content in source files, including: * make multi-line initial descriptions single line * denote some function names, constants and structs as such * change erroneous opening '/*' to '/**' in a few places * reword some text for clarity Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-10 17:45:59 +08:00
* into @buf. Use snprintf() or scnprintf() in order to avoid
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* buffer overflows.
Add kerneldoc documentation for new printk format extensions Add documentation in kerneldoc for new printk format extensions This patch documents the new %pS/%pF options in printk in kernel doc. Hope I didn't miss any other extension. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 13:02:02 +08:00
*
* See the vsnprintf() documentation for format string extensions over C99.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*/
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int sprintf(char *buf, const char *fmt, ...)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
va_list args;
int i;
va_start(args, fmt);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
i = vsnprintf(buf, INT_MAX, fmt, args);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
va_end(args);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return i;
}
EXPORT_SYMBOL(sprintf);
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
#ifdef CONFIG_BINARY_PRINTF
/*
* bprintf service:
* vbin_printf() - VA arguments to binary data
* bstr_printf() - Binary data to text string
*/
/**
* vbin_printf - Parse a format string and place args' binary value in a buffer
* @bin_buf: The buffer to place args' binary value
* @size: The size of the buffer(by words(32bits), not characters)
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The format follows C99 vsnprintf, except %n is ignored, and its argument
Documentation: Docbook: Fix generated DocBook/kernel-api.xml This patch fix spelling typo found in DocBook/kernel-api.xml. It is because the file is generated from the source comments, I have to fix the comments in source codes. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-09-09 00:27:23 +08:00
* is skipped.
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
*
* The return value is the number of words(32bits) which would be generated for
* the given input.
*
* NOTE:
* If the return value is greater than @size, the resulting bin_buf is NOT
* valid for bstr_printf().
*/
int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
{
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
struct printf_spec spec = {0};
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
char *str, *end;
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
int width;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
str = (char *)bin_buf;
end = (char *)(bin_buf + size);
#define save_arg(type) \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
({ \
unsigned long long value; \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (sizeof(type) == 8) { \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
unsigned long long val8; \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
str = PTR_ALIGN(str, sizeof(u32)); \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
val8 = va_arg(args, unsigned long long); \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (str + sizeof(type) <= end) { \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
*(u32 *)str = *(u32 *)&val8; \
*(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
} \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
value = val8; \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
} else { \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
unsigned int val4; \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
str = PTR_ALIGN(str, sizeof(type)); \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
val4 = va_arg(args, int); \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (str + sizeof(type) <= end) \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
*(typeof(type) *)str = (type)(long)val4; \
value = (unsigned long long)val4; \
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
} \
str += sizeof(type); \
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
value; \
})
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
while (*fmt) {
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
int read = format_decode(fmt, &spec);
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
fmt += read;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
switch (spec.type) {
case FORMAT_TYPE_NONE:
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
case FORMAT_TYPE_PERCENT_CHAR:
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
case FORMAT_TYPE_INVALID:
goto out;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
vsprintf: unify the format decoding layer for its 3 users, cleanup Impact: cleanup Rename FORMAT_TYPE_WITDH to => FORMAT_TYPE_WIDTH Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
case FORMAT_TYPE_WIDTH:
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PRECISION:
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
width = (int)save_arg(int);
/* Pointers may require the width */
if (*fmt == 'p')
set_field_width(&spec, width);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
case FORMAT_TYPE_CHAR:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(char);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
case FORMAT_TYPE_STR: {
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
const char *save_str = va_arg(args, char *);
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
const char *err_msg;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
size_t len;
vsprintf: pre-calculate final string length for later use Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:56 +08:00
vsprintf: Prevent crash when dereferencing invalid pointers We already prevent crash when dereferencing some obviously broken pointers. But the handling is not consistent. Sometimes we print "(null)" only for pure NULL pointer, sometimes for pointers in the first page and sometimes also for pointers in the last page (error codes). Note that printk() call this code under logbuf_lock. Any recursive printks are redirected to the printk_safe implementation and the messages are stored into per-CPU buffers. These buffers might be eventually flushed in printk_safe_flush_on_panic() but it is not guaranteed. This patch adds a check using probe_kernel_read(). It is not a full-proof test. But it should help to see the error message in 99% situations where the kernel would silently crash otherwise. Also it makes the error handling unified for "%s" and the many %p* specifiers that need to read the data from a given address. We print: + (null) when accessing data on pure pure NULL address + (efault) when accessing data on an invalid address It does not affect the %p* specifiers that just print the given address in some form, namely %pF, %pf, %pS, %ps, %pB, %pK, %px, and plain %p. Note that we print (efault) from security reasons. In fact, the real address can be seen only by %px or eventually %pK. Link: http://lkml.kernel.org/r/20190417115350.20479-9-pmladek@suse.com To: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Tobin C . Harding" <me@tobin.cc> Cc: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-17 19:53:48 +08:00
err_msg = check_pointer_msg(save_str);
if (err_msg)
save_str = err_msg;
vsprintf: pre-calculate final string length for later use Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:56 +08:00
len = strlen(save_str) + 1;
if (str + len < end)
memcpy(str, save_str, len);
str += len;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PTR:
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
/* Dereferenced pointers must be done now */
switch (*fmt) {
/* Dereference of functions is still OK */
case 'S':
case 's':
vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK) Commit 841a915d20c7b2 ("printf: Do not have bprintf dereference pointers") would preprocess various pointers that are dereferenced in the bprintf() because the recording and printing are done at two different times. Some pointers stayed dereferenced in the ring buffer because user space could handle them (namely "%pS" and friends). Pointers that are not dereferenced should not be processed immediately but instead just saved directly. Cc: stable@vger.kernel.org Fixes: 841a915d20c7b2 ("printf: Do not have bprintf dereference pointers") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-04 02:38:53 +08:00
case 'x':
case 'K':
printf: add support for printing symbolic error names It has been suggested several times to extend vsnprintf() to be able to convert the numeric value of ENOSPC to print "ENOSPC". This implements that as a %p extension: With %pe, one can do if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %pe\n", foo); return PTR_ERR(foo); } instead of what is seen in quite a few places in the kernel: if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %ld\n", PTR_ERR(foo)); return PTR_ERR(foo); } If the value passed to %pe is an ERR_PTR, but the library function errname() added here doesn't know about the value, the value is simply printed in decimal. If the value passed to %pe is not an ERR_PTR, we treat it as an ordinary %p and thus print the hashed value (passing non-ERR_PTR values to %pe indicates a bug in the caller, but we can't do much about that). With my embedded hat on, and because it's not very invasive to do, I've made it possible to remove this. The errname() function and associated lookup tables take up about 3K. For most, that's probably quite acceptable and a price worth paying for more readable dmesg (once this starts getting used), while for those that disable printk() it's of very little use - I don't see a procfs/sysfs/seq_printf() file reasonably making use of this - and they clearly want to squeeze vmlinux as much as possible. Hence the default y if PRINTK. The symbols to include have been found by massaging the output of find arch include -iname 'errno*.h' | xargs grep -E 'define\s*E' In the cases where some common aliasing exists (e.g. EAGAIN=EWOULDBLOCK on all platforms, EDEADLOCK=EDEADLK on most), I've moved the more popular one (in terms of 'git grep -w Efoo | wc) to the bottom so that one takes precedence. Link: http://lkml.kernel.org/r/20191015190706.15989-1-linux@rasmusvillemoes.dk To: "Jonathan Corbet" <corbet@lwn.net> To: linux-kernel@vger.kernel.org Cc: "Andy Shevchenko" <andy.shevchenko@gmail.com> Cc: "Andrew Morton" <akpm@linux-foundation.org> Cc: "Joe Perches" <joe@perches.com> Cc: linux-doc@vger.kernel.org Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Uwe Kleine-König <uwe@kleine-koenig.org> Reviewed-by: Petr Mladek <pmladek@suse.com> [andy.shevchenko@gmail.com: use abs()] Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-16 03:07:05 +08:00
case 'e':
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
save_arg(void *);
break;
default:
if (!isalnum(*fmt)) {
save_arg(void *);
break;
}
str = pointer(fmt, str, end, va_arg(args, void *),
spec);
if (str + 1 < end)
*str++ = '\0';
else
end[-1] = '\0'; /* Must be nul terminated */
}
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
/* skip all alphanumeric pointer suffixes */
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
while (isalnum(*fmt))
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
fmt++;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
default:
switch (spec.type) {
case FORMAT_TYPE_LONG_LONG:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(long long);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
case FORMAT_TYPE_ULONG:
case FORMAT_TYPE_LONG:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(unsigned long);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
case FORMAT_TYPE_SIZE_T:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(size_t);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
case FORMAT_TYPE_PTRDIFF:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(ptrdiff_t);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
printk: add support of hh length modifier for printk Impact: new feature, extend vsprintf format strings hh is used as length modifier for signed char or unsigned char. It is supported by glibc, we add kernel support now. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: torvalds@linux-foundation.org Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49CC9739.30107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:07:05 +08:00
case FORMAT_TYPE_UBYTE:
case FORMAT_TYPE_BYTE:
save_arg(char);
break;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_USHORT:
case FORMAT_TYPE_SHORT:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(short);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
default:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
save_arg(int);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
}
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
}
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
out:
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
#undef save_arg
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
}
EXPORT_SYMBOL_GPL(vbin_printf);
/**
* bstr_printf - Format a string from binary arguments and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @bin_buf: Binary arguments for the format string
*
* This function like C99 vsnprintf, but the difference is that vsnprintf gets
* arguments from stack, and bstr_printf gets arguments from @bin_buf which is
* a binary buffer that generated by vbin_printf.
*
* The format follows C99 vsnprintf, but has some extensions:
vsnprintf: remove duplicate comment of vsnprintf Remove the duplicate comment of bstr_printf that is the same as the vsnprintf. Add the 's' option to the comment for the pointer function. This is more of an internal function so the little duplication of the comment here is OK. Reported-by: Zhaolei <zhaolei@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-17 21:27:29 +08:00
* see vsnprintf comment for details.
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
*
* The return value is the number of characters which would
* be generated for the given input, excluding the trailing
* '\0', as per ISO C99. If you want to have the exact
* number of characters written into @buf as return value
* (not including the trailing '\0'), use vscnprintf(). If the
* return is greater than or equal to @size, the resulting
* string is truncated.
*/
int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
{
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
struct printf_spec spec = {0};
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
char *str, *end;
const char *args = (const char *)bin_buf;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
lib/vsprintf.c: also improve sanity check in bstr_printf() Quoting from 2aa2f9e21e4e ("lib/vsprintf.c: improve sanity check in vsnprintf()"): On 64 bit, size may very well be huge even if bit 31 happens to be 0. Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a 3 GiB one. So cap at INT_MAX as was probably the intention all along. This is also the made-up value passed by sprintf and vsprintf. I should have seen this copy-pasted instance back then, but let's just do it now. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:23 +08:00
if (WARN_ON_ONCE(size > INT_MAX))
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
return 0;
str = buf;
end = buf + size;
#define get_arg(type) \
({ \
typeof(type) value; \
if (sizeof(type) == 8) { \
args = PTR_ALIGN(args, sizeof(u32)); \
*(u32 *)&value = *(u32 *)args; \
*((u32 *)&value + 1) = *(u32 *)(args + 4); \
} else { \
args = PTR_ALIGN(args, sizeof(type)); \
value = *(typeof(type) *)args; \
} \
args += sizeof(type); \
value; \
})
/* Make sure end is always >= buf */
if (end < buf) {
end = ((void *)-1);
size = end - buf;
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
while (*fmt) {
const char *old_fmt = fmt;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
int read = format_decode(fmt, &spec);
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
fmt += read;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
switch (spec.type) {
case FORMAT_TYPE_NONE: {
int copy = read;
if (str < end) {
if (copy > end - str)
copy = end - str;
memcpy(str, old_fmt, copy);
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
str += read;
break;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
}
vsprintf: unify the format decoding layer for its 3 users, cleanup Impact: cleanup Rename FORMAT_TYPE_WITDH to => FORMAT_TYPE_WIDTH Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-14 19:08:50 +08:00
case FORMAT_TYPE_WIDTH:
lib/vsprintf.c: warn about too large precisions and field widths The field width is overloaded to pass some extra information for some %p extensions (e.g. #bits for %pb). But we might silently truncate the passed value when we stash it in struct printf_spec (see e.g. "lib/vsprintf.c: expand field_width to 24 bits"). Hopefully 23 value bits should now be enough for everybody, but if not, let's make some noise. Do the same for the precision. In both cases, clamping seems more sensible than truncating. While, according to POSIX, "A negative precision is taken as if the precision were omitted.", the kernel's printf has always treated that case as if the precision was 0, so we use that as lower bound. For the field width, the smallest representable value is actually -(1<<23), but a negative field width means 'set the LEFT flag and use the absolute value', so we want the absolute value to fit. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:44 +08:00
set_field_width(&spec, get_arg(int));
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PRECISION:
lib/vsprintf.c: warn about too large precisions and field widths The field width is overloaded to pass some extra information for some %p extensions (e.g. #bits for %pb). But we might silently truncate the passed value when we stash it in struct printf_spec (see e.g. "lib/vsprintf.c: expand field_width to 24 bits"). Hopefully 23 value bits should now be enough for everybody, but if not, let's make some noise. Do the same for the precision. In both cases, clamping seems more sensible than truncating. While, according to POSIX, "A negative precision is taken as if the precision were omitted.", the kernel's printf has always treated that case as if the precision was 0, so we use that as lower bound. For the field width, the smallest representable value is actually -(1<<23), but a negative field width means 'set the LEFT flag and use the absolute value', so we want the absolute value to fit. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 08:58:44 +08:00
set_precision(&spec, get_arg(int));
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
case FORMAT_TYPE_CHAR: {
char c;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
if (!(spec.flags & LEFT)) {
while (--spec.field_width > 0) {
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (str < end)
*str = ' ';
++str;
}
}
c = (unsigned char) get_arg(char);
if (str < end)
*str = c;
++str;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
while (--spec.field_width > 0) {
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (str < end)
*str = ' ';
++str;
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
}
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_STR: {
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
const char *str_arg = args;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
args += strlen(str_arg) + 1;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
str = string(str, end, (char *)str_arg, spec);
break;
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
}
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
case FORMAT_TYPE_PTR: {
bool process = false;
int copy, len;
/* Non function dereferences were already done */
switch (*fmt) {
case 'S':
case 's':
case 'F':
case 'f':
vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK) Commit 841a915d20c7b2 ("printf: Do not have bprintf dereference pointers") would preprocess various pointers that are dereferenced in the bprintf() because the recording and printing are done at two different times. Some pointers stayed dereferenced in the ring buffer because user space could handle them (namely "%pS" and friends). Pointers that are not dereferenced should not be processed immediately but instead just saved directly. Cc: stable@vger.kernel.org Fixes: 841a915d20c7b2 ("printf: Do not have bprintf dereference pointers") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-04 02:38:53 +08:00
case 'x':
case 'K':
printf: add support for printing symbolic error names It has been suggested several times to extend vsnprintf() to be able to convert the numeric value of ENOSPC to print "ENOSPC". This implements that as a %p extension: With %pe, one can do if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %pe\n", foo); return PTR_ERR(foo); } instead of what is seen in quite a few places in the kernel: if (IS_ERR(foo)) { pr_err("Sorry, can't do that: %ld\n", PTR_ERR(foo)); return PTR_ERR(foo); } If the value passed to %pe is an ERR_PTR, but the library function errname() added here doesn't know about the value, the value is simply printed in decimal. If the value passed to %pe is not an ERR_PTR, we treat it as an ordinary %p and thus print the hashed value (passing non-ERR_PTR values to %pe indicates a bug in the caller, but we can't do much about that). With my embedded hat on, and because it's not very invasive to do, I've made it possible to remove this. The errname() function and associated lookup tables take up about 3K. For most, that's probably quite acceptable and a price worth paying for more readable dmesg (once this starts getting used), while for those that disable printk() it's of very little use - I don't see a procfs/sysfs/seq_printf() file reasonably making use of this - and they clearly want to squeeze vmlinux as much as possible. Hence the default y if PRINTK. The symbols to include have been found by massaging the output of find arch include -iname 'errno*.h' | xargs grep -E 'define\s*E' In the cases where some common aliasing exists (e.g. EAGAIN=EWOULDBLOCK on all platforms, EDEADLOCK=EDEADLK on most), I've moved the more popular one (in terms of 'git grep -w Efoo | wc) to the bottom so that one takes precedence. Link: http://lkml.kernel.org/r/20191015190706.15989-1-linux@rasmusvillemoes.dk To: "Jonathan Corbet" <corbet@lwn.net> To: linux-kernel@vger.kernel.org Cc: "Andy Shevchenko" <andy.shevchenko@gmail.com> Cc: "Andrew Morton" <akpm@linux-foundation.org> Cc: "Joe Perches" <joe@perches.com> Cc: linux-doc@vger.kernel.org Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Uwe Kleine-König <uwe@kleine-koenig.org> Reviewed-by: Petr Mladek <pmladek@suse.com> [andy.shevchenko@gmail.com: use abs()] Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-16 03:07:05 +08:00
case 'e':
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
process = true;
break;
default:
if (!isalnum(*fmt)) {
process = true;
break;
}
/* Pointer dereference was already processed */
if (str < end) {
len = copy = strlen(args);
if (copy > end - str)
copy = end - str;
memcpy(str, args, copy);
str += len;
vsprintf: Fix off-by-one bug in bstr_printf() processing dereferenced pointers The functions vbin_printf() and bstr_printf() are used by trace_printk() to try to keep the overhead down during printing. trace_printk() uses vbin_printf() at the time of execution, as it only scans the fmt string to record the printf values into the buffer, and then uses vbin_printf() to do the conversions to print the string based on the format and the saved values in the buffer. This is an issue for dereferenced pointers, as before commit 841a915d20c7b, the processing of the pointer could happen some time after the pointer value was recorded (reading the trace buffer). This means the processing of the value at a later time could show different results, or even crash the system, if the pointer no longer existed. Commit 841a915d20c7b addressed this by processing dereferenced pointers at the time of execution and save the result in the ring buffer as a string. The bstr_printf() would then treat these pointers as normal strings, and print the value. But there was an off-by-one bug here, where after processing the argument, it move the pointer only "strlen(arg)" which made the arg pointer not point to the next argument in the ring buffer, but instead point to the nul character of the last argument. This causes any values after a dereferenced pointer to be corrupted. Cc: stable@vger.kernel.org Fixes: 841a915d20c7b ("vsprintf: Do not have bprintf dereference pointers") Reported-by: Nikolay Borisov <nborisov@suse.com> Tested-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-05 22:08:03 +08:00
args += len + 1;
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
}
}
if (process)
str = pointer(fmt, str, end, get_arg(void *), spec);
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
while (isalnum(*fmt))
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
fmt++;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
vsprintf: Do not have bprintf dereference pointers When trace_printk() was introduced, it was discussed that making it be as low overhead as possible, that the processing of the format string should be delayed until it is read. That is, a "trace_printk()" should not convert the %d into numbers and so on, but instead, save the fmt string and all the args in the buffer at the time of recording. When the trace_printk() data is read, it would then parse the format string and do the conversions of the saved arguments in the tracing buffer. The code to perform this was added to vsprintf where vbin_printf() would save the arguments of a specified format string in a buffer, then bstr_printf() could be used to convert the buffer with the same format string into the final output, as if vsprintf() was called in one go. The issue arises when dereferenced pointers are used. The problem is that something like %*pbl which reads a bitmask, will save the pointer to the bitmask in the buffer. Then the reading of the buffer via bstr_printf() will then look at the pointer to process the final output. Obviously the value of that pointer could have changed since the time it was recorded to the time the buffer is read. Worse yet, the bitmask could be unmapped, and the reading of the trace buffer could actually cause a kernel oops. Another problem is that user space tools such as perf and trace-cmd do not have access to the contents of these pointers, and they become useless when the tracing buffer is extracted. Instead of having vbin_printf() simply save the pointer in the buffer for later processing, have it perform the formatting at the time bin_printf() is called. This will fix the issue of dereferencing pointers at a later time, and has the extra benefit of having user space tools understand these values. Since perf and trace-cmd already can handle %p[sSfF] via saving kallsyms, their pointers are saved and not processed during vbin_printf(). If they were converted, it would break perf and trace-cmd, as they would not know how to deal with the conversion. Link: http://lkml.kernel.org/r/20171228204025.14a71d8f@gandalf.local.home Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-29 09:40:25 +08:00
}
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_PERCENT_CHAR:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (str < end)
*str = '%';
++str;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
break;
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
case FORMAT_TYPE_INVALID:
goto out;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
default: {
unsigned long long num;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
switch (spec.type) {
case FORMAT_TYPE_LONG_LONG:
num = get_arg(long long);
break;
case FORMAT_TYPE_ULONG:
case FORMAT_TYPE_LONG:
num = get_arg(unsigned long);
break;
case FORMAT_TYPE_SIZE_T:
num = get_arg(size_t);
break;
case FORMAT_TYPE_PTRDIFF:
num = get_arg(ptrdiff_t);
break;
printk: add support of hh length modifier for printk Impact: new feature, extend vsprintf format strings hh is used as length modifier for signed char or unsigned char. It is supported by glibc, we add kernel support now. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: torvalds@linux-foundation.org Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49CC9739.30107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-27 17:07:05 +08:00
case FORMAT_TYPE_UBYTE:
num = get_arg(unsigned char);
break;
case FORMAT_TYPE_BYTE:
num = get_arg(signed char);
break;
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
case FORMAT_TYPE_USHORT:
num = get_arg(unsigned short);
break;
case FORMAT_TYPE_SHORT:
num = get_arg(short);
break;
case FORMAT_TYPE_UINT:
num = get_arg(unsigned int);
break;
default:
num = get_arg(int);
}
str = number(str, end, num, spec);
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
} /* default: */
} /* switch(spec.type) */
} /* while(*fmt) */
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
lib/vsprintf.c: handle invalid format specifiers more robustly If we meet any invalid or unsupported format specifier, 'handling' it by just printing it as a literal string is not safe: Presumably the format string and the arguments passed gcc's type checking, but that means something like sprintf(buf, "%n %pd", &intvar, dentry) would end up interpreting &intvar as a struct dentry*. When the offending specifier was %n it used to be at the end of the format string, but we can't rely on that always being the case. Also, gcc doesn't complain about some more or less exotic qualifiers (or 'length modifiers' in posix-speak) such as 'j' or 'q', but being unrecognized by the kernel's printf implementation, they'd be interpreted as unknown specifiers, and the rest of arguments would be interpreted wrongly. So let's complain about anything we don't understand, not just %n, and stop pretending that we'd be able to make sense of the rest of the format/arguments. If the offending specifier is in a printk() call we unfortunately only get a "BUG: recent printk recursion!", but at least direct users of the sprintf family will be caught. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:30:20 +08:00
out:
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
if (size > 0) {
if (str < end)
*str = '\0';
else
end[-1] = '\0';
}
vsprintf: unify the format decoding layer for its 3 users An new optimization is making its way to ftrace. Its purpose is to make trace_printk() consuming less memory and be faster. Written by Lai Jiangshan, the approach is to delay the formatting job from tracing time to output time. Currently, a call to trace_printk() will format the whole string and insert it into the ring buffer. Then you can read it on /debug/tracing/trace file. The new implementation stores the address of the format string and the binary parameters into the ring buffer, making the packet more compact and faster to insert. Later, when the user exports the traces, the format string is retrieved with the binary parameters and the formatting job is eventually done. The new implementation rewrites a lot of format decoding bits from vsnprintf() function, making now 3 differents functions to maintain in their duplicated parts of printf format decoding bits. Suggested by Ingo Molnar, this patch tries to factorize the most possible common bits from these functions. The real common part between them is the format decoding. Although they do somewhat similar jobs, their way to export or import the parameters is very different. Thus, only the decoding layer is extracted, unless you see other parts that could be worth factorized. Changes in V2: - Address a suggestion from Linus to group the format_decode() parameters inside a structure. Changes in v3: - Address other cleanups suggested by Ingo and Linus such as passing the printf_spec struct to the format helpers: pointer()/number()/string() Note that this struct is passed by copy and not by address. This is to avoid side effects because these functions often change these values and the changes shoudn't be persistant when a callee helper returns. It would be too risky. - Various cleanups (code alignement, switch/case instead of if/else fountains). - Fix a bug that printed the first format specifier following a %p Changes in v4: - drop unapropriate const qualifier loss while casting fmt to a char * (thanks to Vegard Nossum for having pointed this out). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1236356510-8381-6-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:50 +08:00
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
#undef get_arg
/* the trailing null byte doesn't count towards the total */
return str - buf;
}
EXPORT_SYMBOL_GPL(bstr_printf);
/**
* bprintf - Parse a format string and place args' binary value in a buffer
* @bin_buf: The buffer to place args' binary value
* @size: The size of the buffer(by words(32bits), not characters)
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The function returns the number of words(u32) written
* into @bin_buf.
*/
int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
{
va_list args;
int ret;
va_start(args, fmt);
ret = vbin_printf(bin_buf, size, fmt, args);
va_end(args);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
vsprintf: add binary printf Impact: add new APIs for binary trace printk infrastructure vbin_printf(): write args to binary buffer, string is copied when "%s" is occurred. bstr_printf(): read from binary buffer for args and format a string [fweisbec@gmail.com: rebase] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <1236356510-8381-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-07 00:21:46 +08:00
return ret;
}
EXPORT_SYMBOL_GPL(bprintf);
#endif /* CONFIG_BINARY_PRINTF */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/**
* vsscanf - Unformat a buffer into a list of arguments
* @buf: input buffer
* @fmt: format of buffer
* @args: arguments
*/
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int vsscanf(const char *buf, const char *fmt, va_list args)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
const char *str = buf;
char *next;
char digit;
int num = 0;
vsprintf.c: Reduce sizeof struct printf_spec from 24 to 8 bytes Reducing the size of struct printf_spec is a good thing because multiple instances are commonly passed on stack. It's possible for type to be u8 and field_width to be s8, but this is likely small enough for now. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-07 09:10:14 +08:00
u8 qualifier;
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
unsigned int base;
union {
long long s;
unsigned long long u;
} val;
vsprintf.c: Reduce sizeof struct printf_spec from 24 to 8 bytes Reducing the size of struct printf_spec is a good thing because multiple instances are commonly passed on stack. It's possible for type to be u8 and field_width to be s8, but this is likely small enough for now. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-07 09:10:14 +08:00
s16 field_width;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
bool is_sign;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
lib/vsprintf.c: improve standard conformance of sscanf() Xen's pciback points out a couple of deficiencies with vsscanf()'s standard conformance: - Trailing character matching cannot be checked by the caller: With a format string of "(%x:%x.%x) %n" absence of the closing parenthesis cannot be checked, as input of "(00:00.0)" doesn't cause the %n to be evaluated (because of the code not skipping white space before the trailing %n). - The parameter corresponding to a trailing %n could get filled even if there was a matching error: With a format string of "(%x:%x.%x)%n", input of "(00:00.0]" would still fill the respective variable pointed to (and hence again make the mismatch non-detectable by the caller). This patch aims at fixing those, but leaves other non-conforming aspects of it untouched, among them these possibly relevant ones: - improper handling of the assignment suppression character '*' (blindly discarding all succeeding non-white space from the format and input strings), - not honoring conversion specifiers for %n, - not recognizing the C99 conversion specifier 't' (recognized by vsprintf()). Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:13:24 +08:00
while (*fmt) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* skip any white space in format */
/* white space in format matchs any amount of
* white space, including none, in the input.
*/
if (isspace(*fmt)) {
tree-wide: convert open calls to remove spaces to skip_spaces() lib function Makes use of skip_spaces() defined in lib/string.c for removing leading spaces from strings all over the tree. It decreases lib.a code size by 47 bytes and reuses the function tree-wide: text data bss dec hex filename 64688 584 592 65864 10148 (TOTALS-BEFORE) 64641 584 592 65817 10119 (TOTALS-AFTER) Also, while at it, if we see (*str && isspace(*str)), we can be sure to remove the first condition (*str) as the second one (isspace(*str)) also evaluates to 0 whenever *str == 0, making it redundant. In other words, "a char equals zero is never a space". Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below, and found occurrences of this pattern on 3 more files: drivers/leds/led-class.c drivers/leds/ledtrig-timer.c drivers/video/output.c @@ expression str; @@ ( // ignore skip_spaces cases while (*str && isspace(*str)) { \(str++;\|++str;\) } | - *str && isspace(*str) ) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Cc: Julia Lawall <julia@diku.dk> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Neil Brown <neilb@suse.de> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: David Howells <dhowells@redhat.com> Cc: <linux-ext4@vger.kernel.org> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:06 +08:00
fmt = skip_spaces(++fmt);
str = skip_spaces(str);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
/* anything that is not a conversion must match exactly */
if (*fmt != '%' && *fmt) {
if (*fmt++ != *str++)
break;
continue;
}
if (!*fmt)
break;
++fmt;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* skip this conversion.
* advance both strings to next white space
*/
if (*fmt == '*') {
lib/vsprintf.c: improve standard conformance of sscanf() Xen's pciback points out a couple of deficiencies with vsscanf()'s standard conformance: - Trailing character matching cannot be checked by the caller: With a format string of "(%x:%x.%x) %n" absence of the closing parenthesis cannot be checked, as input of "(00:00.0)" doesn't cause the %n to be evaluated (because of the code not skipping white space before the trailing %n). - The parameter corresponding to a trailing %n could get filled even if there was a matching error: With a format string of "(%x:%x.%x)%n", input of "(00:00.0]" would still fill the respective variable pointed to (and hence again make the mismatch non-detectable by the caller). This patch aims at fixing those, but leaves other non-conforming aspects of it untouched, among them these possibly relevant ones: - improper handling of the assignment suppression character '*' (blindly discarding all succeeding non-white space from the format and input strings), - not honoring conversion specifiers for %n, - not recognizing the C99 conversion specifier 't' (recognized by vsprintf()). Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:13:24 +08:00
if (!*str)
break;
sscanf: implement basic character sets Implement basic character sets for the '%[' conversion specifier. The '%[' conversion specifier matches a nonempty sequence of characters from the specified set of accepted (or with '^', rejected) characters between the brackets. The substring matched is to be made up of characters in (or not in) the set. This is useful for matching substrings that are delimited by something other than spaces. This implementation differs from its glibc counterpart in the following ways: (1) No support for character ranges (e.g., 'a-z' or '0-9') (2) The hyphen '-' is not a special character (3) The closing bracket ']' cannot be matched (4) No support (yet) for discarding matching input ('%*[') The bitmap code is largely based upon sample code which was provided by Rasmus. The motivation for adding character set support to sscanf originally stemmed from the kernel livepatching project. An ongoing patchset utilizes new livepatch Elf symbol and section names to store important metadata livepatch needs to properly apply its patches. Such metadata is stored in these section and symbol names as substrings delimited by periods '.' and commas ','. For example, a livepatch symbol name might look like this: .klp.sym.vmlinux.printk,0 However, sscanf currently can only extract "substrings" delimited by whitespace using the "%s" specifier. Thus for the above symbol name, one cannot not use sscanf() to extract substrings "vmlinux" or "printk", for example. A number of discussions on the livepatch mailing list dealing with string parsing code for extracting these '.' and ',' delimited substrings eventually led to the conclusion that such code would be completely unnecessary if the kernel sscanf() supported character sets. Thus only a single sscanf() call would be necessary to extract these substrings. In addition, such an addition to sscanf() could benefit other areas of the kernel that might have a similar need in the future. [akpm@linux-foundation.org: 80-col tweaks] Signed-off-by: Jessica Yu <jeyu@redhat.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-18 05:23:07 +08:00
while (!isspace(*fmt) && *fmt != '%' && *fmt) {
/* '%*[' not yet supported, invalid format */
if (*fmt == '[')
return num;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
fmt++;
sscanf: implement basic character sets Implement basic character sets for the '%[' conversion specifier. The '%[' conversion specifier matches a nonempty sequence of characters from the specified set of accepted (or with '^', rejected) characters between the brackets. The substring matched is to be made up of characters in (or not in) the set. This is useful for matching substrings that are delimited by something other than spaces. This implementation differs from its glibc counterpart in the following ways: (1) No support for character ranges (e.g., 'a-z' or '0-9') (2) The hyphen '-' is not a special character (3) The closing bracket ']' cannot be matched (4) No support (yet) for discarding matching input ('%*[') The bitmap code is largely based upon sample code which was provided by Rasmus. The motivation for adding character set support to sscanf originally stemmed from the kernel livepatching project. An ongoing patchset utilizes new livepatch Elf symbol and section names to store important metadata livepatch needs to properly apply its patches. Such metadata is stored in these section and symbol names as substrings delimited by periods '.' and commas ','. For example, a livepatch symbol name might look like this: .klp.sym.vmlinux.printk,0 However, sscanf currently can only extract "substrings" delimited by whitespace using the "%s" specifier. Thus for the above symbol name, one cannot not use sscanf() to extract substrings "vmlinux" or "printk", for example. A number of discussions on the livepatch mailing list dealing with string parsing code for extracting these '.' and ',' delimited substrings eventually led to the conclusion that such code would be completely unnecessary if the kernel sscanf() supported character sets. Thus only a single sscanf() call would be necessary to extract these substrings. In addition, such an addition to sscanf() could benefit other areas of the kernel that might have a similar need in the future. [akpm@linux-foundation.org: 80-col tweaks] Signed-off-by: Jessica Yu <jeyu@redhat.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-18 05:23:07 +08:00
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
while (!isspace(*str) && *str)
str++;
continue;
}
/* get field width */
field_width = -1;
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (isdigit(*fmt)) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
field_width = skip_atoi(&fmt);
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (field_width <= 0)
break;
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* get conversion qualifier */
qualifier = -1;
lib: make _tolower() public This function is required by *printf and kstrto* functions that are located in the different modules. This patch makes _tolower() public. However, it's good idea to not use the helper outside of mentioned functions. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 08:13:20 +08:00
if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
lib/vsprintf.c: remove %Z support Now that %z is standartised in C99 there is no reason to support %Z. Unlike %L it doesn't even make format strings smaller. Use BUILD_BUG_ON in a couple ATM drivers. In case anyone didn't notice lib/vsprintf.o is about half of SLUB which is in my opinion is quite an achievement. Hopefully this patch inspires someone else to trim vsprintf.c more. Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-28 06:30:02 +08:00
*fmt == 'z') {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
qualifier = *fmt++;
if (unlikely(qualifier == *fmt)) {
if (qualifier == 'h') {
qualifier = 'H';
fmt++;
} else if (qualifier == 'l') {
qualifier = 'L';
fmt++;
}
}
}
lib/vsprintf.c: improve standard conformance of sscanf() Xen's pciback points out a couple of deficiencies with vsscanf()'s standard conformance: - Trailing character matching cannot be checked by the caller: With a format string of "(%x:%x.%x) %n" absence of the closing parenthesis cannot be checked, as input of "(00:00.0)" doesn't cause the %n to be evaluated (because of the code not skipping white space before the trailing %n). - The parameter corresponding to a trailing %n could get filled even if there was a matching error: With a format string of "(%x:%x.%x)%n", input of "(00:00.0]" would still fill the respective variable pointed to (and hence again make the mismatch non-detectable by the caller). This patch aims at fixing those, but leaves other non-conforming aspects of it untouched, among them these possibly relevant ones: - improper handling of the assignment suppression character '*' (blindly discarding all succeeding non-white space from the format and input strings), - not honoring conversion specifiers for %n, - not recognizing the C99 conversion specifier 't' (recognized by vsprintf()). Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-05 08:13:24 +08:00
if (!*fmt)
break;
if (*fmt == 'n') {
/* return number of characters read so far */
*va_arg(args, int *) = str - buf;
++fmt;
continue;
}
if (!*str)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
break;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
base = 10;
lib/vsprintf.c: fix comparison to bool Fixing 2 coccinelle warnings: lib/vsprintf.c:2350:2-9: WARNING: Assignment of bool to 0/1 lib/vsprintf.c:2389:3-10: WARNING: Assignment of bool to 0/1 Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-05 07:11:52 +08:00
is_sign = false;
vsprintf: move local vars to block local vars and remove unneeded ones Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:59 +08:00
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
switch (*fmt++) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
case 'c':
{
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
char *s = (char *)va_arg(args, char*);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
if (field_width == -1)
field_width = 1;
do {
*s++ = *str++;
} while (--field_width > 0 && *str);
num++;
}
continue;
case 's':
{
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
char *s = (char *)va_arg(args, char *);
if (field_width == -1)
kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN - C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not USHORT_MAX/SHORT_MAX/SHORT_MIN. - Make SHRT_MIN of type s16, not int, for consistency. [akpm@linux-foundation.org: fix drivers/dma/timb_dma.c] [akpm@linux-foundation.org: fix security/keys/keyring.c] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 05:33:03 +08:00
field_width = SHRT_MAX;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* first, skip leading white space in buffer */
tree-wide: convert open calls to remove spaces to skip_spaces() lib function Makes use of skip_spaces() defined in lib/string.c for removing leading spaces from strings all over the tree. It decreases lib.a code size by 47 bytes and reuses the function tree-wide: text data bss dec hex filename 64688 584 592 65864 10148 (TOTALS-BEFORE) 64641 584 592 65817 10119 (TOTALS-AFTER) Also, while at it, if we see (*str && isspace(*str)), we can be sure to remove the first condition (*str) as the second one (isspace(*str)) also evaluates to 0 whenever *str == 0, making it redundant. In other words, "a char equals zero is never a space". Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below, and found occurrences of this pattern on 3 more files: drivers/leds/led-class.c drivers/leds/ledtrig-timer.c drivers/video/output.c @@ expression str; @@ ( // ignore skip_spaces cases while (*str && isspace(*str)) { \(str++;\|++str;\) } | - *str && isspace(*str) ) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Cc: Julia Lawall <julia@diku.dk> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Neil Brown <neilb@suse.de> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: David Howells <dhowells@redhat.com> Cc: <linux-ext4@vger.kernel.org> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:06 +08:00
str = skip_spaces(str);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* now copy until next white space */
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
while (*str && !isspace(*str) && field_width--)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
*s++ = *str++;
*s = '\0';
num++;
}
continue;
sscanf: implement basic character sets Implement basic character sets for the '%[' conversion specifier. The '%[' conversion specifier matches a nonempty sequence of characters from the specified set of accepted (or with '^', rejected) characters between the brackets. The substring matched is to be made up of characters in (or not in) the set. This is useful for matching substrings that are delimited by something other than spaces. This implementation differs from its glibc counterpart in the following ways: (1) No support for character ranges (e.g., 'a-z' or '0-9') (2) The hyphen '-' is not a special character (3) The closing bracket ']' cannot be matched (4) No support (yet) for discarding matching input ('%*[') The bitmap code is largely based upon sample code which was provided by Rasmus. The motivation for adding character set support to sscanf originally stemmed from the kernel livepatching project. An ongoing patchset utilizes new livepatch Elf symbol and section names to store important metadata livepatch needs to properly apply its patches. Such metadata is stored in these section and symbol names as substrings delimited by periods '.' and commas ','. For example, a livepatch symbol name might look like this: .klp.sym.vmlinux.printk,0 However, sscanf currently can only extract "substrings" delimited by whitespace using the "%s" specifier. Thus for the above symbol name, one cannot not use sscanf() to extract substrings "vmlinux" or "printk", for example. A number of discussions on the livepatch mailing list dealing with string parsing code for extracting these '.' and ',' delimited substrings eventually led to the conclusion that such code would be completely unnecessary if the kernel sscanf() supported character sets. Thus only a single sscanf() call would be necessary to extract these substrings. In addition, such an addition to sscanf() could benefit other areas of the kernel that might have a similar need in the future. [akpm@linux-foundation.org: 80-col tweaks] Signed-off-by: Jessica Yu <jeyu@redhat.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-18 05:23:07 +08:00
/*
* Warning: This implementation of the '[' conversion specifier
* deviates from its glibc counterpart in the following ways:
* (1) It does NOT support ranges i.e. '-' is NOT a special
* character
* (2) It cannot match the closing bracket ']' itself
* (3) A field width is required
* (4) '%*[' (discard matching input) is currently not supported
*
* Example usage:
* ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
* buf1, buf2, buf3);
* if (ret < 3)
* // etc..
*/
case '[':
{
char *s = (char *)va_arg(args, char *);
DECLARE_BITMAP(set, 256) = {0};
unsigned int len = 0;
bool negate = (*fmt == '^');
/* field width is required */
if (field_width == -1)
return num;
if (negate)
++fmt;
for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
set_bit((u8)*fmt, set);
/* no ']' or no character set found */
if (!*fmt || !len)
return num;
++fmt;
if (negate) {
bitmap_complement(set, set, 256);
/* exclude null '\0' byte */
clear_bit(0, set);
}
/* match must be non-empty */
if (!test_bit((u8)*str, set))
return num;
while (test_bit((u8)*str, set) && field_width--)
*s++ = *str++;
*s = '\0';
++num;
}
continue;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
case 'o':
base = 8;
break;
case 'x':
case 'X':
base = 16;
break;
case 'i':
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
base = 0;
lib/vsprintf: Mark expected switch fall-through In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Link: http://lkml.kernel.org/r/20180216210711.79901-9-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:11 +08:00
/* fall through */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
case 'd':
lib/vsprintf.c: fix comparison to bool Fixing 2 coccinelle warnings: lib/vsprintf.c:2350:2-9: WARNING: Assignment of bool to 0/1 lib/vsprintf.c:2389:3-10: WARNING: Assignment of bool to 0/1 Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-05 07:11:52 +08:00
is_sign = true;
lib/vsprintf: Mark expected switch fall-through In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Link: http://lkml.kernel.org/r/20180216210711.79901-9-andriy.shevchenko@linux.intel.com To: "Tobin C . Harding" <me@tobin.cc> To: linux@rasmusvillemoes.dk To: Joe Perches <joe@perches.com> To: linux-kernel@vger.kernel.org To: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-02-17 05:07:11 +08:00
/* fall through */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
case 'u':
break;
case '%':
/* looking for '%' in str */
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
if (*str++ != '%')
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return num;
continue;
default:
/* invalid format; stop here */
return num;
}
/* have some sort of integer conversion.
* first, skip white space in buffer.
*/
tree-wide: convert open calls to remove spaces to skip_spaces() lib function Makes use of skip_spaces() defined in lib/string.c for removing leading spaces from strings all over the tree. It decreases lib.a code size by 47 bytes and reuses the function tree-wide: text data bss dec hex filename 64688 584 592 65864 10148 (TOTALS-BEFORE) 64641 584 592 65817 10119 (TOTALS-AFTER) Also, while at it, if we see (*str && isspace(*str)), we can be sure to remove the first condition (*str) as the second one (isspace(*str)) also evaluates to 0 whenever *str == 0, making it redundant. In other words, "a char equals zero is never a space". Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below, and found occurrences of this pattern on 3 more files: drivers/leds/led-class.c drivers/leds/ledtrig-timer.c drivers/video/output.c @@ expression str; @@ ( // ignore skip_spaces cases while (*str && isspace(*str)) { \(str++;\|++str;\) } | - *str && isspace(*str) ) Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Cc: Julia Lawall <julia@diku.dk> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Neil Brown <neilb@suse.de> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: David Howells <dhowells@redhat.com> Cc: <linux-ext4@vger.kernel.org> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:01:06 +08:00
str = skip_spaces(str);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
digit = *str;
if (is_sign && digit == '-')
digit = *(str + 1);
if (!digit
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
|| (base == 16 && !isxdigit(digit))
|| (base == 10 && !isdigit(digit))
|| (base == 8 && (!isdigit(digit) || digit > '7'))
|| (base == 0 && !isdigit(digit)))
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (is_sign)
val.s = qualifier != 'L' ?
simple_strtol(str, &next, base) :
simple_strtoll(str, &next, base);
else
val.u = qualifier != 'L' ?
simple_strtoul(str, &next, base) :
simple_strtoull(str, &next, base);
if (field_width > 0 && next - str > field_width) {
if (base == 0)
_parse_integer_fixup_radix(str, &base);
while (next - str > field_width) {
if (is_sign)
val.s = div_s64(val.s, base);
else
val.u = div_u64(val.u, base);
--next;
}
}
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
switch (qualifier) {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
case 'H': /* that's 'hh' in format */
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (is_sign)
*va_arg(args, signed char *) = val.s;
else
*va_arg(args, unsigned char *) = val.u;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
break;
case 'h':
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (is_sign)
*va_arg(args, short *) = val.s;
else
*va_arg(args, unsigned short *) = val.u;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
break;
case 'l':
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (is_sign)
*va_arg(args, long *) = val.s;
else
*va_arg(args, unsigned long *) = val.u;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
break;
case 'L':
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (is_sign)
*va_arg(args, long long *) = val.s;
else
*va_arg(args, unsigned long long *) = val.u;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
break;
case 'z':
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
*va_arg(args, size_t *) = val.u;
break;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
default:
sscanf: don't ignore field widths for numeric conversions This is another step towards better standard conformance. Rather than adding a local buffer to store the specified portion of the string (with the need to enforce an arbitrary maximum supported width to limit the buffer size), do a maximum width conversion and then drop as much of it as is necessary to meet the caller's request. Also fail on negative field widths. Uses the deprecated simple_strto*() functions because kstrtoXX() fail on non-zero terminated strings. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-18 08:01:31 +08:00
if (is_sign)
*va_arg(args, int *) = val.s;
else
*va_arg(args, unsigned int *) = val.u;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
break;
}
num++;
if (!next)
break;
str = next;
}
fix sscanf %n match at end of input string I was playing with some code that sometimes got a string where a %n match should have been done where the input string ended, for example like this: sscanf("abc123", "abc%d%n", &a, &n); /* doesn't work */ sscanf("abc123a", "abc%d%n", &a, &n); /* works */ However, the scanf function in the kernel doesn't convert the %n in that case because it has already matched the complete input after %d and just completely stops matching then. This patch fixes that. [akpm@linux-foundation.org: cleanups] Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 15:27:20 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return num;
}
EXPORT_SYMBOL(vsscanf);
/**
* sscanf - Unformat a buffer into a list of arguments
* @buf: input buffer
* @fmt: formatting of buffer
* @...: resulting arguments
*/
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
int sscanf(const char *buf, const char *fmt, ...)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
va_list args;
int i;
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
va_start(args, fmt);
i = vsscanf(buf, fmt, args);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
va_end(args);
vsprintf: give it some care to please checkpatch.pl Most relevant complaints were addressed. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 10:00:57 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return i;
}
EXPORT_SYMBOL(sscanf);