Commit Graph

751994 Commits

Author SHA1 Message Date
Joe Perches 5d43090261 checkpatch: whinge about bool bitfields
Using bool in a bitfield isn't a good idea as the alignment behavior is
arch implementation defined.

Suggest using unsigned int or u<8|16|32> instead.

Link: http://lkml.kernel.org/r/e22fb871b1b7f2fda4b22f3a24e0d7f092eb612c.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Heinrich Schuchardt 38dca988bb checkpatch: allow space between colon and bracket
Allow a space between a colon and subsequent opening bracket.  This
sequence may occur in inline assembler statements like

	asm(
		"ldr %[out], [%[in]]\n\t"
		: [out] "=r" (ret)
		: [in] "r" (addr)
	);

Link: http://lkml.kernel.org/r/20180403191655.23700-1-xypron.glpk@gmx.de
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Joe Perches 6a487211ec checkpatch: add test for assignment at start of line
Kernel style seems to prefer line wrapping an assignment with the
assignment operator on the previous line like:

	<leading tabs>	identifier =
				expression;
over
	<leading tabs>	identifier
				= expression;

somewhere around a 50:1 ratio

$ git grep -P "[^=]=\s*$" -- "*.[ch]" | wc -l
52008
$ git grep -P "^\s+[\*\/\+\|\%\-]?=[^=>]" | wc -l
1161

So add a --strict test for that condition.

Link: http://lkml.kernel.org/r/1522275726.2210.12.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Joe Perches bc22d9a7d3 checkpatch: test SYMBOLIC_PERMS multiple times per line
There are occasions where symbolic perms are used in a ternary like

		return (channel == 0) ? S_IRUGO | S_IWUSR : S_IRUGO;

The current test will find the first use "S_IRUGO | S_IWUSR" but not the
second use "S_IRUGO" on the same line.

Improve the test to look for all instances on a line.

Link: http://lkml.kernel.org/r/1522127944.12357.49.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Claudio Fontana 8d2e11b22d checkpatch: two spelling fixes
completly -> completely
wacking -> whacking

Link: http://lkml.kernel.org/r/1520405394-5586-1-git-send-email-claudio.fontana@gliwa.com
Signed-off-by: Claudio Fontana <claudio.fontana@gliwa.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Joe Perches 478b179980 checkpatch: improve get_quoted_string for TRACE_EVENT macros
The get_quoted_string function does not expect invalid arguments.

The $stat test can return non-statements for complicated macros like
TRACE_EVENT.

Allow the $stat block and test for vsprintf misuses to exceed the actual
block length and possibly test invalid lines by validating the arguments
of get_quoted_string.

Return "" if either get_quoted_string argument is undefined.

Miscellanea:

o Properly align the comment for the vsprintf extension test

Link: http://lkml.kernel.org/r/9e9725342ca3dfc0f5e3e0b8ca3c482b0e5712cc.1520356392.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Tobin C. Harding e3c6bc9566 checkpatch: warn for use of %px
Usage of the new %px specifier potentially leaks sensitive information.
Printing kernel addresses exposes the kernel layout in memory, this is
potentially exploitable.  We have tools in the kernel to help us do the
right thing.  We can have checkpatch warn developers of potential
dangers of using %px.

Have checkpatch emit a warning for usage of specifier %px.

Link: http://lkml.kernel.org/r/1519700648-23108-5-git-send-email-me@tobin.cc
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Tobin C. Harding e3d95a2a05 checkpatch: add sub routine get_stat_here()
checkpatch currently contains duplicate code.  We can define a sub
routine and call that instead.  This reduces code duplication and line
count.

Add subroutine get_stat_here().

Link: http://lkml.kernel.org/r/1519700648-23108-4-git-send-email-me@tobin.cc
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Tobin C. Harding c2066ca350 checkpatch: remove unused variable declarations
Variables are declared and not used, we should remove them.

Link: http://lkml.kernel.org/r/1519700648-23108-3-git-send-email-me@tobin.cc
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:36 -07:00
Tobin C. Harding 2a9f9d851c checkpatch: add sub routine get_stat_real()
checkpatch currently contains duplicate code.  We can define a sub
routine and call that instead.  This reduces code duplication and line
count.

Add subroutine get_stat_real()

Link: http://lkml.kernel.org/r/1519700648-23108-2-git-send-email-me@tobin.cc
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Gilad Ben-Yossef 3d102fc0e7 checkpatch: add Crypto ON_STACK to declaration_macros
Add the crypto API *_ON_STACK to $declaration_macros.

Resolves the following false warning:

WARNING: Missing a blank line after declarations
+			int err;
+			SHASH_DESC_ON_STACK(desc, ctx_p->shash_tfm);

Link: http://lkml.kernel.org/r/1518941636-4484-1-git-send-email-gilad@benyossef.com
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Rob Herring 9f3a89926d checkpatch.pl: add SPDX license tag check
Add SPDX license tag check based on the rules defined in
Documentation/process/license-rules.rst.  To summarize, SPDX license
tags should be on the 1st line (or 2nd line in scripts) using the
appropriate comment style for the file type.

Link: http://lkml.kernel.org/r/20180202154026.15298-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Igor Stoppa <igor.stoppa@huawei.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>
2018-04-11 10:28:35 -07:00
Joe Perches 85e12066ea checkpatch: improve parse_email signature checking
Bare email addresses with non alphanumeric characters require escape
quoting before being substituted in the parse_email routine.

e.g. Reported-by: syzbot+bbd8e9a06452cc48059b@syzkaller.appspotmail.com

Do so.

Link: http://lkml.kernel.org/r/1518631805.3678.12.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Matthew Wilcox 68c1f08203 lib/list_debug.c: print unmangled addresses
The entire point of printing the pointers in list_debug is to see if
there's any useful information in them (eg poison values, ASCII, etc);
obscuring them to see if they compare equal makes them much less useful.
If an attacker can force this message to be printed, we've already lost.

Link: http://lkml.kernel.org/r/20180401223237.GV13332@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Tobin C. Harding <me@tobin.cc>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Biggers <ebiggers3@gmail.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>
2018-04-11 10:28:35 -07:00
Colin Ian King 3175060092 lib/test_ubsan.c: make test_ubsan_misaligned_access() static
test_ubsan_misaligned_access() is local to the source and does not need
to be in global scope, so make it static.

Cleans up sparse warning:

  lib/test_ubsan.c:91:6: warning: symbol 'test_ubsan_misaligned_access' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20180313103048.28513-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Jinbum Park <jinb.park7@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.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>
2018-04-11 10:28:35 -07:00
Jinbum Park 854686f4ed lib: add testing module for UBSAN
This is a test module for UBSAN.  It triggers all undefined behaviors
that linux supports now, and detect them.

All test-cases have passed by compiling with gcc-5.5.0.

If use gcc-4.9.x, misaligned, out-of-bounds, object-size-mismatch will not
be detected.  Because gcc-4.9.x doesn't support them.

Link: http://lkml.kernel.org/r/20180309102247.GA2944@pjb1027-Latitude-E5410
Signed-off-by: Jinbum Park <jinb.park7@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.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>
2018-04-11 10:28:35 -07:00
Kees Cook f6f66c1bf5 lib/test_bitmap.c: do not accidentally use stack VLA
This avoids an accidental stack VLA (since the compiler thinks the value
of "len" can change, even when marked "const").  This just replaces it
with a #define so it will DTRT.

Seen with -Wvla.  Fixed as part of the directive to remove all VLAs from
the kernel: https://lkml.org/lkml/2018/3/7/621

Link: http://lkml.kernel.org/r/20180307212555.GA17927@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Randy Dunlap 5f00ae0d3e lib/Kconfig.debug: Debug Lockups and Hangs: keep SOFTLOCKUP options together
Keep all of the SOFTLOCKUP kconfig symbols together (instead of
injecting the HARDLOCKUP symbols in the midst of them) so that the
config tools display them with their dependencies.

Tested with 'make {menuconfig/nconfig/gconfig/xconfig}'.

Link: http://lkml.kernel.org/r/6be2d9ed-4656-5b94-460d-7f051e2c7570@infradead.org
Fixes: 05a4a95279 ("kernel/watchdog: split up config options")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Alexandre Bounine d387a31d75 MAINTAINERS: update email address for Alexandre Bounine
Link: http://lkml.kernel.org/r/1522958149-6157-1-git-send-email-alex.bou9@gmail.com
Signed-off-by: Alexandre Bounine <alex.bou9@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Barry Wood <barry.wood@idt.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Kees Cook 2cfe0d3009 task_struct: only use anon struct under randstruct plugin
The original intent for always adding the anonymous struct in
task_struct was to make sure we had compiler coverage.

However, this caused pathological padding of 40 bytes at the start of
task_struct.  Instead, move the anonymous struct to being only used when
struct layout randomization is enabled.

Link: http://lkml.kernel.org/r/20180327213609.GA2964@beast
Fixes: 29e48ce87f ("task_struct: Allow randomized")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Miguel Ojeda d4ef8d3ff0 clang-format: add configuration file
clang-format is a tool to format C/C++/...  code according to a set of
rules and heuristics.  Like most tools, it is not perfect nor covers
every single case, but it is good enough to be helpful.

In particular, it is useful for quickly re-formatting blocks of code
automatically, for reviewing full files in order to spot coding style
mistakes, typos and possible improvements.  It is also handy for sorting
``#includes``, for aligning variables and macros, for reflowing text and
other similar tasks.  It also serves as a teaching tool/guide for
newcomers.

The tool itself has been already included in the repositories of popular
Linux distributions for a long time.  The rules in this file are
intended for clang-format >= 4, which is easily available in most
distributions.

This commit adds the configuration file that contains the rules that the
tool uses to know how to format the code according to the kernel coding
style.  This gives us several advantages:

  * clang-format works out of the box with reasonable defaults;
    avoiding that everyone has to re-do the configuration.

  * Everyone agrees (eventually) on what is the most useful default
    configuration for most of the kernel.

  * If it becomes commonplace among kernel developers, clang-format
    may feel compelled to support us better. They already recognize
    the Linux kernel and its style in their documentation and in one
    of the style sub-options.

Some of clang-format's features relevant for the kernel are:

  * Uses clang's tooling support behind the scenes to parse and rewrite
    the code. It is not based on ad-hoc regexps.

  * Supports reasonably well the Linux kernel coding style.

  * Fast enough to be used at the press of a key.

  * There are already integrations (either built-in or third-party)
    for many common editors used by kernel developers (e.g. vim,
    emacs, Sublime, Atom...) that allow you to format an entire file
    or, more usefully, just your selection.

  * Able to parse unified diffs -- you can, for instance, reformat
    only the lines changed by a git commit.

  * Able to reflow text comments as well.

  * Widely supported and used by hundreds of developers in highly
    complex projects and organizations (e.g. the LLVM project itself,
    Chromium, WebKit, Google, Mozilla...). Therefore, it will be
    supported for a long time.

See more information about the tool at:

    https://clang.llvm.org/docs/ClangFormat.html
    https://clang.llvm.org/docs/ClangFormatStyleOptions.html

Link: http://lkml.kernel.org/r/20180318171632.qfkemw3mwbcukth6@gmail.com
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.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>
2018-04-11 10:28:35 -07:00
Alexey Dobriyan 3ea056c504 uts: create "struct uts_namespace" from kmem_cache
So "struct uts_namespace" can enjoy fine-grained SLAB debugging and
usercopy protection.

I'd prefer shorter name "utsns" but there is "user_namespace" already.

Link: http://lkml.kernel.org/r/20180228215158.GA23146@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Kees Cook bc4f2f5469 taint: add taint for randstruct
Since the randstruct plugin can intentionally produce extremely unusual
kernel structure layouts (even performance pathological ones), some
maintainers want to be able to trivially determine if an Oops is coming
from a randstruct-built kernel, so as to keep their sanity when
debugging.  This adds the new flag and initializes taint_mask
immediately when built with randstruct.

Link: http://lkml.kernel.org/r/1519084390-43867-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Kees Cook 9c4560e5bb taint: consolidate documentation
This consolidates the taint bit documentation into a single place with
both numeric and letter values.  Additionally adds the missing TAINT_AUX
documentation.

Link: http://lkml.kernel.org/r/1519084390-43867-3-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Kees Cook 47d4b263a2 taint: convert to indexed initialization
This converts to using indexed initializers instead of comments, adds a
comment on why the taint flags can't be an enum, and make sure that no
one forgets to update the taint_flags when adding new bits.

Link: http://lkml.kernel.org/r/1519084390-43867-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 1f5bd05476 proc: selftests: test /proc/uptime
The only tests I could come up with for /proc/uptime are:
 - test that values increase monotonically for 1 second,
 - bounce around CPUs and test the same thing.

Avoid glibc like plague for affinity given patches like this:
https://marc.info/?l=linux-kernel&m=152130031912594&w=4

Link: http://lkml.kernel.org/r/20180317165235.GB3445@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 4f1134370a proc: use slower rb_first()
In a typical for /proc "open+read+close" usecase, dentry is looked up
successfully on open only to be killed in dput() on close.  In fact
dentries which aren't /proc/*/...  and /proc/sys/* were almost NEVER
CACHED.  Simple printk in proc_lookup_de() shows that.

Now that ->delete hook intelligently picks which dentries should live in
dcache and which should not, rbtree caching is not necessary as dcache
does it job, at last!

As a side effect, struct proc_dir_entry shrinks by one pointer which can
go into inline name.

Link: http://lkml.kernel.org/r/20180314231032.GA15854@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
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>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 05c3f29283 proc: selftests: shotgun testing of read/readdir/readlink/write
Perform reads with nearly everything in /proc, and some writing as well.

Hopefully memleak checkers and KASAN will find something.

[adobriyan@gmail.com: /proc/kmsg can and will block if read under root]
  Link: http://lkml.kernel.org/r/20180316232147.GA20146@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
[adobriyan@gmail.com: /proc/sysrq-trigger lives on the ground floor]
  Link: http://lkml.kernel.org/r/20180317164911.GA3445@avx2
Link: http://lkml.kernel.org/r/20180315201251.GA12396@avx2
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>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 9cdd83e310 proc: switch struct proc_dir_entry::count to refcount
->count is honest reference count unlike ->in_use.

Link: http://lkml.kernel.org/r/20180313174550.GA4332@avx2
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>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan b77d70db65 proc: reject "." and ".." as filenames
Various subsystems can create files and directories in /proc with names
directly controlled by userspace.

Which means "/", "." and ".." are no-no.

"/" split is already taken care of, do the other 2 prohibited names.

Link: http://lkml.kernel.org/r/20180310001223.GB12443@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
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>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 5de3d401b7 proc: add selftest for last field of /proc/loadavg
Test fork counter formerly known as ->last_pid, the only part of
/proc/loadavg which can be tested.

Testing in init pid namespace is not reliable because of background
activity.

Link: http://lkml.kernel.org/r/20180311152241.GA26247@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan fe079a5e10 proc: do mmput ASAP for /proc/*/map_files
mm_struct is not needed while printing as all the data was already
extracted.

Link: http://lkml.kernel.org/r/20180309223120.GC3843@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 58c501aab3 proc: faster /proc/cmdline
Use seq_puts() and skip format string processing.

Link: http://lkml.kernel.org/r/20180309222948.GB3843@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 1539d584e4 proc: register filesystem last
As soon as register_filesystem() exits, filesystem can be mounted.  It
is better to present fully operational /proc.

Of course it doesn't matter because /proc is not modular but do it
anyway.

Drop error check, it should be handled by panicking.

Link: http://lkml.kernel.org/r/20180309222709.GA3843@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 35318db566 proc: fix /proc/*/map_files lookup some more
I totally forgot that _parse_integer() accepts arbitrary amount of
leading zeroes leading to the following lookups:

		OK
	# readlink /proc/1/map_files/56427ecba000-56427eddc000
	/lib/systemd/systemd

		bogus
	# readlink /proc/1/map_files/00000000000056427ecba000-56427eddc000
	/lib/systemd/systemd
	# readlink /proc/1/map_files/56427ecba000-00000000000056427eddc000
	/lib/systemd/systemd

Link: http://lkml.kernel.org/r/20180303215130.GA23480@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan b4884f2333 proc: move "struct proc_dir_entry" into kmem cache
"struct proc_dir_entry" is variable sized because of 0-length trailing
array for name, however, because of SLAB padding allocations it is
possible to make "struct proc_dir_entry" fixed sized and allocate same
amount of memory.

It buys fine-grained debugging with poisoning and usercopy protection
which is not possible with kmalloc-* caches.

Currently, on 32-bit 91+ byte allocations go into kmalloc-128 and on
64-bit 147+ byte allocations go to kmalloc-192 anyway.

Additional memory is allocated only for 38/46+ byte long names which are
rare or may not even exist in the wild.

Link: http://lkml.kernel.org/r/20180223205504.GA17139@avx2
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>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan c4219edf1d proc: test /proc/self/syscall
Read from /proc/self/syscall should yield read system call and correct
args in the output as current is reading /proc/self/syscall.

Link: http://lkml.kernel.org/r/20180226212145.GB742@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Alexey Dobriyan 9cd6565558 proc: test /proc/self/wchan
This patch starts testing /proc.  Many more tests to come (I promise).

Read from /proc/self/wchan should always return "0" as current is in
TASK_RUNNING state while reading /proc/self/wchan.

Link: http://lkml.kernel.org/r/20180226212006.GA742@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Danilo Krummrich 835b94e05c fs/proc/proc_sysctl.c: remove redundant link check in proc_sys_link_fill_cache()
proc_sys_link_fill_cache() does not need to check whether we're called
for a link - it's already done by scan().

Link: http://lkml.kernel.org/r/20180228013506.4915-2-danilokrummrich@dk-develop.de
Signed-off-by: Danilo Krummrich <danilokrummrich@dk-develop.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Luis R . Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Danilo Krummrich a0b0d1c345 fs/proc/proc_sysctl.c: fix potential page fault while unregistering sysctl table
proc_sys_link_fill_cache() does not take currently unregistering sysctl
tables into account, which might result into a page fault in
sysctl_follow_link() - add a check to fix it.

This bug has been present since v3.4.

Link: http://lkml.kernel.org/r/20180228013506.4915-1-danilokrummrich@dk-develop.de
Fixes: 0e47c99d7f ("sysctl: Replace root_list with links between sysctl_table_sets")
Signed-off-by: Danilo Krummrich <danilokrummrich@dk-develop.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Luis R . Rodriguez" <mcgrof@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.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>
2018-04-11 10:28:33 -07:00
Alexey Dobriyan 21dae0ad07 proc: use set_puts() at /proc/*/wchan
Link: http://lkml.kernel.org/r/20180217072011.GB16074@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Alexey Dobriyan 24b2ec2119 proc: check permissions earlier for /proc/*/wchan
get_wchan() accesses stack page before permissions are checked, let's
not play this game.

Link: http://lkml.kernel.org/r/20180217071923.GA16074@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Andrei Vagin d0f0223122 proc: replace seq_printf by seq_put_smth to speed up /proc/pid/status
seq_printf() works slower than seq_puts, seq_puts, etc.

== test_proc.c
int main(int argc, char **argv)
{
	int n, i, fd;
	char buf[16384];

	n = atoi(argv[1]);
	for (i = 0; i < n; i++) {
		fd = open(argv[2], O_RDONLY);
		if (fd < 0)
			return 1;
		if (read(fd, buf, sizeof(buf)) <= 0)
			return 1;
		close(fd);
	}

	return 0;
}
==

$ time ./test_proc  1000000 /proc/1/status

== Before path ==
real	0m5.171s
user	0m0.328s
sys	0m4.783s

== After patch ==
real	0m4.761s
user	0m0.334s
sys	0m4.366s

Link: http://lkml.kernel.org/r/20180212074931.7227-4-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 10:28:33 -07:00
Andrei Vagin 48dffbf82d proc: optimize single-symbol delimiters to spead up seq_put_decimal_ull
A delimiter is a string which is printed before a number.  A
syngle-symbol delimiters can be printed by set_putc() and this works
faster than printing by set_puts().

== test_proc.c

int main(int argc, char **argv)
{
	int n, i, fd;
	char buf[16384];

	n = atoi(argv[1]);
	for (i = 0; i < n; i++) {
		fd = open(argv[2], O_RDONLY);
		if (fd < 0)
			return 1;
		if (read(fd, buf, sizeof(buf)) <= 0)
			return 1;
		close(fd);
	}

	return 0;
}
==

$ time ./test_proc  1000000 /proc/1/stat

== Before patch ==
  real	0m3.820s
  user	0m0.337s
  sys	0m3.394s

== After patch ==
  real	0m3.110s
  user	0m0.324s
  sys	0m2.700s

Link: http://lkml.kernel.org/r/20180212074931.7227-3-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 10:28:33 -07:00
Andrei Vagin f66406638f proc: replace seq_printf on seq_putc to speed up /proc/pid/smaps
seq_putc() works much faster than seq_printf()

== Before patch ==
  $ time python test_smaps.py
  real    0m3.828s
  user    0m0.413s
  sys     0m3.408s

== After patch ==
  $ time python test_smaps.py
  real	0m3.405s
  user	0m0.401s
  sys	0m3.003s

== Before 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_aligned
      + 19.78% __walk_page_range
      + 12.74% seq_printf
      + 11.08% show_map_vma.isra.23
      + 1.68% seq_puts

== After patch ==
-   69.16%     5.70%  python   [kernel.kallsyms]    [k] show_smap.isra.33
   - 63.46% show_smap.isra.33
      + 25.98% seq_put_decimal_ull_aligned
      + 20.90% __walk_page_range
      + 12.60% show_map_vma.isra.23
        1.56% seq_putc
      + 1.55% seq_puts

Link: http://lkml.kernel.org/r/20180212074931.7227-2-avagin@openvz.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Reviewed-by: 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 10:28:33 -07:00
Andrei Vagin d1be35cb6f 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 10:28:33 -07:00
Alexey Dobriyan 2acddbe816 proc: account "struct pde_opener"
The allocation is persistent in fact as any fool can open a file in
/proc and sit on it.

Link: http://lkml.kernel.org/r/20180214082409.GC17157@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Alexey Dobriyan 195b8cf068 proc: move "struct pde_opener" to kmem cache
"struct pde_opener" is fixed size and we can have more granular approach
to debugging.

For those who don't know, per cache SLUB poisoning and red zoning don't
work if there is at least one object allocated which is hopeless in case
of kmalloc-64 but not in case of standalone cache.  Although systemd
opens 2 files from the get go, so it is hopeless after all.

Link: http://lkml.kernel.org/r/20180214082306.GB17157@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Alexey Dobriyan a9fabc3df4 proc: randomize "struct pde_opener"
The more the merrier.

Link: http://lkml.kernel.org/r/20180214081935.GA17157@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Alexey Dobriyan e7a6e291e3 proc: faster open/close of files without ->release hook
The whole point of code in fs/proc/inode.c is to make sure ->release
hook is called either at close() or at rmmod time.

All if it is unnecessary if there is no ->release hook.

Save allocation+list manipulations under spinlock in that case.

Link: http://lkml.kernel.org/r/20180214063033.GA15579@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00