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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
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
/*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* Added support for a Unix98-style ptmx device.
* -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
*
*/
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
#include <linux/module.h>
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/errno.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/fcntl.h>
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-09 01:51:30 +08:00
#include <linux/sched/signal.h>
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/string.h>
#include <linux/major.h>
#include <linux/mm.h>
#include <linux/init.h>
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
#include <linux/device.h>
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
#include <linux/uaccess.h>
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/bitops.h>
#include <linux/devpts_fs.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
#include <linux/mutex.h>
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
#include <linux/poll.h>
tty: add TIOCGPTPEER ioctl When opening the slave end of a PTY, it is not possible for userspace to safely ensure that /dev/pts/$num is actually a slave (in cases where the mount namespace in which devpts was mounted is controlled by an untrusted process). In addition, there are several unresolvable race conditions if userspace were to attempt to detect attacks through stat(2) and other similar methods [in addition it is not clear how userspace could detect attacks involving FUSE]. Resolve this by providing an interface for userpace to safely open the "peer" end of a PTY file descriptor by using the dentry cached by devpts. Since it is not possible to have an open master PTY without having its slave exposed in /dev/pts this interface is safe. This interface currently does not provide a way to get the master pty (since it is not clear whether such an interface is safe or even useful). Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Valentin Rothberg <vrothberg@suse.com> Signed-off-by: Aleksa Sarai <asarai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:15 +08:00
#include <linux/mount.h>
#include <linux/file.h>
#include <linux/ioctl.h>
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
#include <linux/compat.h>
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
pty: Add debug message for ptmx open Opens of /dev/ptmx don't use tty_open() so debug messages are not printed for those opens; print a debug message with the open count (which must always be 1) if TTY_DEBUG_HANGUP is defined. NB: Each tty core source file undefs support for debug messages. The relevant source file must be patched/edited to enable these messages. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-13 10:49:13 +08:00
#undef TTY_DEBUG_HANGUP
#ifdef TTY_DEBUG_HANGUP
# define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args)
#else
# define tty_debug_hangup(tty, f, args...) do {} while (0)
#endif
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +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
#ifdef CONFIG_UNIX98_PTYS
Make various things static Building an allnoconfig kernel, sparse asked whether these could be static, so I checked, and they are only used in the file where they are declared. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-08 10:09:15 +08:00
static struct tty_driver *ptm_driver;
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
static struct tty_driver *pts_driver;
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
static DEFINE_MUTEX(devpts_mutex);
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
#endif
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
static void pty_close(struct tty_struct *tty, struct file *filp)
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
{
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
BUG_ON(!tty);
if (tty->driver->subtype == PTY_TYPE_MASTER)
WARN_ON(tty->count > 1);
else {
tty: Replace TTY_IO_ERROR bit tests with tty_io_error() Abstract TTY_IO_ERROR status test treewide with tty_io_error(). NB: tty->flags uses atomic bit ops; replace non-atomic bit test with test_bit(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-10 08:06:48 +08:00
if (tty_io_error(tty))
pty: Ignore slave pty close() if never successfully opened If the master and slave ptys are opened in parallel, the slave open fails because the pty is still locked. This is as designed. However, pty_close() is still called for the slave pty which sets TTY_OTHER_CLOSED in the master pty. This can cause the master open to fail as well. Use a common pattern in other tty drivers by setting TTY_IO_ERROR until the open is successful and only closing the pty if not set. Note: the master pty always closes regardless of whether the open was successful, so that proper cleanup can occur. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-31 01:43:50 +08:00
return;
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 (tty->count > 2)
return;
}
pty: Ignore slave pty close() if never successfully opened If the master and slave ptys are opened in parallel, the slave open fails because the pty is still locked. This is as designed. However, pty_close() is still called for the slave pty which sets TTY_OTHER_CLOSED in the master pty. This can cause the master open to fail as well. Use a common pattern in other tty drivers by setting TTY_IO_ERROR until the open is successful and only closing the pty if not set. Note: the master pty always closes regardless of whether the open was successful, so that proper cleanup can occur. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-31 01:43:50 +08:00
set_bit(TTY_IO_ERROR, &tty->flags);
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
wake_up_interruptible(&tty->read_wait);
wake_up_interruptible(&tty->write_wait);
pty: Hold ctrl_lock for packet mode updates Updates to the packet mode enable require holding the ctrl_lock; the serialization prevents corruption of adjacent fields. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:28 +08:00
spin_lock_irq(&tty->ctrl_lock);
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
tty->packet = 0;
pty: Hold ctrl_lock for packet mode updates Updates to the packet mode enable require holding the ctrl_lock; the serialization prevents corruption of adjacent fields. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:28 +08:00
spin_unlock_irq(&tty->ctrl_lock);
tty: localise the lock The termios and other changes mean the other protections needed on the driver tty arrays should be adequate. Turn it all back on. This contains pieces folded in from the fixes made to the original patches | From: Geert Uytterhoeven <geert@linux-m68k.org> (fix m68k) | From: Paul Gortmaker <paul.gortmaker@windriver.com> (fix cris) | From: Jiri Kosina <jkosina@suze.cz> (lockdep) | From: Eric Dumazet <eric.dumazet@gmail.com> (lockdep) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 23:30:13 +08:00
/* Review - krefs on tty_link ?? */
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 (!tty->link)
return;
set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
Fix OpenSSH pty regression on close OpenSSH expects the (non-blocking) read() of pty master to return EAGAIN only if it has received all of the slave-side output after it has received SIGCHLD. This used to work on pre-3.12 kernels. This fix effectively forces non-blocking read() and poll() to block for parallel i/o to complete for all ttys. It also unwinds these changes: 1) f8747d4a466ab2cafe56112c51b3379f9fdb7a12 tty: Fix pty master read() after slave closes 2) 52bce7f8d4fc633c9a9d0646eef58ba6ae9a3b73 pty, n_tty: Simplify input processing on final close 3) 1a48632ffed61352a7810ce089dc5a8bcd505a60 pty: Fix input race when closing Inspired by analysis and patch from Marc Aurele La France <tsi@tuyoix.net> Reported-by: Volth <openssh@volth.com> Reported-by: Marc Aurele La France <tsi@tuyoix.net> BugLink: https://bugzilla.mindrot.org/show_bug.cgi?id=52 BugLink: https://bugzilla.mindrot.org/show_bug.cgi?id=2492 Signed-off-by: Brian Bloniarz <brian.bloniarz@gmail.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07 05:16:30 +08:00
wake_up_interruptible(&tty->link->read_wait);
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
wake_up_interruptible(&tty->link->write_wait);
if (tty->driver->subtype == PTY_TYPE_MASTER) {
set_bit(TTY_OTHER_CLOSED, &tty->flags);
Revert "TTY: pty, remove superfluous ptm test" This reverts commit a50f724a432997321cabb6c9e665c28e34850f78. Sasha reported that this causes problems, so revert it. Cc: Alan Cox <alan@linux.intel.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-25 05:56:36 +08:00
#ifdef CONFIG_UNIX98_PTYS
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
if (tty->driver == ptm_driver) {
tty: cleanup checkpatch warning in pty.c spaces are used for indent in 3 places of tty/pty.c, we change it to tab. Signed-off-by: Cong Ding <dinggnu@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-12 12:01:22 +08:00
mutex_lock(&devpts_mutex);
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
if (tty->link->driver_data)
devpts_pty_kill(tty->link->driver_data);
tty: cleanup checkpatch warning in pty.c spaces are used for indent in 3 places of tty/pty.c, we change it to tab. Signed-off-by: Cong Ding <dinggnu@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-12 12:01:22 +08:00
mutex_unlock(&devpts_mutex);
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
}
Revert "TTY: pty, remove superfluous ptm test" This reverts commit a50f724a432997321cabb6c9e665c28e34850f78. Sasha reported that this causes problems, so revert it. Cc: Alan Cox <alan@linux.intel.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-25 05:56:36 +08:00
#endif
tty: avoid recursive BTM in pty_close When the console has been redirected, a hangup of the tty will cause tty_release to be called under the big tty_mutex, which leads to a deadlock because hangup is also called under the BTM. This moves the BTM deeper into the tty_hangup function so we can close the redirected tty without holding the BTM. In case of pty, we now need to drop the BTM before calling tty_vhangup. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Tony Luck <tony.luck@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: John Kacur <jkacur@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-18 20:58:07 +08:00
tty_vhangup(tty->link);
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 unthrottle routine is called by the line discipline to signal
* that it can receive more characters. For PTY's, the TTY_THROTTLED
* flag is always set, to force the line discipline to always call the
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
* unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
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
* characters in the queue. This is necessary since each time this
* happens, we need to wake up any sleeping processes that could be
* (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
* for the pty buffer to be drained.
*/
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
static void pty_unthrottle(struct tty_struct *tty)
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
{
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
tty_wakeup(tty->link);
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
set_bit(TTY_THROTTLED, &tty->flags);
}
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
/**
* pty_write - write to a pty
* @tty: the tty we write from
* @buf: kernel buffer of data
* @count: bytes to write
pty: Narrow the race on ldisc locking The pty code has always been buggy on its ldisc handling. The recent changes made the window for the race much bigger. Pending fixing it properly which is not at all trivial, at least make the race small again so we don't disrupt other dev work. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 00:01:13 +08:00
*
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
* Our "hardware" write method. Data is coming from the ldisc which
* may be in a non sleeping state. We simply throw this at the other
* end of the link as if we were an IRQ handler receiving stuff for
* the other side of the pty/tty pair.
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
*/
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
pty: don't limit the writes to 'pty_space()' inside 'pty_write()' The whole write-room thing is something that is up to the _caller_ to worry about, not the pty layer itself. The total buffer space will still be limited by the buffering routines themselves, so there is no advantage or need in having pty_write() artificially limit the size somehow. And what happened was that the caller (the n_tty line discipline, in this case) may have verified that there is room for 2 bytes to be written (for NL -> CRNL expansion), and it used to then do those writes as two single-byte writes. And if the first byte written (CR) then caused a new tty buffer to be allocated, pty_space() may have returned zero when trying to write the second byte (LF), and then incorrectly failed the write - leading to a lost newline character. This should finally fix http://bugzilla.kernel.org/show_bug.cgi?id=14015 Reported-by: Mikael Pettersson <mikpe@it.uu.se> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-06 04:27:10 +08:00
static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
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
{
struct tty_struct *to = tty->link;
tty: Fix data race in tty_insert_flip_string_fixed_flag Unlike normal serials, in pty layer, there is no guarantee that multiple threads don't insert input characters at the same time. If it is happened, tty_insert_flip_string_fixed_flag can be executed concurrently. This can lead slab out-of-bounds write in tty_insert_flip_string_fixed_flag. Call sequences are as follows. CPU0 CPU1 n_tty_ioctl_helper n_tty_ioctl_helper __start_tty tty_send_xchar tty_wakeup pty_write n_hdlc_tty_wakeup tty_insert_flip_string n_hdlc_send_frames tty_insert_flip_string_fixed_flag pty_write tty_insert_flip_string tty_insert_flip_string_fixed_flag To fix the race, acquire port->lock in pty_write() before it inserts input characters to tty buffer. It prevents multiple threads from inserting input characters concurrently. The crash log is as follows: BUG: KASAN: slab-out-of-bounds in tty_insert_flip_string_fixed_flag+0xb5/ 0x130 drivers/tty/tty_buffer.c:316 at addr ffff880114fcc121 Write of size 1792 by task syz-executor0/30017 CPU: 1 PID: 30017 Comm: syz-executor0 Not tainted 4.8.0 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 0000000000000000 ffff88011638f888 ffffffff81694cc3 ffff88007d802140 ffff880114fcb300 ffff880114fcc300 ffff880114fcb300 ffff88011638f8b0 ffffffff8130075c ffff88011638f940 ffff88007d802140 ffff880194fcc121 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0xb3/0x110 lib/dump_stack.c:51 kasan_object_err+0x1c/0x70 mm/kasan/report.c:156 print_address_description mm/kasan/report.c:194 [inline] kasan_report_error+0x1f7/0x4e0 mm/kasan/report.c:283 kasan_report+0x36/0x40 mm/kasan/report.c:303 check_memory_region_inline mm/kasan/kasan.c:292 [inline] check_memory_region+0x13e/0x1a0 mm/kasan/kasan.c:299 memcpy+0x37/0x50 mm/kasan/kasan.c:335 tty_insert_flip_string_fixed_flag+0xb5/0x130 drivers/tty/tty_buffer.c:316 tty_insert_flip_string include/linux/tty_flip.h:35 [inline] pty_write+0x7f/0xc0 drivers/tty/pty.c:115 n_hdlc_send_frames+0x1d4/0x3b0 drivers/tty/n_hdlc.c:419 n_hdlc_tty_wakeup+0x73/0xa0 drivers/tty/n_hdlc.c:496 tty_wakeup+0x92/0xb0 drivers/tty/tty_io.c:601 __start_tty.part.26+0x66/0x70 drivers/tty/tty_io.c:1018 __start_tty+0x34/0x40 drivers/tty/tty_io.c:1013 n_tty_ioctl_helper+0x146/0x1e0 drivers/tty/tty_ioctl.c:1138 n_hdlc_tty_ioctl+0xb3/0x2b0 drivers/tty/n_hdlc.c:794 tty_ioctl+0xa85/0x16d0 drivers/tty/tty_io.c:2992 vfs_ioctl fs/ioctl.c:43 [inline] do_vfs_ioctl+0x13e/0xba0 fs/ioctl.c:679 SYSC_ioctl fs/ioctl.c:694 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 entry_SYSCALL_64_fastpath+0x1f/0xbd Signed-off-by: DaeRyong Jeong <threeearcat@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-30 23:27:04 +08:00
unsigned long flags;
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
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
if (tty->stopped)
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;
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
if (c > 0) {
tty: Fix data race in tty_insert_flip_string_fixed_flag Unlike normal serials, in pty layer, there is no guarantee that multiple threads don't insert input characters at the same time. If it is happened, tty_insert_flip_string_fixed_flag can be executed concurrently. This can lead slab out-of-bounds write in tty_insert_flip_string_fixed_flag. Call sequences are as follows. CPU0 CPU1 n_tty_ioctl_helper n_tty_ioctl_helper __start_tty tty_send_xchar tty_wakeup pty_write n_hdlc_tty_wakeup tty_insert_flip_string n_hdlc_send_frames tty_insert_flip_string_fixed_flag pty_write tty_insert_flip_string tty_insert_flip_string_fixed_flag To fix the race, acquire port->lock in pty_write() before it inserts input characters to tty buffer. It prevents multiple threads from inserting input characters concurrently. The crash log is as follows: BUG: KASAN: slab-out-of-bounds in tty_insert_flip_string_fixed_flag+0xb5/ 0x130 drivers/tty/tty_buffer.c:316 at addr ffff880114fcc121 Write of size 1792 by task syz-executor0/30017 CPU: 1 PID: 30017 Comm: syz-executor0 Not tainted 4.8.0 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 0000000000000000 ffff88011638f888 ffffffff81694cc3 ffff88007d802140 ffff880114fcb300 ffff880114fcc300 ffff880114fcb300 ffff88011638f8b0 ffffffff8130075c ffff88011638f940 ffff88007d802140 ffff880194fcc121 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0xb3/0x110 lib/dump_stack.c:51 kasan_object_err+0x1c/0x70 mm/kasan/report.c:156 print_address_description mm/kasan/report.c:194 [inline] kasan_report_error+0x1f7/0x4e0 mm/kasan/report.c:283 kasan_report+0x36/0x40 mm/kasan/report.c:303 check_memory_region_inline mm/kasan/kasan.c:292 [inline] check_memory_region+0x13e/0x1a0 mm/kasan/kasan.c:299 memcpy+0x37/0x50 mm/kasan/kasan.c:335 tty_insert_flip_string_fixed_flag+0xb5/0x130 drivers/tty/tty_buffer.c:316 tty_insert_flip_string include/linux/tty_flip.h:35 [inline] pty_write+0x7f/0xc0 drivers/tty/pty.c:115 n_hdlc_send_frames+0x1d4/0x3b0 drivers/tty/n_hdlc.c:419 n_hdlc_tty_wakeup+0x73/0xa0 drivers/tty/n_hdlc.c:496 tty_wakeup+0x92/0xb0 drivers/tty/tty_io.c:601 __start_tty.part.26+0x66/0x70 drivers/tty/tty_io.c:1018 __start_tty+0x34/0x40 drivers/tty/tty_io.c:1013 n_tty_ioctl_helper+0x146/0x1e0 drivers/tty/tty_ioctl.c:1138 n_hdlc_tty_ioctl+0xb3/0x2b0 drivers/tty/n_hdlc.c:794 tty_ioctl+0xa85/0x16d0 drivers/tty/tty_io.c:2992 vfs_ioctl fs/ioctl.c:43 [inline] do_vfs_ioctl+0x13e/0xba0 fs/ioctl.c:679 SYSC_ioctl fs/ioctl.c:694 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 entry_SYSCALL_64_fastpath+0x1f/0xbd Signed-off-by: DaeRyong Jeong <threeearcat@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-30 23:27:04 +08:00
spin_lock_irqsave(&to->port->lock, flags);
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
/* Stuff the data into the input queue of the other end */
TTY: switch tty_insert_flip_string Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. tty_insert_flip_string this time. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 22:53:04 +08:00
c = tty_insert_flip_string(to->port, buf, c);
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
/* And shovel */
tty: Remove extra wakeup from pty write() path Acquiring the write_wait queue spin lock now accounts for the largest slice of cpu time on the tty write path. Two factors contribute to this situation; a overly-pessimistic line discipline write loop which _always_ sets up a wait loop even if i/o will immediately succeed, and on ptys, a wakeup storm from reads and writes. Writer wakeup does not need to be performed by the pty driver. Firstly, since the actual i/o is performed within the write, the line discipline write loop will continue while space remains in the flip buffers. Secondly, when space becomes avail in the line discipline receive buffer (and thus also in the flip buffers), the pty unthrottle re-wakes the writer (non-flow-controlled line disciplines unconditionally unthrottle the driver when data is received). Thus, existing in-kernel i/o is guaranteed to advance. Finally, writer wakeup occurs at the conclusion of the line discipline write (in tty_write_unlock()). This guarantees that any user-space write waiters are woken to continue additional i/o. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-24 20:29:57 +08:00
if (c)
TTY: switch tty_flip_buffer_push Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 22:53:06 +08:00
tty_flip_buffer_push(to->port);
tty: Fix data race in tty_insert_flip_string_fixed_flag Unlike normal serials, in pty layer, there is no guarantee that multiple threads don't insert input characters at the same time. If it is happened, tty_insert_flip_string_fixed_flag can be executed concurrently. This can lead slab out-of-bounds write in tty_insert_flip_string_fixed_flag. Call sequences are as follows. CPU0 CPU1 n_tty_ioctl_helper n_tty_ioctl_helper __start_tty tty_send_xchar tty_wakeup pty_write n_hdlc_tty_wakeup tty_insert_flip_string n_hdlc_send_frames tty_insert_flip_string_fixed_flag pty_write tty_insert_flip_string tty_insert_flip_string_fixed_flag To fix the race, acquire port->lock in pty_write() before it inserts input characters to tty buffer. It prevents multiple threads from inserting input characters concurrently. The crash log is as follows: BUG: KASAN: slab-out-of-bounds in tty_insert_flip_string_fixed_flag+0xb5/ 0x130 drivers/tty/tty_buffer.c:316 at addr ffff880114fcc121 Write of size 1792 by task syz-executor0/30017 CPU: 1 PID: 30017 Comm: syz-executor0 Not tainted 4.8.0 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 0000000000000000 ffff88011638f888 ffffffff81694cc3 ffff88007d802140 ffff880114fcb300 ffff880114fcc300 ffff880114fcb300 ffff88011638f8b0 ffffffff8130075c ffff88011638f940 ffff88007d802140 ffff880194fcc121 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0xb3/0x110 lib/dump_stack.c:51 kasan_object_err+0x1c/0x70 mm/kasan/report.c:156 print_address_description mm/kasan/report.c:194 [inline] kasan_report_error+0x1f7/0x4e0 mm/kasan/report.c:283 kasan_report+0x36/0x40 mm/kasan/report.c:303 check_memory_region_inline mm/kasan/kasan.c:292 [inline] check_memory_region+0x13e/0x1a0 mm/kasan/kasan.c:299 memcpy+0x37/0x50 mm/kasan/kasan.c:335 tty_insert_flip_string_fixed_flag+0xb5/0x130 drivers/tty/tty_buffer.c:316 tty_insert_flip_string include/linux/tty_flip.h:35 [inline] pty_write+0x7f/0xc0 drivers/tty/pty.c:115 n_hdlc_send_frames+0x1d4/0x3b0 drivers/tty/n_hdlc.c:419 n_hdlc_tty_wakeup+0x73/0xa0 drivers/tty/n_hdlc.c:496 tty_wakeup+0x92/0xb0 drivers/tty/tty_io.c:601 __start_tty.part.26+0x66/0x70 drivers/tty/tty_io.c:1018 __start_tty+0x34/0x40 drivers/tty/tty_io.c:1013 n_tty_ioctl_helper+0x146/0x1e0 drivers/tty/tty_ioctl.c:1138 n_hdlc_tty_ioctl+0xb3/0x2b0 drivers/tty/n_hdlc.c:794 tty_ioctl+0xa85/0x16d0 drivers/tty/tty_io.c:2992 vfs_ioctl fs/ioctl.c:43 [inline] do_vfs_ioctl+0x13e/0xba0 fs/ioctl.c:679 SYSC_ioctl fs/ioctl.c:694 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 entry_SYSCALL_64_fastpath+0x1f/0xbd Signed-off-by: DaeRyong Jeong <threeearcat@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-30 23:27:04 +08:00
spin_unlock_irqrestore(&to->port->lock, flags);
pty: Narrow the race on ldisc locking The pty code has always been buggy on its ldisc handling. The recent changes made the window for the race much bigger. Pending fixing it properly which is not at all trivial, at least make the race small again so we don't disrupt other dev work. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-17 00:01:13 +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 c;
}
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
/**
* pty_write_room - write space
* @tty: tty we are writing from
*
* Report how many bytes the ldisc can send into the queue for
* the other device.
*/
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
static int pty_write_room(struct tty_struct *tty)
{
pty: fix data loss when stopped (^S/^Q) Commit d945cb9cc ("pty: Rework the pty layer to use the normal buffering logic") dropped the test for 'tty->stopped' in pty_write_room(), which then causes the n_tty line discipline thing to not throttle the data properly when the tty is stopped. So instead of pausing the write due to the tty being stopped, the ldisc layer would go ahead and push it down to the pty. The pty write() routine would then refuse to take the data (because it _did_ check 'stopped'), and the data wouldn't actually be written. This whole stopped test should eventually be moved into the tty ldisc layer rather than have low-level tty drivers care about these things, but right now the fix is to just re-instate the missing pty 'stopped' handling. Reported-and-tested-by: Artur Skawina <art.08.09@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-11 04:21:19 +08:00
if (tty->stopped)
return 0;
pty: Fix overlimit memory use The pty_space() computation is broken; the space already consumed in the tty buffer is not accounted for. Use tty_buffer_set_limit(), which enforces the limit automatically. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-17 04:22:14 +08:00
return tty_buffer_space_avail(tty->link->port);
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
}
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
/**
* pty_chars_in_buffer - characters currently in our tx queue
* @tty: our tty
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
*
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
* Report how much we have in the transmit queue. As everything is
* instantly at the other end this is easy to implement.
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
*/
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +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
static int pty_chars_in_buffer(struct tty_struct *tty)
{
pty: Rework the pty layer to use the normal buffering logic This fixes the ppp problems and various other issues with call locking caused by one side of a pty called in one locking context trying to match another with differing rules on the other side. We also get a big slack space to work with that means we can bury the flow control deadlock case for any conceivable real world situation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-07 23:39:41 +08:00
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
}
/* Set the lock flag on a pty */
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
static int pty_set_lock(struct tty_struct *tty, int __user *arg)
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 val;
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
if (get_user(val, arg))
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 -EFAULT;
if (val)
set_bit(TTY_PTY_LOCK, &tty->flags);
else
clear_bit(TTY_PTY_LOCK, &tty->flags);
return 0;
}
tty: Add get- ioctls to fetch tty status v3 For checkpoint/restore we need to know if tty has exclusive or packet mode set, as well as if pty is currently locked. Just to be able to restore this characteristics. For this sake the following ioctl codes are introduced - TIOCGPKT to get packet mode state - TIOCGPTLCK to get Pty locked state - TIOCGEXCL to get Exclusive mode state Note this ioctls are a bit unsafe in terms of data obtained consistency. The tty characteristics might be changed right after ioctl complete. Keep it in mind and use this ioctl carefully. v2: - Use TIOC prefix for ioctl codes (by jslaby@) Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Alan Cox <alan@lxorguk.ukuu.org.uk> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:22 +08:00
static int pty_get_lock(struct tty_struct *tty, int __user *arg)
{
int locked = test_bit(TTY_PTY_LOCK, &tty->flags);
return put_user(locked, arg);
}
tty: pty - Move TIOCPKT handling into pty.c Since this ioctl is for pty devices only move it to pty.c. v2: - drop PTY_TYPE_MASTER test since it's master peer ioctl anyway (by jslaby@) Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:20 +08:00
/* Set the packet mode on a pty */
static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
{
int pktmode;
if (get_user(pktmode, arg))
return -EFAULT;
tty: Use spin_lock_irq() for ctrl_lock when interrupts enabled Interrupts are enabled in the n_tty_read() loop, ioctl(TIOCPKT) and pty driver flush_buffer() routine; no need to save and restore local interrupt state. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:25 +08:00
spin_lock_irq(&tty->ctrl_lock);
tty: pty - Move TIOCPKT handling into pty.c Since this ioctl is for pty devices only move it to pty.c. v2: - drop PTY_TYPE_MASTER test since it's master peer ioctl anyway (by jslaby@) Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:20 +08:00
if (pktmode) {
if (!tty->packet) {
tty->link->ctrl_status = 0;
pty: Fix packet mode setting race Because pty_set_pktmode() does not claim the slave's ctrl_lock to clear ->ctrl_status (to avoid unnecessary lock nesting), pty_set_pktmode() may accidentally erase new ->ctrl_status updates. For example, CPU 0 | CPU 1 pty_set_pktmode() | pty_start() spin_lock(master's ctrl_lock) | tty->packet = 1 | | if (tty->link->packet) | spin_lock(slave's ctrl_lock) | tty->ctrl_status = TIOCPKT_START tty->link->ctrl_status = 0 | Ensure the clear of ->ctrl_status occurs before packet mode is set (and observable on another cpu). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:27 +08:00
smp_mb();
tty->packet = 1;
tty: pty - Move TIOCPKT handling into pty.c Since this ioctl is for pty devices only move it to pty.c. v2: - drop PTY_TYPE_MASTER test since it's master peer ioctl anyway (by jslaby@) Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:20 +08:00
}
} else
tty->packet = 0;
tty: Use spin_lock_irq() for ctrl_lock when interrupts enabled Interrupts are enabled in the n_tty_read() loop, ioctl(TIOCPKT) and pty driver flush_buffer() routine; no need to save and restore local interrupt state. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:25 +08:00
spin_unlock_irq(&tty->ctrl_lock);
tty: pty - Move TIOCPKT handling into pty.c Since this ioctl is for pty devices only move it to pty.c. v2: - drop PTY_TYPE_MASTER test since it's master peer ioctl anyway (by jslaby@) Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:20 +08:00
return 0;
}
tty: Add get- ioctls to fetch tty status v3 For checkpoint/restore we need to know if tty has exclusive or packet mode set, as well as if pty is currently locked. Just to be able to restore this characteristics. For this sake the following ioctl codes are introduced - TIOCGPKT to get packet mode state - TIOCGPTLCK to get Pty locked state - TIOCGEXCL to get Exclusive mode state Note this ioctls are a bit unsafe in terms of data obtained consistency. The tty characteristics might be changed right after ioctl complete. Keep it in mind and use this ioctl carefully. v2: - Use TIOC prefix for ioctl codes (by jslaby@) Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Alan Cox <alan@lxorguk.ukuu.org.uk> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:22 +08:00
/* Get the packet mode of a pty */
static int pty_get_pktmode(struct tty_struct *tty, int __user *arg)
{
int pktmode = tty->packet;
return put_user(pktmode, arg);
}
tty: Add EXTPROC support for LINEMODE This patch is against the 2.6.34 source. Paraphrased from the 1989 BSD patch by David Borman @ cray.com: These are the changes needed for the kernel to support LINEMODE in the server. There is a new bit in the termios local flag word, EXTPROC. When this bit is set, several aspects of the terminal driver are disabled. Input line editing, character echo, and mapping of signals are all disabled. This allows the telnetd to turn off these functions when in linemode, but still keep track of what state the user wants the terminal to be in. New ioctl: TIOCSIG Generate a signal to processes in the current process group of the pty. There is a new mode for packet driver, the TIOCPKT_IOCTL bit. When packet mode is turned on in the pty, and the EXTPROC bit is set, then whenever the state of the pty is changed, the next read on the master side of the pty will have the TIOCPKT_IOCTL bit set. This allows the process on the server side of the pty to know when the state of the terminal has changed; it can then issue the appropriate ioctl to retrieve the new state. Since the original BSD patches accompanied the source code for telnet I've left that reference here, but obviously the feature is useful for any remote terminal protocol, including ssh. The corresponding feature has existed in the BSD tty driver since 1989. For historical reference, a good copy of the relevant files can be found here: http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741 Signed-off-by: Howard Chu <hyc@symas.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-23 01:14:49 +08:00
/* Send a signal to the slave */
static int pty_signal(struct tty_struct *tty, int sig)
{
struct pid *pgrp;
tty: Prevent untrappable signals from malicious program Commit 26df6d13406d1a5 ("tty: Add EXTPROC support for LINEMODE") allows a process which has opened a pty master to send _any_ signal to the process group of the pty slave. Although potentially exploitable by a malicious program running a setuid program on a pty slave, it's unknown if this exploit currently exists. Limit to signals actually used. Cc: Theodore Ts'o <tytso@mit.edu> Cc: Howard Chu <hyc@symas.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Cc: <stable@vger.kernel.org> # 2.6.36+ Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-20 02:05:03 +08:00
if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP)
return -EINVAL;
tty: Add EXTPROC support for LINEMODE This patch is against the 2.6.34 source. Paraphrased from the 1989 BSD patch by David Borman @ cray.com: These are the changes needed for the kernel to support LINEMODE in the server. There is a new bit in the termios local flag word, EXTPROC. When this bit is set, several aspects of the terminal driver are disabled. Input line editing, character echo, and mapping of signals are all disabled. This allows the telnetd to turn off these functions when in linemode, but still keep track of what state the user wants the terminal to be in. New ioctl: TIOCSIG Generate a signal to processes in the current process group of the pty. There is a new mode for packet driver, the TIOCPKT_IOCTL bit. When packet mode is turned on in the pty, and the EXTPROC bit is set, then whenever the state of the pty is changed, the next read on the master side of the pty will have the TIOCPKT_IOCTL bit set. This allows the process on the server side of the pty to know when the state of the terminal has changed; it can then issue the appropriate ioctl to retrieve the new state. Since the original BSD patches accompanied the source code for telnet I've left that reference here, but obviously the feature is useful for any remote terminal protocol, including ssh. The corresponding feature has existed in the BSD tty driver since 1989. For historical reference, a good copy of the relevant files can be found here: http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741 Signed-off-by: Howard Chu <hyc@symas.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-23 01:14:49 +08:00
if (tty->link) {
tty: Replace open-coded tty_get_pgrp() Replace open-coded instances of tty_get_pgrp(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 02:59:45 +08:00
pgrp = tty_get_pgrp(tty->link);
if (pgrp)
kill_pgrp(pgrp, sig, 1);
tty: Add EXTPROC support for LINEMODE This patch is against the 2.6.34 source. Paraphrased from the 1989 BSD patch by David Borman @ cray.com: These are the changes needed for the kernel to support LINEMODE in the server. There is a new bit in the termios local flag word, EXTPROC. When this bit is set, several aspects of the terminal driver are disabled. Input line editing, character echo, and mapping of signals are all disabled. This allows the telnetd to turn off these functions when in linemode, but still keep track of what state the user wants the terminal to be in. New ioctl: TIOCSIG Generate a signal to processes in the current process group of the pty. There is a new mode for packet driver, the TIOCPKT_IOCTL bit. When packet mode is turned on in the pty, and the EXTPROC bit is set, then whenever the state of the pty is changed, the next read on the master side of the pty will have the TIOCPKT_IOCTL bit set. This allows the process on the server side of the pty to know when the state of the terminal has changed; it can then issue the appropriate ioctl to retrieve the new state. Since the original BSD patches accompanied the source code for telnet I've left that reference here, but obviously the feature is useful for any remote terminal protocol, including ssh. The corresponding feature has existed in the BSD tty driver since 1989. For historical reference, a good copy of the relevant files can be found here: http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741 Signed-off-by: Howard Chu <hyc@symas.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-23 01:14:49 +08:00
put_pid(pgrp);
}
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
static void pty_flush_buffer(struct tty_struct *tty)
{
struct tty_struct *to = tty->link;
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +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 (!to)
return;
pty: Fix buffer flush deadlock The pty driver does not clear its write buffer when commanded. This is to avoid an apparent deadlock between parallel flushes from both pty ends; specifically when handling either BRK or INTR input. However, parallel flushes from this source is not possible since the pty master can never be set to BRKINT or ISIG. Parallel flushes from other sources are possible but these do not threaten deadlocks. Annotate the tty buffer mutex for lockdep to represent the nested tty_buffer locking which occurs when the pty slave is processing input (its buffer mutex held) and receives INTR or BRK and acquires the linked tty buffer mutex via tty_buffer_flush(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-18 04:42:05 +08:00
tty: pty: Fix ldisc flush after userspace become aware of the data already While using emacs, cat or others' commands in konsole with recent kernels, I have met many times that CTRL-C freeze konsole. After konsole freeze I can't type anything, then I have to open a new one, it is very annoying. See bug report: https://bugs.kde.org/show_bug.cgi?id=175283 The platform in that bug report is Solaris, but now the pty in linux has the same problem or the same behavior as Solaris :) It has high possibility to trigger the problem follow steps below: Note: In my test, BigFile is a text file whose size is bigger than 1G 1:open konsole 1:cat BigFile 2:CTRL-C After some digging, I find out the reason is that commit 1d1d14da12e7 ("pty: Fix buffer flush deadlock") changes the behavior of pty_flush_buffer. Thread A Thread B -------- -------- 1:n_tty_poll return POLLIN 2:CTRL-C trigger pty_flush_buffer tty_buffer_flush n_tty_flush_buffer 3:attempt to check count of chars: ioctl(fd, TIOCINQ, &available) available is equal to 0 4:read(fd, buffer, avaiable) return 0 5:konsole close fd Yes, I know we could use the same patch included in the BUG report as a workaround for linux platform too. But I think the data in ldisc is belong to application of another side, we shouldn't clear it when we want to flush write buffer of this side in pty_flush_buffer. So I think it is better to disable ldisc flush in pty_flush_buffer, because its new hehavior bring no benefit except that it mess up the behavior between POLLIN, and TIOCINQ or FIONREAD. Also I find no flush_buffer function in others' tty driver has the same behavior as current pty_flush_buffer. Fixes: 1d1d14da12e7 ("pty: Fix buffer flush deadlock") CC: stable@vger.kernel.org # v4.0+ Signed-off-by: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-22 19:37:08 +08:00
tty_buffer_flush(to, NULL);
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 (to->packet) {
tty: Use spin_lock_irq() for ctrl_lock when interrupts enabled Interrupts are enabled in the n_tty_read() loop, ioctl(TIOCPKT) and pty driver flush_buffer() routine; no need to save and restore local interrupt state. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:25 +08:00
spin_lock_irq(&tty->ctrl_lock);
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
tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
wake_up_interruptible(&to->read_wait);
tty: Use spin_lock_irq() for ctrl_lock when interrupts enabled Interrupts are enabled in the n_tty_read() loop, ioctl(TIOCPKT) and pty driver flush_buffer() routine; no need to save and restore local interrupt state. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:25 +08:00
spin_unlock_irq(&tty->ctrl_lock);
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
}
}
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
static int pty_open(struct tty_struct *tty, struct file *filp)
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 (!tty || !tty->link)
tty: Fix transient pty write() EIO Commit 699390354da6c258b65bf8fa79cfd5feaede50b6 ('pty: Ignore slave pty close() if never successfully opened') introduced a bug with ptys whereby a write() in parallel with an open() on an existing pty could mistakenly indicate an I/O error. Only indicate an I/O error if the condition on open() actually exists. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Cc: stable <stable@vger.kernel.org> # 3.9 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-14 03:56:37 +08:00
return -ENODEV;
pty: Ignore slave pty close() if never successfully opened If the master and slave ptys are opened in parallel, the slave open fails because the pty is still locked. This is as designed. However, pty_close() is still called for the slave pty which sets TTY_OTHER_CLOSED in the master pty. This can cause the master open to fail as well. Use a common pattern in other tty drivers by setting TTY_IO_ERROR until the open is successful and only closing the pty if not set. Note: the master pty always closes regardless of whether the open was successful, so that proper cleanup can occur. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-31 01:43:50 +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
if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
goto out;
if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
goto out;
pty: Ignore slave open count for master pty open Multiple slave pty opens may be performed in parallel with the master open. Of course, all the slave opens will fail because the master pty is still locked but during this time the slave pty count will be artificially greater than 1. This is should not cause the master pty open to fail. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-31 01:43:52 +08:00
if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
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
goto out;
pty: Ignore slave pty close() if never successfully opened If the master and slave ptys are opened in parallel, the slave open fails because the pty is still locked. This is as designed. However, pty_close() is still called for the slave pty which sets TTY_OTHER_CLOSED in the master pty. This can cause the master open to fail as well. Use a common pattern in other tty drivers by setting TTY_IO_ERROR until the open is successful and only closing the pty if not set. Note: the master pty always closes regardless of whether the open was successful, so that proper cleanup can occur. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-31 01:43:50 +08:00
clear_bit(TTY_IO_ERROR, &tty->flags);
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
clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
set_bit(TTY_THROTTLED, &tty->flags);
tty: Fix transient pty write() EIO Commit 699390354da6c258b65bf8fa79cfd5feaede50b6 ('pty: Ignore slave pty close() if never successfully opened') introduced a bug with ptys whereby a write() in parallel with an open() on an existing pty could mistakenly indicate an I/O error. Only indicate an I/O error if the condition on open() actually exists. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Cc: stable <stable@vger.kernel.org> # 3.9 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-14 03:56:37 +08:00
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
out:
tty: Fix transient pty write() EIO Commit 699390354da6c258b65bf8fa79cfd5feaede50b6 ('pty: Ignore slave pty close() if never successfully opened') introduced a bug with ptys whereby a write() in parallel with an open() on an existing pty could mistakenly indicate an I/O error. Only indicate an I/O error if the condition on open() actually exists. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Cc: stable <stable@vger.kernel.org> # 3.9 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-14 03:56:37 +08:00
set_bit(TTY_IO_ERROR, &tty->flags);
return -EIO;
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
}
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
static void pty_set_termios(struct tty_struct *tty,
struct ktermios *old_termios)
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
{
tty: Move pty-specific set_termios() handling to pty driver Packet mode is unique to the pty driver; move the packet mode state change code from the generic tty ioctl handler to the pty driver. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:23 +08:00
/* See if packet mode change of state. */
if (tty->link && tty->link->packet) {
tty: Use termios c_*flag macros Expressions of the form "tty->termios.c_*flag & FLAG" are more clearly expressed with the termios flags macros, I_FLAG(), C_FLAG(), O_FLAG(), and L_FLAG(). Convert treewide. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-11 12:36:15 +08:00
int extproc = (old_termios->c_lflag & EXTPROC) | L_EXTPROC(tty);
tty: Move pty-specific set_termios() handling to pty driver Packet mode is unique to the pty driver; move the packet mode state change code from the generic tty ioctl handler to the pty driver. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:23 +08:00
int old_flow = ((old_termios->c_iflag & IXON) &&
(old_termios->c_cc[VSTOP] == '\023') &&
(old_termios->c_cc[VSTART] == '\021'));
int new_flow = (I_IXON(tty) &&
STOP_CHAR(tty) == '\023' &&
START_CHAR(tty) == '\021');
if ((old_flow != new_flow) || extproc) {
pty: Use spin_lock_irq() for pty_set_termios() The tty driver's set_termios() method is called with interrupts enabled; there is no need to save and restore the local interrupt state. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:24 +08:00
spin_lock_irq(&tty->ctrl_lock);
tty: Move pty-specific set_termios() handling to pty driver Packet mode is unique to the pty driver; move the packet mode state change code from the generic tty ioctl handler to the pty driver. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:23 +08:00
if (old_flow != new_flow) {
tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
if (new_flow)
tty->ctrl_status |= TIOCPKT_DOSTOP;
else
tty->ctrl_status |= TIOCPKT_NOSTOP;
}
if (extproc)
tty->ctrl_status |= TIOCPKT_IOCTL;
pty: Use spin_lock_irq() for pty_set_termios() The tty driver's set_termios() method is called with interrupts enabled; there is no need to save and restore the local interrupt state. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:24 +08:00
spin_unlock_irq(&tty->ctrl_lock);
tty: Move pty-specific set_termios() handling to pty driver Packet mode is unique to the pty driver; move the packet mode state change code from the generic tty ioctl handler to the pty driver. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:23 +08:00
wake_up_interruptible(&tty->link->read_wait);
}
}
tty: move the termios object into the tty This will let us sort out a whole pile of tty related races. The alternative would be to keep points and refcount the termios objects. However 1. They are tiny anyway 2. Many devices don't use the stored copies 3. We can remove a pty special case Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-14 22:31:47 +08:00
tty->termios.c_cflag &= ~(CSIZE | PARENB);
tty->termios.c_cflag |= (CS8 | CREAD);
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
}
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
/**
* pty_do_resize - resize event
* @tty: tty being resized
pty: Fix documentation The pty changes and updates for window sizing forgot to correct the kerneldoc Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-12 03:46:49 +08:00
* @ws: window size being set.
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
*
tree-wide: Assorted spelling fixes In particular, several occurances of funny versions of 'success', 'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address', 'beginning', 'desirable', 'separate' and 'necessary' are fixed. Signed-off-by: Daniel Mack <daniel@caiaq.de> Cc: Joe Perches <joe@perches.com> Cc: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-03 08:01:28 +08:00
* Update the termios variables and send the necessary signals to
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
* peform a terminal resize correctly
*/
pty: Mark pty_resize static Nothing outside of drivers/tty/pty.c references pty_resize. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-19 13:27:40 +08:00
static int pty_resize(struct tty_struct *tty, struct winsize *ws)
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
{
struct pid *pgrp, *rpgrp;
struct tty_struct *pty = tty->link;
/* For a PTY we need to lock the tty side */
tty: Fix lock order in tty_do_resize() Commits 6a1c0680cf3ba94356ecd58833e1540c93472a57 and 9356b535fcb71db494fc434acceb79f56d15bda2, respectively 'tty: Convert termios_mutex to termios_rwsem' and 'n_tty: Access termios values safely' introduced a circular lock dependency with console_lock and termios_rwsem. The lockdep report [1] shows that n_tty_write() will attempt to claim console_lock while holding the termios_rwsem, whereas tty_do_resize() may already hold the console_lock while claiming the termios_rwsem. Since n_tty_write() and tty_do_resize() do not contend over the same data -- the tty->winsize structure -- correct the lock dependency by introducing a new lock which specifically serializes access to tty->winsize only. [1] Lockdep report ====================================================== [ INFO: possible circular locking dependency detected ] 3.10.0-0+tip-xeon+lockdep #0+tip Not tainted ------------------------------------------------------- modprobe/277 is trying to acquire lock: (&tty->termios_rwsem){++++..}, at: [<ffffffff81452656>] tty_do_resize+0x36/0xe0 but task is already holding lock: ((fb_notifier_list).rwsem){.+.+.+}, at: [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 ((fb_notifier_list).rwsem){.+.+.+}: [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff8175b797>] down_read+0x47/0x5c [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper] [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau] [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau] [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm] [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau] [<ffffffff813b13db>] local_pci_probe+0x4b/0x80 [<ffffffff813b1701>] pci_device_probe+0x111/0x120 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0 [<ffffffff81497bab>] __driver_attach+0xab/0xb0 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0 [<ffffffff814971fe>] driver_attach+0x1e/0x20 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290 [<ffffffff814982b7>] driver_register+0x77/0x170 [<ffffffff813b0454>] __pci_register_driver+0x64/0x70 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm] [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0 [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b -> #1 (console_lock){+.+.+.}: [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff810430a7>] console_lock+0x77/0x80 [<ffffffff8146b2a1>] con_flush_chars+0x31/0x50 [<ffffffff8145780c>] n_tty_write+0x1ec/0x4d0 [<ffffffff814541b9>] tty_write+0x159/0x2e0 [<ffffffff814543f5>] redirected_tty_write+0xb5/0xc0 [<ffffffff811ab9d5>] vfs_write+0xc5/0x1f0 [<ffffffff811abec5>] SyS_write+0x55/0xa0 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b -> #0 (&tty->termios_rwsem){++++..}: [<ffffffff810b65c3>] __lock_acquire+0x1c43/0x1d30 [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff8175b724>] down_write+0x44/0x70 [<ffffffff81452656>] tty_do_resize+0x36/0xe0 [<ffffffff8146c841>] vc_do_resize+0x3e1/0x4c0 [<ffffffff8146c99f>] vc_resize+0x1f/0x30 [<ffffffff813e4535>] fbcon_init+0x385/0x5a0 [<ffffffff8146a4bc>] visual_init+0xbc/0x120 [<ffffffff8146cd13>] do_bind_con_driver+0x163/0x320 [<ffffffff8146cfa1>] do_take_over_console+0x61/0x70 [<ffffffff813e2b93>] do_fbcon_takeover+0x63/0xc0 [<ffffffff813e67a5>] fbcon_event_notify+0x715/0x820 [<ffffffff81762f9d>] notifier_call_chain+0x5d/0x110 [<ffffffff8107aadc>] __blocking_notifier_call_chain+0x6c/0xc0 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper] [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau] [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau] [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm] [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau] [<ffffffff813b13db>] local_pci_probe+0x4b/0x80 [<ffffffff813b1701>] pci_device_probe+0x111/0x120 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0 [<ffffffff81497bab>] __driver_attach+0xab/0xb0 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0 [<ffffffff814971fe>] driver_attach+0x1e/0x20 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290 [<ffffffff814982b7>] driver_register+0x77/0x170 [<ffffffff813b0454>] __pci_register_driver+0x64/0x70 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm] [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0 [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b other info that might help us debug this: Chain exists of: &tty->termios_rwsem --> console_lock --> (fb_notifier_list).rwsem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((fb_notifier_list).rwsem); lock(console_lock); lock((fb_notifier_list).rwsem); lock(&tty->termios_rwsem); *** DEADLOCK *** 7 locks held by modprobe/277: #0: (&__lockdep_no_validate__){......}, at: [<ffffffff81497b5b>] __driver_attach+0x5b/0xb0 #1: (&__lockdep_no_validate__){......}, at: [<ffffffff81497b69>] __driver_attach+0x69/0xb0 #2: (drm_global_mutex){+.+.+.}, at: [<ffffffffa008a6dd>] drm_get_pci_dev+0xbd/0x2a0 [drm] #3: (registration_lock){+.+.+.}, at: [<ffffffff813d93f5>] register_framebuffer+0x25/0x320 #4: (&fb_info->lock){+.+.+.}, at: [<ffffffff813d8116>] lock_fb_info+0x26/0x60 #5: (console_lock){+.+.+.}, at: [<ffffffff813d95a4>] register_framebuffer+0x1d4/0x320 #6: ((fb_notifier_list).rwsem){.+.+.+}, at: [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0 stack backtrace: CPU: 0 PID: 277 Comm: modprobe Not tainted 3.10.0-0+tip-xeon+lockdep #0+tip Hardware name: Dell Inc. Precision WorkStation T5400 /0RW203, BIOS A11 04/30/2012 ffffffff8213e5e0 ffff8802aa2fb298 ffffffff81755f19 ffff8802aa2fb2e8 ffffffff8174f506 ffff8802aa2fa000 ffff8802aa2fb378 ffff8802aa2ea8e8 ffff8802aa2ea910 ffff8802aa2ea8e8 0000000000000006 0000000000000007 Call Trace: [<ffffffff81755f19>] dump_stack+0x19/0x1b [<ffffffff8174f506>] print_circular_bug+0x1fb/0x20c [<ffffffff810b65c3>] __lock_acquire+0x1c43/0x1d30 [<ffffffff810b775e>] ? mark_held_locks+0xae/0x120 [<ffffffff810b78d5>] ? trace_hardirqs_on_caller+0x105/0x1d0 [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff81452656>] ? tty_do_resize+0x36/0xe0 [<ffffffff8175b724>] down_write+0x44/0x70 [<ffffffff81452656>] ? tty_do_resize+0x36/0xe0 [<ffffffff81452656>] tty_do_resize+0x36/0xe0 [<ffffffff8146c841>] vc_do_resize+0x3e1/0x4c0 [<ffffffff8146c99f>] vc_resize+0x1f/0x30 [<ffffffff813e4535>] fbcon_init+0x385/0x5a0 [<ffffffff8146a4bc>] visual_init+0xbc/0x120 [<ffffffff8146cd13>] do_bind_con_driver+0x163/0x320 [<ffffffff8146cfa1>] do_take_over_console+0x61/0x70 [<ffffffff813e2b93>] do_fbcon_takeover+0x63/0xc0 [<ffffffff813e67a5>] fbcon_event_notify+0x715/0x820 [<ffffffff81762f9d>] notifier_call_chain+0x5d/0x110 [<ffffffff8107aadc>] __blocking_notifier_call_chain+0x6c/0xc0 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper] [<ffffffff8173cbcb>] ? kmemleak_alloc+0x5b/0xc0 [<ffffffff81198874>] ? kmem_cache_alloc_trace+0x104/0x290 [<ffffffffa01035e1>] ? drm_fb_helper_single_add_all_connectors+0x81/0xf0 [drm_kms_helper] [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau] [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau] [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm] [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau] [<ffffffff8175f162>] ? _raw_spin_unlock_irqrestore+0x42/0x80 [<ffffffff813b13db>] local_pci_probe+0x4b/0x80 [<ffffffff813b1701>] pci_device_probe+0x111/0x120 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0 [<ffffffff81497bab>] __driver_attach+0xab/0xb0 [<ffffffff81497b00>] ? driver_probe_device+0x3a0/0x3a0 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0 [<ffffffff814971fe>] driver_attach+0x1e/0x20 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290 [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffff814982b7>] driver_register+0x77/0x170 [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffff813b0454>] __pci_register_driver+0x64/0x70 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm] [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0 [<ffffffff81399a50>] ? ddebug_proc_open+0xb0/0xb0 [<ffffffff813855ae>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 04:43:51 +08:00
mutex_lock(&tty->winsize_mutex);
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
goto done;
tty: Replace open-coded tty_get_pgrp() Replace open-coded instances of tty_get_pgrp(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 02:59:45 +08:00
/* Signal the foreground process group of both ptys */
pgrp = tty_get_pgrp(tty);
rpgrp = tty_get_pgrp(pty);
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
if (pgrp)
kill_pgrp(pgrp, SIGWINCH, 1);
if (rpgrp != pgrp && rpgrp)
kill_pgrp(rpgrp, SIGWINCH, 1);
put_pid(pgrp);
put_pid(rpgrp);
tty->winsize = *ws;
pty->winsize = *ws; /* Never used so will go away soon */
done:
tty: Fix lock order in tty_do_resize() Commits 6a1c0680cf3ba94356ecd58833e1540c93472a57 and 9356b535fcb71db494fc434acceb79f56d15bda2, respectively 'tty: Convert termios_mutex to termios_rwsem' and 'n_tty: Access termios values safely' introduced a circular lock dependency with console_lock and termios_rwsem. The lockdep report [1] shows that n_tty_write() will attempt to claim console_lock while holding the termios_rwsem, whereas tty_do_resize() may already hold the console_lock while claiming the termios_rwsem. Since n_tty_write() and tty_do_resize() do not contend over the same data -- the tty->winsize structure -- correct the lock dependency by introducing a new lock which specifically serializes access to tty->winsize only. [1] Lockdep report ====================================================== [ INFO: possible circular locking dependency detected ] 3.10.0-0+tip-xeon+lockdep #0+tip Not tainted ------------------------------------------------------- modprobe/277 is trying to acquire lock: (&tty->termios_rwsem){++++..}, at: [<ffffffff81452656>] tty_do_resize+0x36/0xe0 but task is already holding lock: ((fb_notifier_list).rwsem){.+.+.+}, at: [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 ((fb_notifier_list).rwsem){.+.+.+}: [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff8175b797>] down_read+0x47/0x5c [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper] [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau] [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau] [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm] [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau] [<ffffffff813b13db>] local_pci_probe+0x4b/0x80 [<ffffffff813b1701>] pci_device_probe+0x111/0x120 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0 [<ffffffff81497bab>] __driver_attach+0xab/0xb0 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0 [<ffffffff814971fe>] driver_attach+0x1e/0x20 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290 [<ffffffff814982b7>] driver_register+0x77/0x170 [<ffffffff813b0454>] __pci_register_driver+0x64/0x70 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm] [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0 [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b -> #1 (console_lock){+.+.+.}: [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff810430a7>] console_lock+0x77/0x80 [<ffffffff8146b2a1>] con_flush_chars+0x31/0x50 [<ffffffff8145780c>] n_tty_write+0x1ec/0x4d0 [<ffffffff814541b9>] tty_write+0x159/0x2e0 [<ffffffff814543f5>] redirected_tty_write+0xb5/0xc0 [<ffffffff811ab9d5>] vfs_write+0xc5/0x1f0 [<ffffffff811abec5>] SyS_write+0x55/0xa0 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b -> #0 (&tty->termios_rwsem){++++..}: [<ffffffff810b65c3>] __lock_acquire+0x1c43/0x1d30 [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff8175b724>] down_write+0x44/0x70 [<ffffffff81452656>] tty_do_resize+0x36/0xe0 [<ffffffff8146c841>] vc_do_resize+0x3e1/0x4c0 [<ffffffff8146c99f>] vc_resize+0x1f/0x30 [<ffffffff813e4535>] fbcon_init+0x385/0x5a0 [<ffffffff8146a4bc>] visual_init+0xbc/0x120 [<ffffffff8146cd13>] do_bind_con_driver+0x163/0x320 [<ffffffff8146cfa1>] do_take_over_console+0x61/0x70 [<ffffffff813e2b93>] do_fbcon_takeover+0x63/0xc0 [<ffffffff813e67a5>] fbcon_event_notify+0x715/0x820 [<ffffffff81762f9d>] notifier_call_chain+0x5d/0x110 [<ffffffff8107aadc>] __blocking_notifier_call_chain+0x6c/0xc0 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper] [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau] [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau] [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm] [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau] [<ffffffff813b13db>] local_pci_probe+0x4b/0x80 [<ffffffff813b1701>] pci_device_probe+0x111/0x120 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0 [<ffffffff81497bab>] __driver_attach+0xab/0xb0 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0 [<ffffffff814971fe>] driver_attach+0x1e/0x20 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290 [<ffffffff814982b7>] driver_register+0x77/0x170 [<ffffffff813b0454>] __pci_register_driver+0x64/0x70 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm] [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0 [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b other info that might help us debug this: Chain exists of: &tty->termios_rwsem --> console_lock --> (fb_notifier_list).rwsem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((fb_notifier_list).rwsem); lock(console_lock); lock((fb_notifier_list).rwsem); lock(&tty->termios_rwsem); *** DEADLOCK *** 7 locks held by modprobe/277: #0: (&__lockdep_no_validate__){......}, at: [<ffffffff81497b5b>] __driver_attach+0x5b/0xb0 #1: (&__lockdep_no_validate__){......}, at: [<ffffffff81497b69>] __driver_attach+0x69/0xb0 #2: (drm_global_mutex){+.+.+.}, at: [<ffffffffa008a6dd>] drm_get_pci_dev+0xbd/0x2a0 [drm] #3: (registration_lock){+.+.+.}, at: [<ffffffff813d93f5>] register_framebuffer+0x25/0x320 #4: (&fb_info->lock){+.+.+.}, at: [<ffffffff813d8116>] lock_fb_info+0x26/0x60 #5: (console_lock){+.+.+.}, at: [<ffffffff813d95a4>] register_framebuffer+0x1d4/0x320 #6: ((fb_notifier_list).rwsem){.+.+.+}, at: [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0 stack backtrace: CPU: 0 PID: 277 Comm: modprobe Not tainted 3.10.0-0+tip-xeon+lockdep #0+tip Hardware name: Dell Inc. Precision WorkStation T5400 /0RW203, BIOS A11 04/30/2012 ffffffff8213e5e0 ffff8802aa2fb298 ffffffff81755f19 ffff8802aa2fb2e8 ffffffff8174f506 ffff8802aa2fa000 ffff8802aa2fb378 ffff8802aa2ea8e8 ffff8802aa2ea910 ffff8802aa2ea8e8 0000000000000006 0000000000000007 Call Trace: [<ffffffff81755f19>] dump_stack+0x19/0x1b [<ffffffff8174f506>] print_circular_bug+0x1fb/0x20c [<ffffffff810b65c3>] __lock_acquire+0x1c43/0x1d30 [<ffffffff810b775e>] ? mark_held_locks+0xae/0x120 [<ffffffff810b78d5>] ? trace_hardirqs_on_caller+0x105/0x1d0 [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0 [<ffffffff81452656>] ? tty_do_resize+0x36/0xe0 [<ffffffff8175b724>] down_write+0x44/0x70 [<ffffffff81452656>] ? tty_do_resize+0x36/0xe0 [<ffffffff81452656>] tty_do_resize+0x36/0xe0 [<ffffffff8146c841>] vc_do_resize+0x3e1/0x4c0 [<ffffffff8146c99f>] vc_resize+0x1f/0x30 [<ffffffff813e4535>] fbcon_init+0x385/0x5a0 [<ffffffff8146a4bc>] visual_init+0xbc/0x120 [<ffffffff8146cd13>] do_bind_con_driver+0x163/0x320 [<ffffffff8146cfa1>] do_take_over_console+0x61/0x70 [<ffffffff813e2b93>] do_fbcon_takeover+0x63/0xc0 [<ffffffff813e67a5>] fbcon_event_notify+0x715/0x820 [<ffffffff81762f9d>] notifier_call_chain+0x5d/0x110 [<ffffffff8107aadc>] __blocking_notifier_call_chain+0x6c/0xc0 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper] [<ffffffff8173cbcb>] ? kmemleak_alloc+0x5b/0xc0 [<ffffffff81198874>] ? kmem_cache_alloc_trace+0x104/0x290 [<ffffffffa01035e1>] ? drm_fb_helper_single_add_all_connectors+0x81/0xf0 [drm_kms_helper] [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau] [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau] [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm] [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau] [<ffffffff8175f162>] ? _raw_spin_unlock_irqrestore+0x42/0x80 [<ffffffff813b13db>] local_pci_probe+0x4b/0x80 [<ffffffff813b1701>] pci_device_probe+0x111/0x120 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0 [<ffffffff81497bab>] __driver_attach+0xab/0xb0 [<ffffffff81497b00>] ? driver_probe_device+0x3a0/0x3a0 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0 [<ffffffff814971fe>] driver_attach+0x1e/0x20 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290 [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffff814982b7>] driver_register+0x77/0x170 [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffff813b0454>] __pci_register_driver+0x64/0x70 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm] [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffffa022a000>] ? 0xffffffffa0229fff [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0 [<ffffffff81399a50>] ? ddebug_proc_open+0xb0/0xb0 [<ffffffff813855ae>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 04:43:51 +08:00
mutex_unlock(&tty->winsize_mutex);
pty: simplify resize We have special case logic for resizing pty/tty pairs. We also have a per driver resize method so for the pty case we should use it. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 21:43:17 +08:00
return 0;
}
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
/**
* pty_start - start() handler
* pty_stop - stop() handler
* @tty: tty being flow-controlled
*
* Propagates the TIOCPKT status to the master pty.
*
* NB: only the master pty can be in packet mode so only the slave
* needs start()/stop() handlers
*/
static void pty_start(struct tty_struct *tty)
{
unsigned long flags;
if (tty->link && tty->link->packet) {
pty: Don't claim slave's ctrl_lock for master's packet mode The slave's ctrl_lock serializes updates to the ctrl_status field only, whereas the master's ctrl_lock serializes updates to the packet mode enable (ie., the master does not have ctrl_status and the slave does not have packet mode). Thus, claiming the slave's ctrl_lock to access ->packet is useless. Unlocked reads of ->packet are already smp-safe. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:26 +08:00
spin_lock_irqsave(&tty->ctrl_lock, flags);
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
tty->ctrl_status &= ~TIOCPKT_STOP;
tty->ctrl_status |= TIOCPKT_START;
pty: Don't claim slave's ctrl_lock for master's packet mode The slave's ctrl_lock serializes updates to the ctrl_status field only, whereas the master's ctrl_lock serializes updates to the packet mode enable (ie., the master does not have ctrl_status and the slave does not have packet mode). Thus, claiming the slave's ctrl_lock to access ->packet is useless. Unlocked reads of ->packet are already smp-safe. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:26 +08:00
spin_unlock_irqrestore(&tty->ctrl_lock, flags);
vfs: do bulk POLL* -> EPOLL* replacement This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-12 06:34:03 +08:00
wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN);
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
}
}
static void pty_stop(struct tty_struct *tty)
{
unsigned long flags;
if (tty->link && tty->link->packet) {
pty: Don't claim slave's ctrl_lock for master's packet mode The slave's ctrl_lock serializes updates to the ctrl_status field only, whereas the master's ctrl_lock serializes updates to the packet mode enable (ie., the master does not have ctrl_status and the slave does not have packet mode). Thus, claiming the slave's ctrl_lock to access ->packet is useless. Unlocked reads of ->packet are already smp-safe. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:26 +08:00
spin_lock_irqsave(&tty->ctrl_lock, flags);
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
tty->ctrl_status &= ~TIOCPKT_START;
tty->ctrl_status |= TIOCPKT_STOP;
pty: Don't claim slave's ctrl_lock for master's packet mode The slave's ctrl_lock serializes updates to the ctrl_status field only, whereas the master's ctrl_lock serializes updates to the packet mode enable (ie., the master does not have ctrl_status and the slave does not have packet mode). Thus, claiming the slave's ctrl_lock to access ->packet is useless. Unlocked reads of ->packet are already smp-safe. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-17 03:33:26 +08:00
spin_unlock_irqrestore(&tty->ctrl_lock, flags);
vfs: do bulk POLL* -> EPOLL* replacement This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-12 06:34:03 +08:00
wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN);
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
}
}
tty: Fix race in tty release Ian Abbott found that the tty layer would explode with the right set of parallel open and close operations. This is because we race in the handling of tty->drivers->termios[]. Correct this by Making tty_ldisc_release behave like nromal code (takes the lock, does stuff, drops the lock) Drop the tty lock earlier in tty_ldisc_release Taking the tty mutex around the driver->termios update in all cases Adding a WARN_ON to catch future screwups. I also forgot to clean up the pty resources properly. With a pty pair we need to pull both halves out of the tables. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-28 01:02:54 +08:00
/**
* pty_common_install - set up the pty pair
* @driver: the pty driver
* @tty: the tty being instantiated
drivers: tty: Merge alloc_tty_struct and initialize_tty_struct The two functions alloc_tty_struct and initialize_tty_struct are always called together. Merge them into alloc_tty_struct, updating its prototype and the only two callers of these functions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 03:01:22 +08:00
* @legacy: true if this is BSD style
tty: Fix race in tty release Ian Abbott found that the tty layer would explode with the right set of parallel open and close operations. This is because we race in the handling of tty->drivers->termios[]. Correct this by Making tty_ldisc_release behave like nromal code (takes the lock, does stuff, drops the lock) Drop the tty lock earlier in tty_ldisc_release Taking the tty mutex around the driver->termios update in all cases Adding a WARN_ON to catch future screwups. I also forgot to clean up the pty resources properly. With a pty pair we need to pull both halves out of the tables. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-28 01:02:54 +08:00
*
* Perform the initial set up for the tty/pty pair. Called from the
* tty layer when the port is first opened.
*
* Locking: the caller must hold the tty_mutex
*/
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
bool legacy)
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
{
struct tty_struct *o_tty;
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
struct tty_port *ports[2];
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
int idx = tty->index;
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
int retval = -ENOMEM;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
pty: Always return -EIO if slave BSD pty opened first Opening the slave BSD pty first already returns -EIO from the slave pty_open(), which in turn causes the newly installed tty pair to be released before returning from tty_open(). However, this can also cause a parallel master BSD pty open to fail because the pty pair destruction may already been taking place in tty_release(). Failing at driver->install() if the slave pty is opened first ensures that a pty master open cannot fail, because the driver tables will not have been updated so tty_driver_lookup_tty() won't find the master pty (and attempt to "re-open" it). In turn, this guarantees that any tty with a tty->count == 0 is in final close (rather than never opened). Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 01:12:49 +08:00
/* Opening the slave first has always returned -EIO */
if (driver->subtype != PTY_TYPE_MASTER)
return -EIO;
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
TTY: pty, stop passing NULL to free_tty_struct In case alloc_tty_struct fails in pty_common_install, we pass NULL to free_tty_struct. This is invalid as the function is not ready to cope with that. And even if it was, it is not nice to do that anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 03:47:26 +08:00
if (!ports[0] || !ports[1])
drivers: tty: Merge alloc_tty_struct and initialize_tty_struct The two functions alloc_tty_struct and initialize_tty_struct are always called together. Merge them into alloc_tty_struct, updating its prototype and the only two callers of these functions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 03:01:22 +08:00
goto err;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
if (!try_module_get(driver->other->owner)) {
/* This cannot in fact currently happen */
drivers: tty: Merge alloc_tty_struct and initialize_tty_struct The two functions alloc_tty_struct and initialize_tty_struct are always called together. Merge them into alloc_tty_struct, updating its prototype and the only two callers of these functions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 03:01:22 +08:00
goto err;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
}
drivers: tty: Merge alloc_tty_struct and initialize_tty_struct The two functions alloc_tty_struct and initialize_tty_struct are always called together. Merge them into alloc_tty_struct, updating its prototype and the only two callers of these functions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 03:01:22 +08:00
o_tty = alloc_tty_struct(driver->other, idx);
if (!o_tty)
goto err_put_module;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
tty: Preset lock subclass for nested tty locks Eliminate the requirement of specifying the tty lock nesting at lock time; instead, set the lock subclass for slave ptys at pty install (normal ttys and master ptys use subclass 0). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 01:13:02 +08:00
tty_set_lock_subclass(o_tty);
n_tty: Fix signal handling flushes BRKINT and ISIG requires input and output flush when a signal char is received. However, the order of operations is significant since parallel i/o may be ongoing. Merge the signal handling for BRKINT with ISIG handling. Process the signal first. This ensures any ongoing i/o is aborted; without this, a waiting writer may continue writing after the flush occurs and after the signal char has been echoed. Write lock the termios_rwsem, which excludes parallel writers from pushing new i/o until after the output buffers are flushed; claiming the write lock is necessary anyway to exclude parallel readers while the read buffer is flushed. Subclass the termios_rwsem for ptys since the slave pty performing the flush may appear to reorder the termios_rwsem->tty buffer lock lock order; adding annotation clarifies that slave tty_buffer lock-> slave termios_rwsem -> master tty_buffer lock is a valid lock order. Flush the echo buffer. In this context, the echo buffer is 'output'. Otherwise, the output will appear discontinuous because the output buffer was cleared which contains older output than the echo buffer. Open-code the read buffer flush since the input worker does not need kicking (this is the input worker). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-18 04:42:06 +08:00
lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
tty: Preset lock subclass for nested tty locks Eliminate the requirement of specifying the tty lock nesting at lock time; instead, set the lock subclass for slave ptys at pty install (normal ttys and master ptys use subclass 0). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 01:13:02 +08:00
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
if (legacy) {
/* We always use new tty termios data so we can do this
the easy way .. */
tty: Fix tty_init_termios() declaration tty_init_termios() never returns an error; re-declare as void. Remove unnecessary error handling from callers. Remove extern declarations of tty_free_termios() and free_tty_struct() and re-declare in file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-10 13:13:48 +08:00
tty_init_termios(tty);
tty_init_termios(o_tty);
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
driver->other->ttys[idx] = o_tty;
driver->ttys[idx] = tty;
} else {
tty: move the termios object into the tty This will let us sort out a whole pile of tty related races. The alternative would be to keep points and refcount the termios objects. However 1. They are tiny anyway 2. Many devices don't use the stored copies 3. We can remove a pty special case Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-14 22:31:47 +08:00
memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
tty->termios = driver->init_termios;
memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
o_tty->termios = driver->other->init_termios;
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
}
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +08:00
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
/*
* Everything allocated ... set up the o_tty structure.
*/
tty_driver_kref_get(driver->other);
/* Establish the links in both directions */
tty->link = o_tty;
o_tty->link = tty;
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
tty_port_init(ports[0]);
tty_port_init(ports[1]);
pty: Fix overlimit memory use The pty_space() computation is broken; the space already consumed in the tty buffer is not accounted for. Use tty_buffer_set_limit(), which enforces the limit automatically. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-17 04:22:14 +08:00
tty_buffer_set_limit(ports[0], 8192);
tty_buffer_set_limit(ports[1], 8192);
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
o_tty->port = ports[0];
tty->port = ports[1];
TTY: add port -> tty link For that purpose we have to temporarily introduce a second tty back pointer into tty_port. It is because serial layer, and maybe others, still do not use tty_port_tty_set/get. So that we cannot set the tty_port->tty to NULL at will now. Yes, the fix would be to convert whole serial layer and all its users to tty_port_tty_set/get. However we are in the process of removing the need of tty in most of the call sites, so this would lead to a duplicated work. Instead we have now tty_port->itty (internal tty) which will be used only in flush_to_ldisc. For that one it is ensured that itty is valid wherever the work is run. IOW, the work is synchronously cancelled before we set itty to NULL and also before hangup is processed. After we need only tty_port and not tty_struct in most code, this shall be changed to tty_port_tty_set/get and itty removed completely. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-19 04:26:46 +08:00
o_tty->port->itty = o_tty;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
pty: Fix buffer flush deadlock The pty driver does not clear its write buffer when commanded. This is to avoid an apparent deadlock between parallel flushes from both pty ends; specifically when handling either BRK or INTR input. However, parallel flushes from this source is not possible since the pty master can never be set to BRKINT or ISIG. Parallel flushes from other sources are possible but these do not threaten deadlocks. Annotate the tty buffer mutex for lockdep to represent the nested tty_buffer locking which occurs when the pty slave is processing input (its buffer mutex held) and receives INTR or BRK and acquires the linked tty buffer mutex via tty_buffer_flush(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-18 04:42:05 +08:00
tty_buffer_set_lock_subclass(o_tty->port);
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
tty_driver_kref_get(driver);
tty->count++;
pty: Always return -EIO if slave BSD pty opened first Opening the slave BSD pty first already returns -EIO from the slave pty_open(), which in turn causes the newly installed tty pair to be released before returning from tty_open(). However, this can also cause a parallel master BSD pty open to fail because the pty pair destruction may already been taking place in tty_release(). Failing at driver->install() if the slave pty is opened first ensures that a pty master open cannot fail, because the driver tables will not have been updated so tty_driver_lookup_tty() won't find the master pty (and attempt to "re-open" it). In turn, this guarantees that any tty with a tty->count == 0 is in final close (rather than never opened). Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 01:12:49 +08:00
o_tty->count++;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
return 0;
tty: Fix tty_init_termios() declaration tty_init_termios() never returns an error; re-declare as void. Remove unnecessary error handling from callers. Remove extern declarations of tty_free_termios() and free_tty_struct() and re-declare in file scope. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-10 13:13:48 +08:00
drivers: tty: Merge alloc_tty_struct and initialize_tty_struct The two functions alloc_tty_struct and initialize_tty_struct are always called together. Merge them into alloc_tty_struct, updating its prototype and the only two callers of these functions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 03:01:22 +08:00
err_put_module:
drivers: tty: Fix use-after-free in pty_common_install In 2c964a2f "drivers: tty: Merge alloc_tty_struct and initialize_tty_struct", I messed up the refactorization of pty_common_install, causing use-after-free and NULL pointer derefs on various error paths. This should fix it. Reported-by: Julia Lawall <julia.lawall@lip6.fr> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-13 07:44:00 +08:00
module_put(driver->other->owner);
drivers: tty: Merge alloc_tty_struct and initialize_tty_struct The two functions alloc_tty_struct and initialize_tty_struct are always called together. Merge them into alloc_tty_struct, updating its prototype and the only two callers of these functions. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-11 03:01:22 +08:00
err:
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
kfree(ports[0]);
kfree(ports[1]);
TTY: unify pty_install fail path handling Change it so that we call the deinit functions at one place at the end of the function (by gotos). And while at it use some sane label names. This is a preparation for the deinitialization of tty in the next patch. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-23 17:48:33 +08:00
return retval;
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
}
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
static void pty_cleanup(struct tty_struct *tty)
{
TTY: pty, fix tty buffers leak After commit "TTY: move tty buffers to tty_port", the tty buffers are not freed in some drivers. This is because tty_port_destructor is not called whenever a tty_port is freed. This was an assumption I counted with but was unfortunately untrue. So fix the drivers to fulfil this assumption. PTY is one of those, here we just need to use tty_port_put instead of kfree. (Assuming tty_port_destructor does not need port->ops to be set which we change here too.) Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15 16:49:49 +08:00
tty_port_put(tty->port);
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
}
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
/* Traditional BSD devices */
#ifdef CONFIG_LEGACY_PTYS
static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
{
return pty_common_install(driver, tty, true);
}
tty: Fix race in tty release Ian Abbott found that the tty layer would explode with the right set of parallel open and close operations. This is because we race in the handling of tty->drivers->termios[]. Correct this by Making tty_ldisc_release behave like nromal code (takes the lock, does stuff, drops the lock) Drop the tty lock earlier in tty_ldisc_release Taking the tty mutex around the driver->termios update in all cases Adding a WARN_ON to catch future screwups. I also forgot to clean up the pty resources properly. With a pty pair we need to pull both halves out of the tables. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-28 01:02:54 +08:00
static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
{
struct tty_struct *pair = tty->link;
driver->ttys[tty->index] = NULL;
if (pair)
pair->driver->ttys[pair->index] = NULL;
}
tty: now phase out the ioctl file pointer for good Only oddities here are a couple of drivers that bogusly called the ldisc helpers instead of returning -ENOIOCTLCMD. Fix the bug and the rest goes away. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-15 00:27:22 +08:00
static int pty_bsd_ioctl(struct tty_struct *tty,
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
unsigned int cmd, unsigned long arg)
{
switch (cmd) {
case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
return pty_set_lock(tty, (int __user *) arg);
tty: Add get- ioctls to fetch tty status v3 For checkpoint/restore we need to know if tty has exclusive or packet mode set, as well as if pty is currently locked. Just to be able to restore this characteristics. For this sake the following ioctl codes are introduced - TIOCGPKT to get packet mode state - TIOCGPTLCK to get Pty locked state - TIOCGEXCL to get Exclusive mode state Note this ioctls are a bit unsafe in terms of data obtained consistency. The tty characteristics might be changed right after ioctl complete. Keep it in mind and use this ioctl carefully. v2: - Use TIOC prefix for ioctl codes (by jslaby@) Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Alan Cox <alan@lxorguk.ukuu.org.uk> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:22 +08:00
case TIOCGPTLCK: /* Get PT Lock status */
return pty_get_lock(tty, (int __user *)arg);
tty: pty - Move TIOCPKT handling into pty.c Since this ioctl is for pty devices only move it to pty.c. v2: - drop PTY_TYPE_MASTER test since it's master peer ioctl anyway (by jslaby@) Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:20 +08:00
case TIOCPKT: /* Set PT packet mode */
return pty_set_pktmode(tty, (int __user *)arg);
tty: Add get- ioctls to fetch tty status v3 For checkpoint/restore we need to know if tty has exclusive or packet mode set, as well as if pty is currently locked. Just to be able to restore this characteristics. For this sake the following ioctl codes are introduced - TIOCGPKT to get packet mode state - TIOCGPTLCK to get Pty locked state - TIOCGEXCL to get Exclusive mode state Note this ioctls are a bit unsafe in terms of data obtained consistency. The tty characteristics might be changed right after ioctl complete. Keep it in mind and use this ioctl carefully. v2: - Use TIOC prefix for ioctl codes (by jslaby@) Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Alan Cox <alan@lxorguk.ukuu.org.uk> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:22 +08:00
case TIOCGPKT: /* Get PT packet mode */
return pty_get_pktmode(tty, (int __user *)arg);
tty: Add EXTPROC support for LINEMODE This patch is against the 2.6.34 source. Paraphrased from the 1989 BSD patch by David Borman @ cray.com: These are the changes needed for the kernel to support LINEMODE in the server. There is a new bit in the termios local flag word, EXTPROC. When this bit is set, several aspects of the terminal driver are disabled. Input line editing, character echo, and mapping of signals are all disabled. This allows the telnetd to turn off these functions when in linemode, but still keep track of what state the user wants the terminal to be in. New ioctl: TIOCSIG Generate a signal to processes in the current process group of the pty. There is a new mode for packet driver, the TIOCPKT_IOCTL bit. When packet mode is turned on in the pty, and the EXTPROC bit is set, then whenever the state of the pty is changed, the next read on the master side of the pty will have the TIOCPKT_IOCTL bit set. This allows the process on the server side of the pty to know when the state of the terminal has changed; it can then issue the appropriate ioctl to retrieve the new state. Since the original BSD patches accompanied the source code for telnet I've left that reference here, but obviously the feature is useful for any remote terminal protocol, including ssh. The corresponding feature has existed in the BSD tty driver since 1989. For historical reference, a good copy of the relevant files can be found here: http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741 Signed-off-by: Howard Chu <hyc@symas.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-23 01:14:49 +08:00
case TIOCSIG: /* Send signal to other side of pty */
return pty_signal(tty, (int) arg);
pty: return EINVAL for TIOCGPTN for BSD ptys Commit bbb63c514a3464342967237a51a21ea8f61ab951 (drivers:tty:fix up ENOIOCTLCMD error handling) changed the default return value from tty ioctl to be ENOTTY and not EINVAL. This is appropriate. But in case of TIOCGPTN for the old BSD ptys glibc started failing because it expects EINVAL to be returned. Only then it continues to obtain the pts name the other way around. So fix this case by explicit return of EINVAL in this case. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Florian Westphal <fw@strlen.de> Cc: Alan Cox <alan@linux.intel.com> Cc: stable <stable@vger.kernel.org> # 3.7+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-11 19:06:27 +08:00
case TIOCGPTN: /* TTY returns ENOTTY, but glibc expects EINVAL here */
return -EINVAL;
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 -ENOIOCTLCMD;
}
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
#ifdef CONFIG_COMPAT
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
static long pty_bsd_compat_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
/*
* PTY ioctls don't require any special translation between 32-bit and
* 64-bit userspace, they are already compatible.
*/
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
return pty_bsd_ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
}
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
#else
#define pty_bsd_compat_ioctl NULL
#endif
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
PTY: add kernel parameter to overwrite legacy pty count Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-15 18:25:38 +08:00
static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
drivers/tty: make pty.c slightly more explicitly non-modular The Kconfig currently controlling compilation of this code is: drivers/tty/Kconfig:config LEGACY_PTYS drivers/tty/Kconfig: bool "Legacy (BSD) PTY support" ...and: drivers/tty/Kconfig:config UNIX98_PTYS drivers/tty/Kconfig: bool "Unix98 PTY support" if EXPERT combined with this: obj-$(CONFIG_LEGACY_PTYS) += pty.o obj-$(CONFIG_UNIX98_PTYS) += pty.o ...meaning that it currently is not being built as a module by anyone. Lets remove the traces of modularity we can so that when reading the driver there is less doubt it is builtin-only. Since module_init translates to device_initcall in the non-modular case, the init ordering remains unchanged with this commit. We don't delete the module.h include since other parts of the file are using content from there. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-20 05:48:05 +08:00
/*
* not really modular, but the easiest way to keep compat with existing
* bootargs behaviour is to continue using module_param here.
*/
PTY: add kernel parameter to overwrite legacy pty count Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-15 18:25:38 +08:00
module_param(legacy_count, int, 0);
pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells <dhowells@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-30 22:49:40 +08:00
/*
* The master side of a pty can do TIOCSPTLCK and thus
* has pty_bsd_ioctl.
*/
static const struct tty_operations master_pty_ops_bsd = {
.install = pty_install,
pty: prepare for tty->ops changes We are about to change the tty layer to avoid keeping private copies of all the methods in each tty. We have to update the pty layer first as it currently patches the ioctl method according to the tty type. Use multiple tty operations sets instead. Signed-off-by: Alan Cox <alan@redhat.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 15:54:10 +08:00
.open = pty_open,
.close = pty_close,
.write = pty_write,
.write_room = pty_write_room,
.flush_buffer = pty_flush_buffer,
.chars_in_buffer = pty_chars_in_buffer,
.unthrottle = pty_unthrottle,
.ioctl = pty_bsd_ioctl,
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
.compat_ioctl = pty_bsd_compat_ioctl,
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
.cleanup = pty_cleanup,
tty: Fix race in tty release Ian Abbott found that the tty layer would explode with the right set of parallel open and close operations. This is because we race in the handling of tty->drivers->termios[]. Correct this by Making tty_ldisc_release behave like nromal code (takes the lock, does stuff, drops the lock) Drop the tty lock earlier in tty_ldisc_release Taking the tty mutex around the driver->termios update in all cases Adding a WARN_ON to catch future screwups. I also forgot to clean up the pty resources properly. With a pty pair we need to pull both halves out of the tables. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-28 01:02:54 +08:00
.resize = pty_resize,
.remove = pty_remove
pty: prepare for tty->ops changes We are about to change the tty layer to avoid keeping private copies of all the methods in each tty. We have to update the pty layer first as it currently patches the ioctl method according to the tty type. Use multiple tty operations sets instead. Signed-off-by: Alan Cox <alan@redhat.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 15:54:10 +08:00
};
pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells <dhowells@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-30 22:49:40 +08:00
static const struct tty_operations slave_pty_ops_bsd = {
.install = pty_install,
.open = pty_open,
.close = pty_close,
.write = pty_write,
.write_room = pty_write_room,
.flush_buffer = pty_flush_buffer,
.chars_in_buffer = pty_chars_in_buffer,
.unthrottle = pty_unthrottle,
.set_termios = pty_set_termios,
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
.cleanup = pty_cleanup,
tty: Fix race in tty release Ian Abbott found that the tty layer would explode with the right set of parallel open and close operations. This is because we race in the handling of tty->drivers->termios[]. Correct this by Making tty_ldisc_release behave like nromal code (takes the lock, does stuff, drops the lock) Drop the tty lock earlier in tty_ldisc_release Taking the tty mutex around the driver->termios update in all cases Adding a WARN_ON to catch future screwups. I also forgot to clean up the pty resources properly. With a pty pair we need to pull both halves out of the tables. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-28 01:02:54 +08:00
.resize = pty_resize,
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
.start = pty_start,
.stop = pty_stop,
tty: Fix race in tty release Ian Abbott found that the tty layer would explode with the right set of parallel open and close operations. This is because we race in the handling of tty->drivers->termios[]. Correct this by Making tty_ldisc_release behave like nromal code (takes the lock, does stuff, drops the lock) Drop the tty lock earlier in tty_ldisc_release Taking the tty mutex around the driver->termios update in all cases Adding a WARN_ON to catch future screwups. I also forgot to clean up the pty resources properly. With a pty pair we need to pull both halves out of the tables. Signed-off-by: Alan Cox <alan@linux.intel.com> Tested-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-28 01:02:54 +08:00
.remove = pty_remove
pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells <dhowells@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-30 22:49:40 +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
static void __init legacy_pty_init(void)
{
pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells <dhowells@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-30 22:49:40 +08:00
struct tty_driver *pty_driver, *pty_slave_driver;
PTY: add kernel parameter to overwrite legacy pty count Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-15 18:25:38 +08:00
if (legacy_count <= 0)
return;
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
TTY: pty, switch to tty_alloc_driver Switch to the new driver allocation interface, as this is one of the special call-sites. Here, we need TTY_DRIVER_DYNAMIC_ALLOC to not allocate tty_driver->ports, cdevs and potentially other structures because we reserve too many lines in pty. Instead, it provides the tty_port<->tty_struct link in tty->ops->install already. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-09 04:26:41 +08:00
pty_driver = tty_alloc_driver(legacy_count,
TTY_DRIVER_RESET_TERMIOS |
TTY_DRIVER_REAL_RAW |
TTY_DRIVER_DYNAMIC_ALLOC);
TTY: tty_alloc_driver() returns error pointers We changed these from alloc_tty_driver() to tty_alloc_driver() so the error handling needs to modified to check for IS_ERR() instead of NULL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 21:16:56 +08:00
if (IS_ERR(pty_driver))
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
panic("Couldn't allocate pty driver");
TTY: pty, switch to tty_alloc_driver Switch to the new driver allocation interface, as this is one of the special call-sites. Here, we need TTY_DRIVER_DYNAMIC_ALLOC to not allocate tty_driver->ports, cdevs and potentially other structures because we reserve too many lines in pty. Instead, it provides the tty_port<->tty_struct link in tty->ops->install already. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-09 04:26:41 +08:00
pty_slave_driver = tty_alloc_driver(legacy_count,
TTY_DRIVER_RESET_TERMIOS |
TTY_DRIVER_REAL_RAW |
TTY_DRIVER_DYNAMIC_ALLOC);
TTY: tty_alloc_driver() returns error pointers We changed these from alloc_tty_driver() to tty_alloc_driver() so the error handling needs to modified to check for IS_ERR() instead of NULL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 21:16:56 +08:00
if (IS_ERR(pty_slave_driver))
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
panic("Couldn't allocate pty slave driver");
pty_driver->driver_name = "pty_master";
pty_driver->name = "pty";
pty_driver->major = PTY_MASTER_MAJOR;
pty_driver->minor_start = 0;
pty_driver->type = TTY_DRIVER_TYPE_PTY;
pty_driver->subtype = PTY_TYPE_MASTER;
pty_driver->init_termios = tty_std_termios;
pty_driver->init_termios.c_iflag = 0;
pty_driver->init_termios.c_oflag = 0;
pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
pty_driver->init_termios.c_lflag = 0;
[PATCH] tty: switch to ktermios This is the grungy swap all the occurrences in the right places patch that goes with the updates. At this point we have the same functionality as before (except that sgttyb() returns speeds not zero) and are ready to begin turning new stuff on providing nobody reports lots of bugs If you are a tty driver author converting an out of tree driver the only impact should be termios->ktermios name changes for the speed/property setting functions from your upper layers. If you are implementing your own TCGETS function before then your driver was broken already and its about to get a whole lot more painful for you so please fix it 8) Also fill in c_ispeed/ospeed on init for most devices, although the current code will do this for you anyway but I'd like eventually to lose that extra paranoia [akpm@osdl.org: bluetooth fix] [mp3@de.ibm.com: sclp fix] [mp3@de.ibm.com: warning fix for tty3270] [hugh@veritas.com: fix tty_ioctl powerpc build] [jdike@addtoit.com: uml: fix ->set_termios declaration] Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 18:38:45 +08:00
pty_driver->init_termios.c_ispeed = 38400;
pty_driver->init_termios.c_ospeed = 38400;
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
pty_driver->other = pty_slave_driver;
pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells <dhowells@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-30 22:49:40 +08:00
tty_set_operations(pty_driver, &master_pty_ops_bsd);
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
pty_slave_driver->driver_name = "pty_slave";
pty_slave_driver->name = "ttyp";
pty_slave_driver->major = PTY_SLAVE_MAJOR;
pty_slave_driver->minor_start = 0;
pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
pty_slave_driver->subtype = PTY_TYPE_SLAVE;
pty_slave_driver->init_termios = tty_std_termios;
pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
[PATCH] tty: switch to ktermios This is the grungy swap all the occurrences in the right places patch that goes with the updates. At this point we have the same functionality as before (except that sgttyb() returns speeds not zero) and are ready to begin turning new stuff on providing nobody reports lots of bugs If you are a tty driver author converting an out of tree driver the only impact should be termios->ktermios name changes for the speed/property setting functions from your upper layers. If you are implementing your own TCGETS function before then your driver was broken already and its about to get a whole lot more painful for you so please fix it 8) Also fill in c_ispeed/ospeed on init for most devices, although the current code will do this for you anyway but I'd like eventually to lose that extra paranoia [akpm@osdl.org: bluetooth fix] [mp3@de.ibm.com: sclp fix] [mp3@de.ibm.com: warning fix for tty3270] [hugh@veritas.com: fix tty_ioctl powerpc build] [jdike@addtoit.com: uml: fix ->set_termios declaration] Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 18:38:45 +08:00
pty_slave_driver->init_termios.c_ispeed = 38400;
pty_slave_driver->init_termios.c_ospeed = 38400;
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
pty_slave_driver->other = pty_driver;
pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells <dhowells@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-30 22:49:40 +08:00
tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
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 (tty_register_driver(pty_driver))
panic("Couldn't register pty driver");
if (tty_register_driver(pty_slave_driver))
panic("Couldn't register pty slave driver");
}
#else
static inline void legacy_pty_init(void) { }
#endif
/* Unix98 devices */
#ifdef CONFIG_UNIX98_PTYS
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
static struct cdev ptmx_cdev;
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
/**
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
* ptm_open_peer - open the peer of a pty
* @master: the open struct file of the ptmx device node
* @tty: the master of the pty being opened
* @flags: the flags for open
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
*
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
* Provide a race free way for userspace to open the slave end of a pty
* (where they have the master fd and cannot access or trust the mount
* namespace /dev/pts was mounted inside).
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
*/
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
int ptm_open_peer(struct file *master, struct tty_struct *tty, int flags)
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
{
int fd = -1;
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
struct file *filp;
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
int retval = -EINVAL;
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
struct path path;
if (tty->driver != ptm_driver)
return -EIO;
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
pty: fix O_CLOEXEC for TIOCGPTPEER It was being ignored because the flags were not passed to fd allocation. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Matthijs van Duin <matthijsvanduin@gmail.com> Acked-by: Aleksa Sarai <asarai@suse.de> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-19 16:43:46 +08:00
fd = get_unused_fd_flags(flags);
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
if (fd < 0) {
retval = fd;
goto err;
}
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
/* Compute the slave's path */
path.mnt = devpts_mntget(master, tty->driver_data);
if (IS_ERR(path.mnt)) {
retval = PTR_ERR(path.mnt);
goto err_put;
}
path.dentry = tty->link->driver_data;
filp = dentry_open(&path, flags, current_cred());
mntput(path.mnt);
tty: hide unused pty_get_peer function TIOCGPTPEER is only used for unix98 PTYs, and we get a warning when those are disabled: drivers/tty/pty.c:466:12: error: 'pty_get_peer' defined but not used [-Werror=unused-function] This moves the respective functions inside of the existing #ifdef. Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-21 04:34:13 +08:00
if (IS_ERR(filp)) {
retval = PTR_ERR(filp);
goto err_put;
}
fd_install(fd, filp);
return fd;
err_put:
put_unused_fd(fd);
err:
return retval;
}
tty: now phase out the ioctl file pointer for good Only oddities here are a couple of drivers that bogusly called the ldisc helpers instead of returning -ENOIOCTLCMD. Fix the bug and the rest goes away. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-15 00:27:22 +08:00
static int pty_unix98_ioctl(struct tty_struct *tty,
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
unsigned int cmd, unsigned long arg)
{
switch (cmd) {
case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
return pty_set_lock(tty, (int __user *)arg);
tty: Add get- ioctls to fetch tty status v3 For checkpoint/restore we need to know if tty has exclusive or packet mode set, as well as if pty is currently locked. Just to be able to restore this characteristics. For this sake the following ioctl codes are introduced - TIOCGPKT to get packet mode state - TIOCGPTLCK to get Pty locked state - TIOCGEXCL to get Exclusive mode state Note this ioctls are a bit unsafe in terms of data obtained consistency. The tty characteristics might be changed right after ioctl complete. Keep it in mind and use this ioctl carefully. v2: - Use TIOC prefix for ioctl codes (by jslaby@) Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Alan Cox <alan@lxorguk.ukuu.org.uk> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:22 +08:00
case TIOCGPTLCK: /* Get PT Lock status */
return pty_get_lock(tty, (int __user *)arg);
tty: pty - Move TIOCPKT handling into pty.c Since this ioctl is for pty devices only move it to pty.c. v2: - drop PTY_TYPE_MASTER test since it's master peer ioctl anyway (by jslaby@) Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:20 +08:00
case TIOCPKT: /* Set PT packet mode */
return pty_set_pktmode(tty, (int __user *)arg);
tty: Add get- ioctls to fetch tty status v3 For checkpoint/restore we need to know if tty has exclusive or packet mode set, as well as if pty is currently locked. Just to be able to restore this characteristics. For this sake the following ioctl codes are introduced - TIOCGPKT to get packet mode state - TIOCGPTLCK to get Pty locked state - TIOCGEXCL to get Exclusive mode state Note this ioctls are a bit unsafe in terms of data obtained consistency. The tty characteristics might be changed right after ioctl complete. Keep it in mind and use this ioctl carefully. v2: - Use TIOC prefix for ioctl codes (by jslaby@) Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Alan Cox <alan@lxorguk.ukuu.org.uk> CC: "H. Peter Anvin" <hpa@zytor.com> CC: Pavel Emelyanov <xemul@parallels.com> CC: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 03:43:22 +08:00
case TIOCGPKT: /* Get PT packet mode */
return pty_get_pktmode(tty, (int __user *)arg);
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 TIOCGPTN: /* Get PT Number */
return put_user(tty->index, (unsigned int __user *)arg);
tty: Add EXTPROC support for LINEMODE This patch is against the 2.6.34 source. Paraphrased from the 1989 BSD patch by David Borman @ cray.com: These are the changes needed for the kernel to support LINEMODE in the server. There is a new bit in the termios local flag word, EXTPROC. When this bit is set, several aspects of the terminal driver are disabled. Input line editing, character echo, and mapping of signals are all disabled. This allows the telnetd to turn off these functions when in linemode, but still keep track of what state the user wants the terminal to be in. New ioctl: TIOCSIG Generate a signal to processes in the current process group of the pty. There is a new mode for packet driver, the TIOCPKT_IOCTL bit. When packet mode is turned on in the pty, and the EXTPROC bit is set, then whenever the state of the pty is changed, the next read on the master side of the pty will have the TIOCPKT_IOCTL bit set. This allows the process on the server side of the pty to know when the state of the terminal has changed; it can then issue the appropriate ioctl to retrieve the new state. Since the original BSD patches accompanied the source code for telnet I've left that reference here, but obviously the feature is useful for any remote terminal protocol, including ssh. The corresponding feature has existed in the BSD tty driver since 1989. For historical reference, a good copy of the relevant files can be found here: http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741 Signed-off-by: Howard Chu <hyc@symas.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-23 01:14:49 +08:00
case TIOCSIG: /* Send signal to other side of pty */
return pty_signal(tty, (int) arg);
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 -ENOIOCTLCMD;
}
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
#ifdef CONFIG_COMPAT
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
static long pty_unix98_compat_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
/*
* PTY ioctls don't require any special translation between 32-bit and
* 64-bit userspace, they are already compatible.
*/
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
return pty_unix98_ioctl(tty, cmd,
cmd == TIOCSIG ? arg : (unsigned long)compat_ptr(arg));
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
}
pty: fix compat ioctls pointer-taking ones need compat_ptr(); int-taking one doesn't. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-13 08:53:46 +08:00
#else
#define pty_unix98_compat_ioctl NULL
#endif
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
/**
* ptm_unix98_lookup - find a pty master
* @driver: ptm driver
* @idx: tty index
*
* Look up a pty master device. Called under the tty_mutex for now.
* This provides our locking.
*/
Add an instance parameter devpts interfaces Pass-in 'inode' or 'tty' parameter to devpts interfaces. With multiple devpts instances, these parameters will be used in subsequent patches to identify the instance of devpts mounted. The parameters also help simplify devpts implementation. Changelog[v3]: - minor changes due to merge with ttydev updates - rename parameters to emphasize they are ptmx or pts inodes - pass-in tty_struct * to devpts_pty_kill() (this will help cleanup the get_node() call in a subsequent patch) Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:59 +08:00
static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
devpts: more pty driver interface cleanups This is more prep-work for the upcoming pty changes. Still just code cleanup with no actual semantic changes. This removes a bunch pointless complexity by just having the slave pty side remember the dentry associated with the devpts slave rather than the inode. That allows us to remove all the "look up the dentry" code for when we want to remove it again. Together with moving the tty pointer from "inode->i_private" to "dentry->d_fsdata" and getting rid of pointless inode locking, this removes about 30 lines of code. Not only is the end result smaller, it's simpler and easier to understand. The old code, for example, depended on the d_find_alias() to not just find the dentry, but also to check that it is still hashed, which in turn validated the tty pointer in the inode. That is a _very_ roundabout way to say "invalidate the cached tty pointer when the dentry is removed". The new code just does dentry->d_fsdata = NULL; in devpts_pty_kill() instead, invalidating the tty pointer rather more directly and obviously. Don't do something complex and subtle when the obvious straightforward approach will do. The rest of the patch (ie apart from code deletion and the above tty pointer clearing) is just switching the calling convention to pass the dentry or file pointer around instead of the inode. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-26 11:04:08 +08:00
struct file *file, int idx)
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
{
tty: cleanup prohibition of direct opening for unix98 pty master cleanup hack added in v2.6.27-3203-g15582d3 comment from that patch: : pty: If the administrator creates a device for a ptmx slave we should not error : : The open path for ptmx slaves is via the ptmx device. Opening them any : other way is not allowed. Vegard Nossum found that previously this was not : the case and mknod foo c 128 42; cat foo would produce nasty diagnostics : : Signed-off-by: Alan Cox <alan@redhat.com> : Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> devpts_get_tty() returns non-null only for inodes on devpts, but there is no inodes for master-devices, /dev/ptmx (/dev/pts/ptmx) is the only way to open them. Thus we can completely forbid lookup for master-devices and eliminate that hack in tty_init_dev() because tty_open() will get EIO from tty_driver_lookup_tty(). Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-05 17:04:21 +08:00
/* Master must be open via /dev/ptmx */
return ERR_PTR(-EIO);
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
}
/**
* pts_unix98_lookup - find a pty slave
* @driver: pts driver
* @idx: tty index
*
* Look up a pty master device. Called under the tty_mutex for now.
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
* This provides our locking for the tty pointer.
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
*/
Add an instance parameter devpts interfaces Pass-in 'inode' or 'tty' parameter to devpts interfaces. With multiple devpts instances, these parameters will be used in subsequent patches to identify the instance of devpts mounted. The parameters also help simplify devpts implementation. Changelog[v3]: - minor changes due to merge with ttydev updates - rename parameters to emphasize they are ptmx or pts inodes - pass-in tty_struct * to devpts_pty_kill() (this will help cleanup the get_node() call in a subsequent patch) Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:59 +08:00
static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
devpts: more pty driver interface cleanups This is more prep-work for the upcoming pty changes. Still just code cleanup with no actual semantic changes. This removes a bunch pointless complexity by just having the slave pty side remember the dentry associated with the devpts slave rather than the inode. That allows us to remove all the "look up the dentry" code for when we want to remove it again. Together with moving the tty pointer from "inode->i_private" to "dentry->d_fsdata" and getting rid of pointless inode locking, this removes about 30 lines of code. Not only is the end result smaller, it's simpler and easier to understand. The old code, for example, depended on the d_find_alias() to not just find the dentry, but also to check that it is still hashed, which in turn validated the tty pointer in the inode. That is a _very_ roundabout way to say "invalidate the cached tty pointer when the dentry is removed". The new code just does dentry->d_fsdata = NULL; in devpts_pty_kill() instead, invalidating the tty pointer rather more directly and obviously. Don't do something complex and subtle when the obvious straightforward approach will do. The rest of the patch (ie apart from code deletion and the above tty pointer clearing) is just switching the calling convention to pass the dentry or file pointer around instead of the inode. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-26 11:04:08 +08:00
struct file *file, int idx)
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
{
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
struct tty_struct *tty;
mutex_lock(&devpts_mutex);
devpts: more pty driver interface cleanups This is more prep-work for the upcoming pty changes. Still just code cleanup with no actual semantic changes. This removes a bunch pointless complexity by just having the slave pty side remember the dentry associated with the devpts slave rather than the inode. That allows us to remove all the "look up the dentry" code for when we want to remove it again. Together with moving the tty pointer from "inode->i_private" to "dentry->d_fsdata" and getting rid of pointless inode locking, this removes about 30 lines of code. Not only is the end result smaller, it's simpler and easier to understand. The old code, for example, depended on the d_find_alias() to not just find the dentry, but also to check that it is still hashed, which in turn validated the tty pointer in the inode. That is a _very_ roundabout way to say "invalidate the cached tty pointer when the dentry is removed". The new code just does dentry->d_fsdata = NULL; in devpts_pty_kill() instead, invalidating the tty pointer rather more directly and obviously. Don't do something complex and subtle when the obvious straightforward approach will do. The rest of the patch (ie apart from code deletion and the above tty pointer clearing) is just switching the calling convention to pass the dentry or file pointer around instead of the inode. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-26 11:04:08 +08:00
tty = devpts_get_priv(file->f_path.dentry);
pty: Lock the devpts bits privately This is a private pty affair, we don't want to tangle it with the tty_lock any more as we know all the other non tty locking is now handled by the vfs so we too can move. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 05:22:09 +08:00
mutex_unlock(&devpts_mutex);
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
/* Master must be open before slave */
if (!tty)
return ERR_PTR(-EIO);
return tty;
}
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
tty: More driver operations We have the lookup operation abstracted which is nice for pty cleanup but we really want to abstract the add/remove entries as well so that we can pull the pty code out of the tty core and create a clear defined interface for the tty driver table. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:19 +08:00
{
PTY: merge pty_install implementations There are currently two instances of code which handles PTY install. One for the legacy BSD PTY's, one for unix98's PTY's. Both of them are very similar and differ only in termios allocation and handling. Since we will need to allocate a tty_port at that place, this would require editing two places with the same pattern. Instead, let us move the implementation to one common place and call it from both places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:29 +08:00
return pty_common_install(driver, tty, false);
tty: More driver operations We have the lookup operation abstracted which is nice for pty cleanup but we really want to abstract the add/remove entries as well so that we can pull the pty code out of the tty core and create a clear defined interface for the tty driver table. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:19 +08:00
}
TTY: pty, fix compilation warning When CONFIG_UNIX98_PTYS is unset, we see this warning in pty: drivers/tty/pty.c:409:13: warning: ‘pty_unix98_shutdown’ defined but not used Fix that by moving the function to a section which depends on that config. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Toralf Foerster <toralf.foerster@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-15 13:52:05 +08:00
/* this is called once with whichever end is closed last */
pty: Remove pty_unix98_shutdown() The tty core invokes the optional driver shutdown() just before the optional driver remove() (shutdown() has access to the termios and remove() does not). Because pty drivers must prevent the default remove() action, the Unix98 pty drivers define a dummy remove() function. Instead, release the slave index in the remove() method and delete the optional shutdown() method. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-10 13:13:50 +08:00
static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
TTY: pty, fix compilation warning When CONFIG_UNIX98_PTYS is unset, we see this warning in pty: drivers/tty/pty.c:409:13: warning: ‘pty_unix98_shutdown’ defined but not used Fix that by moving the function to a section which depends on that config. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Toralf Foerster <toralf.foerster@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-15 13:52:05 +08:00
{
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
struct pts_fs_info *fsi;
pty: fix possible use after free of tty->driver_data This change fixes a bug for a corner case where we have the the last release from a pty master/slave coming from a previously opened /dev/tty file. When this happens, the tty->driver_data can be stale, due to all ptmx or pts/N files having already been closed before (and thus the inode related to these files, which tty->driver_data points to, being already freed/destroyed). The fix here is to keep a reference on the opened master ptmx inode. We maintain the inode referenced until the final pty_unix98_shutdown, and only pass this inode to devpts_kill_index. Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: <stable@vger.kernel.org> # 2.6.29+ Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-11 22:07:43 +08:00
if (tty->driver->subtype == PTY_TYPE_MASTER)
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
fsi = tty->driver_data;
pty: fix possible use after free of tty->driver_data This change fixes a bug for a corner case where we have the the last release from a pty master/slave coming from a previously opened /dev/tty file. When this happens, the tty->driver_data can be stale, due to all ptmx or pts/N files having already been closed before (and thus the inode related to these files, which tty->driver_data points to, being already freed/destroyed). The fix here is to keep a reference on the opened master ptmx inode. We maintain the inode referenced until the final pty_unix98_shutdown, and only pass this inode to devpts_kill_index. Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: <stable@vger.kernel.org> # 2.6.29+ Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-11 22:07:43 +08:00
else
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
fsi = tty->link->driver_data;
devpts: fix null pointer dereference on failed memory allocation An ENOMEM when creating a pair tty in tty_ldisc_setup causes a null pointer dereference in devpts_kill_index because tty->link->driver_data is NULL. The oops was triggered with the pty stressor in stress-ng when in a low memory condition. tty_init_dev tries to clean up a tty_ldisc_setup ENOMEM error by calling release_tty, however, this ultimately tries to clean up the NULL pair'd tty in pty_unix98_remove, triggering the Oops. Add check to pty_unix98_remove to only clean up fsi if it is not NULL. Ooops: [ 23.020961] Oops: 0000 [#1] SMP [ 23.020976] Modules linked in: ppdev snd_hda_codec_generic snd_hda_intel snd_hda_codec parport_pc snd_hda_core snd_hwdep parport snd_pcm input_leds joydev snd_timer serio_raw snd soundcore i2c_piix4 mac_hid ib_iser rdma_cm iw_cm ib_cm ib_core configfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi autofs4 btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel qxl aes_x86_64 ttm lrw gf128mul glue_helper ablk_helper drm_kms_helper cryptd syscopyarea sysfillrect psmouse sysimgblt floppy fb_sys_fops drm pata_acpi jitterentropy_rng drbg ansi_cprng [ 23.020978] CPU: 0 PID: 1452 Comm: stress-ng-pty Not tainted 4.7.0-rc4+ #2 [ 23.020978] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 [ 23.020979] task: ffff88007ba30000 ti: ffff880078ea8000 task.ti: ffff880078ea8000 [ 23.020981] RIP: 0010:[<ffffffff813f11ff>] [<ffffffff813f11ff>] ida_remove+0x1f/0x120 [ 23.020981] RSP: 0018:ffff880078eabb60 EFLAGS: 00010a03 [ 23.020982] RAX: 4444444444444567 RBX: 0000000000000000 RCX: 000000000000001f [ 23.020982] RDX: 000000000000014c RSI: 000000000000026f RDI: 0000000000000000 [ 23.020982] RBP: ffff880078eabb70 R08: 0000000000000004 R09: 0000000000000036 [ 23.020983] R10: 000000000000026f R11: 0000000000000000 R12: 000000000000026f [ 23.020983] R13: 000000000000026f R14: ffff88007c944b40 R15: 000000000000026f [ 23.020984] FS: 00007f9a2f3cc700(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 23.020984] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 23.020985] CR2: 0000000000000010 CR3: 000000006c81b000 CR4: 00000000001406f0 [ 23.020988] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 23.020988] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 23.020988] Stack: [ 23.020989] 0000000000000000 000000000000026f ffff880078eabb90 ffffffff812a5a99 [ 23.020990] 0000000000000000 00000000fffffff4 ffff880078eabba8 ffffffff814f9cbe [ 23.020991] ffff88007965c800 ffff880078eabbc8 ffffffff814eef43 fffffffffffffff4 [ 23.020991] Call Trace: [ 23.021000] [<ffffffff812a5a99>] devpts_kill_index+0x29/0x50 [ 23.021002] [<ffffffff814f9cbe>] pty_unix98_remove+0x2e/0x50 [ 23.021006] [<ffffffff814eef43>] release_tty+0xb3/0x1b0 [ 23.021007] [<ffffffff814f18d4>] tty_init_dev+0xd4/0x1c0 [ 23.021011] [<ffffffff814f9fae>] ptmx_open+0xae/0x190 [ 23.021013] [<ffffffff812254ef>] chrdev_open+0xbf/0x1b0 [ 23.021015] [<ffffffff8121d973>] do_dentry_open+0x203/0x310 [ 23.021016] [<ffffffff81225430>] ? cdev_put+0x30/0x30 [ 23.021017] [<ffffffff8121ee44>] vfs_open+0x54/0x80 [ 23.021018] [<ffffffff8122b8fc>] ? may_open+0x8c/0x100 [ 23.021019] [<ffffffff8122f26b>] path_openat+0x2eb/0x1440 [ 23.021020] [<ffffffff81230534>] ? putname+0x54/0x60 [ 23.021022] [<ffffffff814f6f97>] ? n_tty_ioctl_helper+0x27/0x100 [ 23.021023] [<ffffffff81231651>] do_filp_open+0x91/0x100 [ 23.021024] [<ffffffff81230596>] ? getname_flags+0x56/0x1f0 [ 23.021026] [<ffffffff8123fc66>] ? __alloc_fd+0x46/0x190 [ 23.021027] [<ffffffff8121f1e4>] do_sys_open+0x124/0x210 [ 23.021028] [<ffffffff8121f2ee>] SyS_open+0x1e/0x20 [ 23.021035] [<ffffffff81845576>] entry_SYSCALL_64_fastpath+0x1e/0xa8 [ 23.021044] Code: 63 28 45 31 e4 eb dd 0f 1f 44 00 00 55 4c 63 d6 48 ba 89 88 88 88 88 88 88 88 4c 89 d0 b9 1f 00 00 00 48 f7 e2 48 89 e5 41 54 53 <8b> 47 10 48 89 fb 8d 3c c5 00 00 00 00 48 c1 ea 09 b8 01 00 00 [ 23.021045] RIP [<ffffffff813f11ff>] ida_remove+0x1f/0x120 [ 23.021045] RSP <ffff880078eabb60> [ 23.021046] CR2: 0000000000000010 Signed-off-by: Colin Ian King <colin.king@canonical.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-20 22:40:27 +08:00
if (fsi) {
devpts_kill_index(fsi, tty->index);
devpts_release(fsi);
}
TTY: pty, fix compilation warning When CONFIG_UNIX98_PTYS is unset, we see this warning in pty: drivers/tty/pty.c:409:13: warning: ‘pty_unix98_shutdown’ defined but not used Fix that by moving the function to a section which depends on that config. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Toralf Foerster <toralf.foerster@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-15 13:52:05 +08:00
}
pty: show associative slave of ptmx in fdinfo This patch adds "tty-index" field to /proc/PID/fdinfo/N if N specifies /dev/ptmx. The field shows the index of associative slave pts. Though a minor number is given for each pts instance, ptmx is not. It means there is no way in user-space to know the association between file descriptors for pts/n and ptmx. (n = 0, 1, ...) This is different from pipe. About pipe such association can be solved by inode of pipefs. Providing the way to know the association between pts/n and ptmx helps users understand the status of running system. lsof can utilize this field. Signed-off-by: Masatake YAMATO <yamato@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-18 05:27:59 +08:00
static void pty_show_fdinfo(struct tty_struct *tty, struct seq_file *m)
{
seq_printf(m, "tty-index:\t%d\n", tty->index);
}
tty: shutdown method Right now there are various drivers that try to use tty->count to know when they get the final close. Aristeau Rozanski showed while debugging the vt sysfs race that this isn't entirely safe. Instead of driver side tricks to work around this introduce a shutdown which is called when the tty is being destructed. This also means that the shutdown method is tied into the refcounting. Use this to rework the console close/sysfs logic. Remove lots of special case code from the tty core code. The pty code can now have a shutdown() method that replaces the special case hackery in the tree free up paths. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:30 +08:00
static const struct tty_operations ptm_unix98_ops = {
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
.lookup = ptm_unix98_lookup,
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
.install = pty_unix98_install,
PTY: remove one empty ops->remove Currently, there are two as a left-over from previous patches. Although we really need to provide an empty handler, we do not need two. So remove one of them. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:28 +08:00
.remove = pty_unix98_remove,
pty: prepare for tty->ops changes We are about to change the tty layer to avoid keeping private copies of all the methods in each tty. We have to update the pty layer first as it currently patches the ioctl method according to the tty type. Use multiple tty operations sets instead. Signed-off-by: Alan Cox <alan@redhat.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 15:54:10 +08:00
.open = pty_open,
.close = pty_close,
.write = pty_write,
.write_room = pty_write_room,
.flush_buffer = pty_flush_buffer,
.chars_in_buffer = pty_chars_in_buffer,
.unthrottle = pty_unthrottle,
tty: shutdown method Right now there are various drivers that try to use tty->count to know when they get the final close. Aristeau Rozanski showed while debugging the vt sysfs race that this isn't entirely safe. Instead of driver side tricks to work around this introduce a shutdown which is called when the tty is being destructed. This also means that the shutdown method is tied into the refcounting. Use this to rework the console close/sysfs logic. Remove lots of special case code from the tty core code. The pty code can now have a shutdown() method that replaces the special case hackery in the tree free up paths. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:30 +08:00
.ioctl = pty_unix98_ioctl,
tty: add compat_ioctl callbacks In order to avoid future diversions between fs/compat_ioctl.c and drivers/tty/pty.c, define .compat_ioctl callbacks for the relevant tty_operations structs. Since both pty_unix98_ioctl() and pty_bsd_ioctl() are compatible between 32-bit and 64-bit userspace no special translation is required. Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 22:15:14 +08:00
.compat_ioctl = pty_unix98_compat_ioctl,
tty: Move the handling of the tty release logic Now that we don't have tty->termios tied to drivers->tty we can untangle the logic here. In addition we can push the removal logic out of the destructor path. At that point we can think about sorting out tty_port and console and all the other ugly hangovers. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-18 00:06:57 +08:00
.resize = pty_resize,
pty: show associative slave of ptmx in fdinfo This patch adds "tty-index" field to /proc/PID/fdinfo/N if N specifies /dev/ptmx. The field shows the index of associative slave pts. Though a minor number is given for each pts instance, ptmx is not. It means there is no way in user-space to know the association between file descriptors for pts/n and ptmx. (n = 0, 1, ...) This is different from pipe. About pipe such association can be solved by inode of pipefs. Providing the way to know the association between pts/n and ptmx helps users understand the status of running system. lsof can utilize this field. Signed-off-by: Masatake YAMATO <yamato@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-18 05:27:59 +08:00
.cleanup = pty_cleanup,
.show_fdinfo = pty_show_fdinfo,
pty: prepare for tty->ops changes We are about to change the tty layer to avoid keeping private copies of all the methods in each tty. We have to update the pty layer first as it currently patches the ioctl method according to the tty type. Use multiple tty operations sets instead. Signed-off-by: Alan Cox <alan@redhat.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 15:54:10 +08:00
};
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
static const struct tty_operations pty_unix98_ops = {
.lookup = pts_unix98_lookup,
tty: extract the pty init time special cases The majority of the remaining init_dev code is pty special cases. We refactor this code into the driver->install method. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:39 +08:00
.install = pty_unix98_install,
PTY: remove one empty ops->remove Currently, there are two as a left-over from previous patches. Although we really need to provide an empty handler, we do not need two. So remove one of them. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:28 +08:00
.remove = pty_unix98_remove,
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
.open = pty_open,
.close = pty_close,
.write = pty_write,
.write_room = pty_write_room,
.flush_buffer = pty_flush_buffer,
.chars_in_buffer = pty_chars_in_buffer,
.unthrottle = pty_unthrottle,
.set_termios = pty_set_termios,
tty: Move packet mode flow control notifications to pty driver When a master pty is set to packet mode, flow control changes to the slave pty cause notifications to the master pty via reads and polls. However, these tests are occurring for all ttys, not just ptys. Implement flow control packet mode notifications in the pty driver. Only the slave side implements the flow control handlers since packet mode is asymmetric; the master pty receives notifications for slave-side changes, but not vice versa. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-11 03:06:32 +08:00
.start = pty_start,
.stop = pty_stop,
PTY: add tty_port This has *no* function in the PTY driver yet. However as the tty buffers will move to the tty_port structure, we will need tty_port for all TTYs in the system, PTY inclusive. For PTYs this is ensured by allocating 2 tty_port's in pty_install, i.e. where the tty->link is allocated. Both tty_port's are properly assigned to each end of the tty. Freeing is done at the same place where tty is freed, i.e. in tty->ops->cleanup. This means BTW that tty_port does not outlive TTY in PTY. This might be a subject to change in the future if we see some problems. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 19:35:30 +08:00
.cleanup = pty_cleanup,
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
};
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
/**
* ptmx_open - open a unix 98 pty master
* @inode: inode of device file
* @filp: file pointer to tty
*
* Allocate a unix98 pty master device from the ptmx driver.
*
* Locking: tty_mutex protects the init_dev work. tty->count should
tty: cleanup checkpatch warning in pty.c spaces are used for indent in 3 places of tty/pty.c, we change it to tab. Signed-off-by: Cong Ding <dinggnu@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-12 12:01:22 +08:00
* protect the rest.
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
* allocated_ptys_lock handles the list of free pty numbers
*/
tty: never hold BTM while getting tty_mutex tty_mutex is never taken with the BTM held, except for two corner cases that are worked around here. We give up the BTM before calling tty_release() in the error path of tty_open(). Similarly, we reorder the locking in ptmx_open() to get tty_mutex before the BTM. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-02 04:53:02 +08:00
static int ptmx_open(struct inode *inode, struct file *filp)
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
{
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
struct pts_fs_info *fsi;
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
struct tty_struct *tty;
devpts: more pty driver interface cleanups This is more prep-work for the upcoming pty changes. Still just code cleanup with no actual semantic changes. This removes a bunch pointless complexity by just having the slave pty side remember the dentry associated with the devpts slave rather than the inode. That allows us to remove all the "look up the dentry" code for when we want to remove it again. Together with moving the tty pointer from "inode->i_private" to "dentry->d_fsdata" and getting rid of pointless inode locking, this removes about 30 lines of code. Not only is the end result smaller, it's simpler and easier to understand. The old code, for example, depended on the d_find_alias() to not just find the dentry, but also to check that it is still hashed, which in turn validated the tty pointer in the inode. That is a _very_ roundabout way to say "invalidate the cached tty pointer when the dentry is removed". The new code just does dentry->d_fsdata = NULL; in devpts_pty_kill() instead, invalidating the tty pointer rather more directly and obviously. Don't do something complex and subtle when the obvious straightforward approach will do. The rest of the patch (ie apart from code deletion and the above tty pointer clearing) is just switching the calling convention to pass the dentry or file pointer around instead of the inode. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-26 11:04:08 +08:00
struct dentry *dentry;
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
int retval;
int index;
nonseekable_open(inode, filp);
tty: fix up atime/mtime mess, take three We first tried to avoid updating atime/mtime entirely (commit b0de59b5733d: "TTY: do not update atime/mtime on read/write"), and then limited it to only update it occasionally (commit 37b7f3c76595: "TTY: fix atime/mtime regression"), but it turns out that this was both insufficient and overkill. It was insufficient because we let people attach to the shared ptmx node to see activity without even reading atime/mtime, and it was overkill because the "only once a minute" means that you can't really tell an idle person from an active one with 'w'. So this tries to fix the problem properly. It marks the shared ptmx node as un-notifiable, and it lowers the "only once a minute" to a few seconds instead - still long enough that you can't time individual keystrokes, but short enough that you can tell whether somebody is active or not. Reported-by: Simon Kirby <sim@hostway.ca> Acked-by: Jiri Slaby <jslaby@suse.cz> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-01 22:32:21 +08:00
/* We refuse fsnotify events on ptmx, since it's a shared resource */
filp->f_mode |= FMODE_NONOTIFY;
TTY: make tty_add_file non-failing If tty_add_file fails at the point it is now, we have to revert all the changes we did to the tty. It means either decrease all refcounts if this was a tty reopen or delete the tty if it was newly allocated. There was a try to fix this in v3.0-rc2 using tty_release in 0259894c7 (TTY: fix fail path in tty_open). But instead it introduced a NULL dereference. It's because tty_release dereferences filp->private_data, but that one is set even in our tty_add_file. And when tty_add_file fails, it's still NULL/garbage. Hence tty_release cannot be called there. To circumvent the original leak (and the current NULL deref) we split tty_add_file into two functions, making the latter non-failing. In that case we may do the former early in open, where handling failures is easy. The latter stays as it is now. So there is no change in functionality. The original bug (leak) was introduced by f573bd176 (tty: Remove __GFP_NOFAIL from tty_add_file()). Thanks Dan for reporting this. Later, we may split tty_release into more functions and call only some of them in this fail path instead. (If at all possible.) Introduced-in: v2.6.37-rc2 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable <stable@vger.kernel.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-12 17:32:43 +08:00
retval = tty_alloc_file(filp);
if (retval)
return retval;
Revert "pty: fix the cached path of the pty slave file descriptor in the master" This reverts commit c8c03f1858331e85d397bacccd34ef409aae993c. It turns out that while fixing the ptmx file descriptor to have the correct 'struct path' to the associated slave pty is a really good thing, it breaks some user space tools for a very annoying reason. The problem is that /dev/ptmx and its associated slave pty (/dev/pts/X) are on different mounts. That was what caused us to have the wrong path in the first place (we would mix up the vfsmount of the 'ptmx' node, with the dentry of the pty slave node), but it also means that now while we use the right vfsmount, having the pty master open also keeps the pts mount busy. And it turn sout that that makes 'pbuilder' very unhappy, as noted by Stefan Lippers-Hollmann: "This patch introduces a regression for me when using pbuilder 0.228.7[2] (a helper to build Debian packages in a chroot and to create and update its chroots) when trying to umount /dev/ptmx (inside the chroot) on Debian/ unstable (full log and pbuilder configuration file[3] attached). [...] Setting up build-essential (12.3) ... Processing triggers for libc-bin (2.24-15) ... I: unmounting dev/ptmx filesystem W: Could not unmount dev/ptmx: umount: /var/cache/pbuilder/build/1340/dev/ptmx: target is busy (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1).)" apparently pbuilder tries to unmount the /dev/pts filesystem while still holding at least one master node open, which is arguably not very nice, but we don't break user space even when fixing other bugs. So this commit has to be reverted. I'll try to figure out a way to avoid caching the path to the slave pty in the master pty. The only thing that actually wants that slave pty path is the "TIOCGPTPEER" ioctl, and I think we could just recreate the path at that time. Reported-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: Eric W Biederman <ebiederm@xmission.com> Cc: Christian Brauner <christian.brauner@canonical.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-24 09:16:11 +08:00
fsi = devpts_acquire(filp);
devpts: Make each mount of devpts an independent filesystem. The /dev/ptmx device node is changed to lookup the directory entry "pts" in the same directory as the /dev/ptmx device node was opened in. If there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx uses that filesystem. Otherwise the open of /dev/ptmx fails. The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that userspace can now safely depend on each mount of devpts creating a new instance of the filesystem. Each mount of devpts is now a separate and equal filesystem. Reserved ttys are now available to all instances of devpts where the mounter is in the initial mount namespace. A new vfs helper path_pts is introduced that finds a directory entry named "pts" in the directory of the passed in path, and changes the passed in path to point to it. The helper path_pts uses a function path_parent_directory that was factored out of follow_dotdot. In the implementation of devpts: - devpts_mnt is killed as it is no longer meaningful if all mounts of devpts are equal. - pts_sb_from_inode is replaced by just inode->i_sb as all cached inodes in the tty layer are now from the devpts filesystem. - devpts_add_ref is rolled into the new function devpts_ptmx. And the unnecessary inode hold is removed. - devpts_del_ref is renamed devpts_release and reduced to just a deacrivate_super. - The newinstance mount option continues to be accepted but is now ignored. In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as they are never used. Documentation/filesystems/devices.txt is updated to describe the current situation. This has been verified to work properly on openwrt-15.05, centos5, centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3, ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1, slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01. With the caveat that on centos6 and on slackware-14.1 that there wind up being two instances of the devpts filesystem mounted on /dev/pts, the lower copy does not end up getting used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg KH <greg@kroah.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-02 23:29:47 +08:00
if (IS_ERR(fsi)) {
retval = PTR_ERR(fsi);
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
goto out_free_file;
devpts: Make each mount of devpts an independent filesystem. The /dev/ptmx device node is changed to lookup the directory entry "pts" in the same directory as the /dev/ptmx device node was opened in. If there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx uses that filesystem. Otherwise the open of /dev/ptmx fails. The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that userspace can now safely depend on each mount of devpts creating a new instance of the filesystem. Each mount of devpts is now a separate and equal filesystem. Reserved ttys are now available to all instances of devpts where the mounter is in the initial mount namespace. A new vfs helper path_pts is introduced that finds a directory entry named "pts" in the directory of the passed in path, and changes the passed in path to point to it. The helper path_pts uses a function path_parent_directory that was factored out of follow_dotdot. In the implementation of devpts: - devpts_mnt is killed as it is no longer meaningful if all mounts of devpts are equal. - pts_sb_from_inode is replaced by just inode->i_sb as all cached inodes in the tty layer are now from the devpts filesystem. - devpts_add_ref is rolled into the new function devpts_ptmx. And the unnecessary inode hold is removed. - devpts_del_ref is renamed devpts_release and reduced to just a deacrivate_super. - The newinstance mount option continues to be accepted but is now ignored. In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as they are never used. Documentation/filesystems/devices.txt is updated to describe the current situation. This has been verified to work properly on openwrt-15.05, centos5, centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3, ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1, slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01. With the caveat that on centos6 and on slackware-14.1 that there wind up being two instances of the devpts filesystem mounted on /dev/pts, the lower copy does not end up getting used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg KH <greg@kroah.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-02 23:29:47 +08:00
}
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
/* find a device that is not in use. */
tty: localise the lock The termios and other changes mean the other protections needed on the driver tty arrays should be adequate. Turn it all back on. This contains pieces folded in from the fixes made to the original patches | From: Geert Uytterhoeven <geert@linux-m68k.org> (fix m68k) | From: Paul Gortmaker <paul.gortmaker@windriver.com> (fix cris) | From: Jiri Kosina <jkosina@suze.cz> (lockdep) | From: Eric Dumazet <eric.dumazet@gmail.com> (lockdep) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 23:30:13 +08:00
mutex_lock(&devpts_mutex);
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
index = devpts_new_index(fsi);
tty: localise the lock The termios and other changes mean the other protections needed on the driver tty arrays should be adequate. Turn it all back on. This contains pieces folded in from the fixes made to the original patches | From: Geert Uytterhoeven <geert@linux-m68k.org> (fix m68k) | From: Paul Gortmaker <paul.gortmaker@windriver.com> (fix cris) | From: Jiri Kosina <jkosina@suze.cz> (lockdep) | From: Eric Dumazet <eric.dumazet@gmail.com> (lockdep) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 23:30:13 +08:00
mutex_unlock(&devpts_mutex);
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
retval = index;
if (index < 0)
devpts: Make each mount of devpts an independent filesystem. The /dev/ptmx device node is changed to lookup the directory entry "pts" in the same directory as the /dev/ptmx device node was opened in. If there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx uses that filesystem. Otherwise the open of /dev/ptmx fails. The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that userspace can now safely depend on each mount of devpts creating a new instance of the filesystem. Each mount of devpts is now a separate and equal filesystem. Reserved ttys are now available to all instances of devpts where the mounter is in the initial mount namespace. A new vfs helper path_pts is introduced that finds a directory entry named "pts" in the directory of the passed in path, and changes the passed in path to point to it. The helper path_pts uses a function path_parent_directory that was factored out of follow_dotdot. In the implementation of devpts: - devpts_mnt is killed as it is no longer meaningful if all mounts of devpts are equal. - pts_sb_from_inode is replaced by just inode->i_sb as all cached inodes in the tty layer are now from the devpts filesystem. - devpts_add_ref is rolled into the new function devpts_ptmx. And the unnecessary inode hold is removed. - devpts_del_ref is renamed devpts_release and reduced to just a deacrivate_super. - The newinstance mount option continues to be accepted but is now ignored. In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as they are never used. Documentation/filesystems/devices.txt is updated to describe the current situation. This has been verified to work properly on openwrt-15.05, centos5, centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3, ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1, slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01. With the caveat that on centos6 and on slackware-14.1 that there wind up being two instances of the devpts filesystem mounted on /dev/pts, the lower copy does not end up getting used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg KH <greg@kroah.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-02 23:29:47 +08:00
goto out_put_fsi;
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
mutex_lock(&tty_mutex);
tty = tty_init_dev(ptm_driver, index);
tty: localise the lock The termios and other changes mean the other protections needed on the driver tty arrays should be adequate. Turn it all back on. This contains pieces folded in from the fixes made to the original patches | From: Geert Uytterhoeven <geert@linux-m68k.org> (fix m68k) | From: Paul Gortmaker <paul.gortmaker@windriver.com> (fix cris) | From: Jiri Kosina <jkosina@suze.cz> (lockdep) | From: Eric Dumazet <eric.dumazet@gmail.com> (lockdep) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 23:30:13 +08:00
/* The tty returned here is locked so we can safely
drop the mutex */
mutex_unlock(&tty_mutex);
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
retval = PTR_ERR(tty);
if (IS_ERR(tty))
goto out;
fs: cleanup files_lock locking fs: cleanup files_lock locking Lock tty_files with a new spinlock, tty_files_lock; provide helpers to manipulate the per-sb files list; unexport the files_lock spinlock. Cc: linux-kernel@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-18 02:37:35 +08:00
pty: fix possible use after free of tty->driver_data This change fixes a bug for a corner case where we have the the last release from a pty master/slave coming from a previously opened /dev/tty file. When this happens, the tty->driver_data can be stale, due to all ptmx or pts/N files having already been closed before (and thus the inode related to these files, which tty->driver_data points to, being already freed/destroyed). The fix here is to keep a reference on the opened master ptmx inode. We maintain the inode referenced until the final pty_unix98_shutdown, and only pass this inode to devpts_kill_index. Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: <stable@vger.kernel.org> # 2.6.29+ Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-11 22:07:43 +08:00
/*
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
* From here on out, the tty is "live", and the index and
* fsi will be killed/put by the tty_release()
pty: fix possible use after free of tty->driver_data This change fixes a bug for a corner case where we have the the last release from a pty master/slave coming from a previously opened /dev/tty file. When this happens, the tty->driver_data can be stale, due to all ptmx or pts/N files having already been closed before (and thus the inode related to these files, which tty->driver_data points to, being already freed/destroyed). The fix here is to keep a reference on the opened master ptmx inode. We maintain the inode referenced until the final pty_unix98_shutdown, and only pass this inode to devpts_kill_index. Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: <stable@vger.kernel.org> # 2.6.29+ Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-11 22:07:43 +08:00
*/
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
tty->driver_data = fsi;
pty: fix possible use after free of tty->driver_data This change fixes a bug for a corner case where we have the the last release from a pty master/slave coming from a previously opened /dev/tty file. When this happens, the tty->driver_data can be stale, due to all ptmx or pts/N files having already been closed before (and thus the inode related to these files, which tty->driver_data points to, being already freed/destroyed). The fix here is to keep a reference on the opened master ptmx inode. We maintain the inode referenced until the final pty_unix98_shutdown, and only pass this inode to devpts_kill_index. Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: <stable@vger.kernel.org> # 2.6.29+ Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-11 22:07:43 +08:00
TTY: make tty_add_file non-failing If tty_add_file fails at the point it is now, we have to revert all the changes we did to the tty. It means either decrease all refcounts if this was a tty reopen or delete the tty if it was newly allocated. There was a try to fix this in v3.0-rc2 using tty_release in 0259894c7 (TTY: fix fail path in tty_open). But instead it introduced a NULL dereference. It's because tty_release dereferences filp->private_data, but that one is set even in our tty_add_file. And when tty_add_file fails, it's still NULL/garbage. Hence tty_release cannot be called there. To circumvent the original leak (and the current NULL deref) we split tty_add_file into two functions, making the latter non-failing. In that case we may do the former early in open, where handling failures is easy. The latter stays as it is now. So there is no change in functionality. The original bug (leak) was introduced by f573bd176 (tty: Remove __GFP_NOFAIL from tty_add_file()). Thanks Dan for reporting this. Later, we may split tty_release into more functions and call only some of them in this fail path instead. (If at all possible.) Introduced-in: v2.6.37-rc2 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable <stable@vger.kernel.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-12 17:32:43 +08:00
tty_add_file(tty, filp);
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
devpts: more pty driver interface cleanups This is more prep-work for the upcoming pty changes. Still just code cleanup with no actual semantic changes. This removes a bunch pointless complexity by just having the slave pty side remember the dentry associated with the devpts slave rather than the inode. That allows us to remove all the "look up the dentry" code for when we want to remove it again. Together with moving the tty pointer from "inode->i_private" to "dentry->d_fsdata" and getting rid of pointless inode locking, this removes about 30 lines of code. Not only is the end result smaller, it's simpler and easier to understand. The old code, for example, depended on the d_find_alias() to not just find the dentry, but also to check that it is still hashed, which in turn validated the tty pointer in the inode. That is a _very_ roundabout way to say "invalidate the cached tty pointer when the dentry is removed". The new code just does dentry->d_fsdata = NULL; in devpts_pty_kill() instead, invalidating the tty pointer rather more directly and obviously. Don't do something complex and subtle when the obvious straightforward approach will do. The rest of the patch (ie apart from code deletion and the above tty pointer clearing) is just switching the calling convention to pass the dentry or file pointer around instead of the inode. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-26 11:04:08 +08:00
dentry = devpts_pty_new(fsi, index, tty->link);
if (IS_ERR(dentry)) {
retval = PTR_ERR(dentry);
TTY: pty, release tty in all ptmx_open fail paths Mistakenly, commit 64ba3dc3143d (tty: never hold BTM while getting tty_mutex) switched one fail path in ptmx_open to not free the newly allocated tty. Fix that by jumping to the appropriate place. And rename the labels so that it's clear what is going on there. Introduced-in: v2.6.36-rc2 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@vger.kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-12 17:32:44 +08:00
goto err_release;
TTY: devpts, return created inode from devpts_pty_new The goal is to stop setting and using tty->driver_data in devpts code. It should be used solely by the driver's code, pty in this case. For the cleanup of layering, we will need the inode created in devpts_pty_new to be stored into slave's driver_data. So we convert devpts_pty_new to return the inode or an ERR_PTR-encoded error in case of failure. The move of 'inode = new_inode(sb);' from declarators to the code is only cosmetical, but it makes the code easier to read. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-19 04:26:28 +08:00
}
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
tty->link->driver_data = dentry;
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
retval = ptm_driver->ops->open(tty, filp);
tty: never hold BTM while getting tty_mutex tty_mutex is never taken with the BTM held, except for two corner cases that are worked around here. We give up the BTM before calling tty_release() in the error path of tty_open(). Similarly, we reorder the locking in ptmx_open() to get tty_mutex before the BTM. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-02 04:53:02 +08:00
if (retval)
pty: Repair TIOCGPTPEER The implementation of TIOCGPTPEER has two issues. When /dev/ptmx (as opposed to /dev/pts/ptmx) is opened the wrong vfsmount is passed to dentry_open. Which results in the kernel displaying the wrong pathname for the peer. The second is simply by caching the vfsmount and dentry of the peer it leaves them open, in a way they were not previously Which because of the inreased reference counts can cause unnecessary behaviour differences resulting in regressions. To fix these move the ioctl into tty_io.c at a generic level allowing the ioctl to have access to the struct file on which the ioctl is being called. This allows the path of the slave to be derived when opening the slave through TIOCGPTPEER instead of requiring the path to the slave be cached. Thus removing the need for caching the path. A new function devpts_ptmx_path is factored out of devpts_acquire and used to implement a function devpts_mntget. The new function devpts_mntget takes a filp to perform the lookup on and fsi so that it can confirm that the superblock that is found by devpts_ptmx_path is the proper superblock. v2: Lots of fixes to make the code actually work v3: Suggestions by Linus - Removed the unnecessary initialization of filp in ptm_open_peer - Simplified devpts_ptmx_path as gotos are no longer required [ This is the fix for the issue that was reverted in commit 143c97cc6529, but this time without breaking 'pbuilder' due to increased reference counts - Linus ] Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl") Reported-by: Christian Brauner <christian.brauner@canonical.com> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-25 04:13:29 +08:00
goto err_release;
TTY: pty, release tty in all ptmx_open fail paths Mistakenly, commit 64ba3dc3143d (tty: never hold BTM while getting tty_mutex) switched one fail path in ptmx_open to not free the newly allocated tty. Fix that by jumping to the appropriate place. And rename the labels so that it's clear what is going on there. Introduced-in: v2.6.36-rc2 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@vger.kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-12 17:32:44 +08:00
tty: Remove __func__ from tty_debug() macro Now that tty_debug() macro uses pr_debug(), the function name can be printed when using dynamic debug; printing the function name within the format string is redundant. Remove the __func__ parameter and print specifier from the format string. Add context to messages for when the function name is not printed by dynamic debug, or when dynamic debug is not enabled. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-09 02:01:19 +08:00
tty_debug_hangup(tty, "opening (count=%d)\n", tty->count);
pty: Add debug message for ptmx open Opens of /dev/ptmx don't use tty_open() so debug messages are not printed for those opens; print a debug message with the open count (which must always be 1) if TTY_DEBUG_HANGUP is defined. NB: Each tty core source file undefs support for debug messages. The relevant source file must be patched/edited to enable these messages. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-13 10:49:13 +08:00
tty: localise the lock The termios and other changes mean the other protections needed on the driver tty arrays should be adequate. Turn it all back on. This contains pieces folded in from the fixes made to the original patches | From: Geert Uytterhoeven <geert@linux-m68k.org> (fix m68k) | From: Paul Gortmaker <paul.gortmaker@windriver.com> (fix cris) | From: Jiri Kosina <jkosina@suze.cz> (lockdep) | From: Eric Dumazet <eric.dumazet@gmail.com> (lockdep) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 23:30:13 +08:00
tty_unlock(tty);
TTY: pty, release tty in all ptmx_open fail paths Mistakenly, commit 64ba3dc3143d (tty: never hold BTM while getting tty_mutex) switched one fail path in ptmx_open to not free the newly allocated tty. Fix that by jumping to the appropriate place. And rename the labels so that it's clear what is going on there. Introduced-in: v2.6.36-rc2 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@vger.kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-12 17:32:44 +08:00
return 0;
err_release:
tty: localise the lock The termios and other changes mean the other protections needed on the driver tty arrays should be adequate. Turn it all back on. This contains pieces folded in from the fixes made to the original patches | From: Geert Uytterhoeven <geert@linux-m68k.org> (fix m68k) | From: Paul Gortmaker <paul.gortmaker@windriver.com> (fix cris) | From: Jiri Kosina <jkosina@suze.cz> (lockdep) | From: Eric Dumazet <eric.dumazet@gmail.com> (lockdep) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-08 23:30:13 +08:00
tty_unlock(tty);
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
// This will also put-ref the fsi
tty: push the BKL down into the handlers a bit Start trying to untangle the remaining BKL mess Updated to fix missing unlock_kernel noted by Dan Carpenter Signed-off-by: Alan "I must be out of my tree" Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-30 21:18:29 +08:00
tty_release(inode, filp);
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
return retval;
out:
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
devpts_kill_index(fsi, index);
devpts: Make each mount of devpts an independent filesystem. The /dev/ptmx device node is changed to lookup the directory entry "pts" in the same directory as the /dev/ptmx device node was opened in. If there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx uses that filesystem. Otherwise the open of /dev/ptmx fails. The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that userspace can now safely depend on each mount of devpts creating a new instance of the filesystem. Each mount of devpts is now a separate and equal filesystem. Reserved ttys are now available to all instances of devpts where the mounter is in the initial mount namespace. A new vfs helper path_pts is introduced that finds a directory entry named "pts" in the directory of the passed in path, and changes the passed in path to point to it. The helper path_pts uses a function path_parent_directory that was factored out of follow_dotdot. In the implementation of devpts: - devpts_mnt is killed as it is no longer meaningful if all mounts of devpts are equal. - pts_sb_from_inode is replaced by just inode->i_sb as all cached inodes in the tty layer are now from the devpts filesystem. - devpts_add_ref is rolled into the new function devpts_ptmx. And the unnecessary inode hold is removed. - devpts_del_ref is renamed devpts_release and reduced to just a deacrivate_super. - The newinstance mount option continues to be accepted but is now ignored. In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as they are never used. Documentation/filesystems/devices.txt is updated to describe the current situation. This has been verified to work properly on openwrt-15.05, centos5, centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3, ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1, slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01. With the caveat that on centos6 and on slackware-14.1 that there wind up being two instances of the devpts filesystem mounted on /dev/pts, the lower copy does not end up getting used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Greg KH <greg@kroah.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-02 23:29:47 +08:00
out_put_fsi:
devpts_release(fsi);
devpts: clean up interface to pty drivers This gets rid of the horrible notion of having that struct inode *ptmx_inode be the linchpin of the interface between the pty code and devpts. By de-emphasizing the ptmx inode, a lot of things actually get cleaner, and we will have a much saner way forward. In particular, this will allow us to associate with any particular devpts instance at open-time, and not be artificially tied to one particular ptmx inode. The patch itself is actually fairly straightforward, and apart from some locking and return path cleanups it's pretty mechanical: - the interfaces that devpts exposes all take "struct pts_fs_info *" instead of "struct inode *ptmx_inode" now. NOTE! The "struct pts_fs_info" thing is a completely opaque structure as far as the pty driver is concerned: it's still declared entirely internally to devpts. So the pty code can't actually access it in any way, just pass it as a "cookie" to the devpts code. - the "look up the pts fs info" is now a single clear operation, that also does the reference count increment on the pts superblock. So "devpts_add/del_ref()" is gone, and replaced by a "lookup and get ref" operation (devpts_get_ref(inode)), along with a "put ref" op (devpts_put_ref()). - the pty master "tty->driver_data" field now contains the pts_fs_info, not the ptmx inode. - because we don't care about the ptmx inode any more as some kind of base index, the ref counting can now drop the inode games - it just gets the ref on the superblock. - the pts_fs_info now has a back-pointer to the super_block. That's so that we can easily look up the information we actually need. Although quite often, the pts fs info was actually all we wanted, and not having to look it up based on some magical inode makes things more straightforward. In particular, now that "devpts_get_ref(inode)" operation should really be the *only* place we need to look up what devpts instance we're associated with, and we do it exactly once, at ptmx_open() time. The other side of this is that one ptmx node could now be associated with multiple different devpts instances - you could have a single /dev/ptmx node, and then have multiple mount namespaces with their own instances of devpts mounted on /dev/pts/. And that's all perfectly sane in a model where we just look up the pts instance at open time. This will eventually allow us to get rid of our odd single-vs-multiple pts instance model, but this patch in itself changes no semantics, only an internal binding model. Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Serge Hallyn <serge.hallyn@ubuntu.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Jann Horn <jann@thejh.net> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-17 06:16:07 +08:00
out_free_file:
TTY: make tty_add_file non-failing If tty_add_file fails at the point it is now, we have to revert all the changes we did to the tty. It means either decrease all refcounts if this was a tty reopen or delete the tty if it was newly allocated. There was a try to fix this in v3.0-rc2 using tty_release in 0259894c7 (TTY: fix fail path in tty_open). But instead it introduced a NULL dereference. It's because tty_release dereferences filp->private_data, but that one is set even in our tty_add_file. And when tty_add_file fails, it's still NULL/garbage. Hence tty_release cannot be called there. To circumvent the original leak (and the current NULL deref) we split tty_add_file into two functions, making the latter non-failing. In that case we may do the former early in open, where handling failures is easy. The latter stays as it is now. So there is no change in functionality. The original bug (leak) was introduced by f573bd176 (tty: Remove __GFP_NOFAIL from tty_add_file()). Thanks Dan for reporting this. Later, we may split tty_release into more functions and call only some of them in this fail path instead. (If at all possible.) Introduced-in: v2.6.37-rc2 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable <stable@vger.kernel.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-12 17:32:43 +08:00
tty_free_file(filp);
tty: never hold BTM while getting tty_mutex tty_mutex is never taken with the BTM held, except for two corner cases that are worked around here. We give up the BTM before calling tty_release() in the error path of tty_open(). Similarly, we reorder the locking in ptmx_open() to get tty_mutex before the BTM. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-06-02 04:53:02 +08:00
return retval;
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
}
pty: make ptmx file ops read-only after init The ptmx_fops structure is only changed during init, so mark it as such. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-09 06:35:59 +08:00
static struct file_operations ptmx_fops __ro_after_init;
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +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
static void __init unix98_pty_init(void)
{
TTY: pty, switch to tty_alloc_driver Switch to the new driver allocation interface, as this is one of the special call-sites. Here, we need TTY_DRIVER_DYNAMIC_ALLOC to not allocate tty_driver->ports, cdevs and potentially other structures because we reserve too many lines in pty. Instead, it provides the tty_port<->tty_struct link in tty->ops->install already. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-09 04:26:41 +08:00
ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
TTY_DRIVER_RESET_TERMIOS |
TTY_DRIVER_REAL_RAW |
TTY_DRIVER_DYNAMIC_DEV |
TTY_DRIVER_DEVPTS_MEM |
TTY_DRIVER_DYNAMIC_ALLOC);
TTY: tty_alloc_driver() returns error pointers We changed these from alloc_tty_driver() to tty_alloc_driver() so the error handling needs to modified to check for IS_ERR() instead of NULL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 21:16:56 +08:00
if (IS_ERR(ptm_driver))
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
panic("Couldn't allocate Unix98 ptm driver");
TTY: pty, switch to tty_alloc_driver Switch to the new driver allocation interface, as this is one of the special call-sites. Here, we need TTY_DRIVER_DYNAMIC_ALLOC to not allocate tty_driver->ports, cdevs and potentially other structures because we reserve too many lines in pty. Instead, it provides the tty_port<->tty_struct link in tty->ops->install already. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-09 04:26:41 +08:00
pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
TTY_DRIVER_RESET_TERMIOS |
TTY_DRIVER_REAL_RAW |
TTY_DRIVER_DYNAMIC_DEV |
TTY_DRIVER_DEVPTS_MEM |
TTY_DRIVER_DYNAMIC_ALLOC);
TTY: tty_alloc_driver() returns error pointers We changed these from alloc_tty_driver() to tty_alloc_driver() so the error handling needs to modified to check for IS_ERR() instead of NULL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 21:16:56 +08:00
if (IS_ERR(pts_driver))
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
panic("Couldn't allocate Unix98 pts driver");
ptm_driver->driver_name = "pty_master";
ptm_driver->name = "ptm";
ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
ptm_driver->minor_start = 0;
ptm_driver->type = TTY_DRIVER_TYPE_PTY;
ptm_driver->subtype = PTY_TYPE_MASTER;
ptm_driver->init_termios = tty_std_termios;
ptm_driver->init_termios.c_iflag = 0;
ptm_driver->init_termios.c_oflag = 0;
ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
ptm_driver->init_termios.c_lflag = 0;
[PATCH] tty: switch to ktermios This is the grungy swap all the occurrences in the right places patch that goes with the updates. At this point we have the same functionality as before (except that sgttyb() returns speeds not zero) and are ready to begin turning new stuff on providing nobody reports lots of bugs If you are a tty driver author converting an out of tree driver the only impact should be termios->ktermios name changes for the speed/property setting functions from your upper layers. If you are implementing your own TCGETS function before then your driver was broken already and its about to get a whole lot more painful for you so please fix it 8) Also fill in c_ispeed/ospeed on init for most devices, although the current code will do this for you anyway but I'd like eventually to lose that extra paranoia [akpm@osdl.org: bluetooth fix] [mp3@de.ibm.com: sclp fix] [mp3@de.ibm.com: warning fix for tty3270] [hugh@veritas.com: fix tty_ioctl powerpc build] [jdike@addtoit.com: uml: fix ->set_termios declaration] Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 18:38:45 +08:00
ptm_driver->init_termios.c_ispeed = 38400;
ptm_driver->init_termios.c_ospeed = 38400;
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
ptm_driver->other = pts_driver;
tty: shutdown method Right now there are various drivers that try to use tty->count to know when they get the final close. Aristeau Rozanski showed while debugging the vt sysfs race that this isn't entirely safe. Instead of driver side tricks to work around this introduce a shutdown which is called when the tty is being destructed. This also means that the shutdown method is tied into the refcounting. Use this to rework the console close/sysfs logic. Remove lots of special case code from the tty core code. The pty code can now have a shutdown() method that replaces the special case hackery in the tree free up paths. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:30 +08:00
tty_set_operations(ptm_driver, &ptm_unix98_ops);
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
pts_driver->driver_name = "pty_slave";
pts_driver->name = "pts";
pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
pts_driver->minor_start = 0;
pts_driver->type = TTY_DRIVER_TYPE_PTY;
pts_driver->subtype = PTY_TYPE_SLAVE;
pts_driver->init_termios = tty_std_termios;
pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
[PATCH] tty: switch to ktermios This is the grungy swap all the occurrences in the right places patch that goes with the updates. At this point we have the same functionality as before (except that sgttyb() returns speeds not zero) and are ready to begin turning new stuff on providing nobody reports lots of bugs If you are a tty driver author converting an out of tree driver the only impact should be termios->ktermios name changes for the speed/property setting functions from your upper layers. If you are implementing your own TCGETS function before then your driver was broken already and its about to get a whole lot more painful for you so please fix it 8) Also fill in c_ispeed/ospeed on init for most devices, although the current code will do this for you anyway but I'd like eventually to lose that extra paranoia [akpm@osdl.org: bluetooth fix] [mp3@de.ibm.com: sclp fix] [mp3@de.ibm.com: warning fix for tty3270] [hugh@veritas.com: fix tty_ioctl powerpc build] [jdike@addtoit.com: uml: fix ->set_termios declaration] Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 18:38:45 +08:00
pts_driver->init_termios.c_ispeed = 38400;
pts_driver->init_termios.c_ospeed = 38400;
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
pts_driver->other = ptm_driver;
tty: Clean up the tty_init_dev changes further Fix up the naming, style and extract some bits of code into the driver specific code Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:42:00 +08:00
tty_set_operations(pts_driver, &pty_unix98_ops);
pty: Coding style and polish We've done the heavy lifting now its time to mop up a bit Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:43:38 +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 (tty_register_driver(ptm_driver))
panic("Couldn't register Unix98 ptm driver");
if (tty_register_driver(pts_driver))
panic("Couldn't register Unix98 pts driver");
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
/* Now create the /dev/ptmx special device */
tty_default_fops(&ptmx_fops);
ptmx_fops.open = ptmx_open;
cdev_init(&ptmx_cdev, &ptmx_fops);
if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
tty: cleanup the panic message the "\n" in panic message is excess, so we remove it in tty/pty.c as what it is used in other places. Signed-off-by: Cong Ding <dinggnu@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-12 12:01:21 +08:00
panic("Couldn't register /dev/ptmx driver");
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +08:00
device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
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
}
tty: Remove more special casing and out of place code Carry on pushing code out of tty_io when it belongs to other drivers. I'm not 100% happy with some of this and it will be worth revisiting some of the exports later when the restructuring work is done. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 17:41:42 +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
#else
static inline void unix98_pty_init(void) { }
#endif
static int __init pty_init(void)
{
legacy_pty_init();
unix98_pty_init();
return 0;
}
drivers/tty: make pty.c slightly more explicitly non-modular The Kconfig currently controlling compilation of this code is: drivers/tty/Kconfig:config LEGACY_PTYS drivers/tty/Kconfig: bool "Legacy (BSD) PTY support" ...and: drivers/tty/Kconfig:config UNIX98_PTYS drivers/tty/Kconfig: bool "Unix98 PTY support" if EXPERT combined with this: obj-$(CONFIG_LEGACY_PTYS) += pty.o obj-$(CONFIG_UNIX98_PTYS) += pty.o ...meaning that it currently is not being built as a module by anyone. Lets remove the traces of modularity we can so that when reading the driver there is less doubt it is builtin-only. Since module_init translates to device_initcall in the non-modular case, the init ordering remains unchanged with this commit. We don't delete the module.h include since other parts of the file are using content from there. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-20 05:48:05 +08:00
device_initcall(pty_init);