Commit Graph

244 Commits

Author SHA1 Message Date
Linus Torvalds
853da00220 Merge branch 'audit.b38' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b38' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  [PATCH] Abnormal End of Processes
  [PATCH] match audit name data
  [PATCH] complete message queue auditing
  [PATCH] audit inode for all xattr syscalls
  [PATCH] initialize name osid
  [PATCH] audit signal recipients
  [PATCH] add SIGNAL syscall class (v3)
  [PATCH] auditing ptrace
2007-05-11 09:57:16 -07:00
Davide Libenzi
fba2afaaec signal/timer/event: signalfd core
This patch series implements the new signalfd() system call.

I took part of the original Linus code (and you know how badly it can be
broken :), and I added even more breakage ;) Signals are fetched from the same
signal queue used by the process, so signalfd will compete with standard
kernel delivery in dequeue_signal().  If you want to reliably fetch signals on
the signalfd file, you need to block them with sigprocmask(SIG_BLOCK).  This
seems to be working fine on my Dual Opteron machine.  I made a quick test
program for it:

http://www.xmailserver.org/signafd-test.c

The signalfd() system call implements signal delivery into a file descriptor
receiver.  The signalfd file descriptor if created with the following API:

int signalfd(int ufd, const sigset_t *mask, size_t masksize);

The "ufd" parameter allows to change an existing signalfd sigmask, w/out going
to close/create cycle (Linus idea).  Use "ufd" == -1 if you want a brand new
signalfd file.

The "mask" allows to specify the signal mask of signals that we are interested
in.  The "masksize" parameter is the size of "mask".

The signalfd fd supports the poll(2) and read(2) system calls.  The poll(2)
will return POLLIN when signals are available to be dequeued.  As a direct
consequence of supporting the Linux poll subsystem, the signalfd fd can use
used together with epoll(2) too.

The read(2) system call will return a "struct signalfd_siginfo" structure in
the userspace supplied buffer.  The return value is the number of bytes copied
in the supplied buffer, or -1 in case of error.  The read(2) call can also
return 0, in case the sighand structure to which the signalfd was attached,
has been orphaned.  The O_NONBLOCK flag is also supported, and read(2) will
return -EAGAIN in case no signal is available.

If the size of the buffer passed to read(2) is lower than sizeof(struct
signalfd_siginfo), -EINVAL is returned.  A read from the signalfd can also
return -ERESTARTSYS in case a signal hits the process.  The format of the
struct signalfd_siginfo is, and the valid fields depends of the (->code &
__SI_MASK) value, in the same way a struct siginfo would:

struct signalfd_siginfo {
	__u32 signo;	/* si_signo */
	__s32 err;	/* si_errno */
	__s32 code;	/* si_code */
	__u32 pid;	/* si_pid */
	__u32 uid;	/* si_uid */
	__s32 fd;	/* si_fd */
	__u32 tid;	/* si_fd */
	__u32 band;	/* si_band */
	__u32 overrun;	/* si_overrun */
	__u32 trapno;	/* si_trapno */
	__s32 status;	/* si_status */
	__s32 svint;	/* si_int */
	__u64 svptr;	/* si_ptr */
	__u64 utime;	/* si_utime */
	__u64 stime;	/* si_stime */
	__u64 addr;	/* si_addr */
};

[akpm@linux-foundation.org: fix signalfd_copyinfo() on i386]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 08:29:36 -07:00
Amy Griffis
e54dc2431d [PATCH] audit signal recipients
When auditing syscalls that send signals, log the pid and security
context for each target process. Optimize the data collection by
adding a counter for signal-related rules, and avoiding allocating an
aux struct unless we have more than one target process. For process
groups, collect pid/context data in blocks of 16. Move the
audit_signal_info() hook up in check_kill_permission() so we audit
attempts where permission is denied.

Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-05-11 05:38:25 -04:00
Oleg Nesterov
10ab825bde change kernel threads to ignore signals instead of blocking them
Currently kernel threads use sigprocmask(SIG_BLOCK) to protect against
signals.  This doesn't prevent the signal delivery, this only blocks
signal_wake_up().  Every "killall -33 kthreadd" means a "struct siginfo"
leak.

Change kthreadd_setup() to set all handlers to SIG_IGN instead of blocking
them (make a new helper ignore_signals() for that).  If the kernel thread
needs some signal, it should use allow_signal() anyway, and in that case it
should not use CLONE_SIGHAND.

Note that we can't change daemonize() (should die!) in the same way,
because it can be used along with CLONE_SIGHAND.  This means that
allow_signal() still should unblock the signal to work correctly with
daemonize()ed threads.

However, disallow_signal() doesn't block the signal any longer but ignores
it.

NOTE: with or without this patch the kernel threads are not protected from
handle_stop_signal(), this seems harmless, but not good.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:53 -07:00
Oleg Nesterov
a4798833d2 zap_other_threads: remove unneeded ->exit_signal change
We already depend on fact that all sub-threads have ->exit_signal == -1, no
need to set it in zap_other_threads().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:53 -07:00
Roland McGrath
55c0d1f83e Move sig_kernel_* et al macros to linux/signal.h
This patch moves the sig_kernel_* and related macros from kernel/signal.c
to linux/signal.h, and cleans them up slightly.  I need the sig_kernel_*
macros for default signal behavior in the utrace code, and want to avoid
duplication or overhead to share the knowledge.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:49 -07:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Christoph Lameter
0a31bd5f2b KMEM_CACHE(): simplify slab cache creation
This patch provides a new macro

KMEM_CACHE(<struct>, <flags>)

to simplify slab creation. KMEM_CACHE creates a slab with the name of the
struct, with the size of the struct and with the alignment of the struct.
Additional slab flags may be specified if necessary.

Example

struct test_slab {
	int a,b,c;
	struct list_head;
} __cacheline_aligned_in_smp;

test_slab_cache = KMEM_CACHE(test_slab, SLAB_PANIC)

will create a new slab named "test_slab" of the size sizeof(struct
test_slab) and aligned to the alignment of test slab.  If it fails then we
panic.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:12:55 -07:00
Linus Torvalds
b0138a6cb7 Merge master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6: (78 commits)
  [PARISC] Use symbolic last syscall in __NR_Linux_syscalls
  [PARISC] Add missing statfs64 and fstatfs64 syscalls
  Revert "[PARISC] Optimize TLB flush on SMP systems"
  [PARISC] Compat signal fixes for 64-bit parisc
  [PARISC] Reorder syscalls to match unistd.h
  Revert "[PATCH] make kernel/signal.c:kill_proc_info() static"
  [PARISC] fix sys_rt_sigqueueinfo
  [PARISC] fix section mismatch warnings in harmony sound driver
  [PARISC] do not export get_register/set_register
  [PARISC] add ENTRY()/ENDPROC() and simplify assembly of HP/UX emulation code
  [PARISC] convert to use CONFIG_64BIT instead of __LP64__
  [PARISC] use CONFIG_64BIT instead of __LP64__
  [PARISC] add ASM_EXCEPTIONTABLE_ENTRY() macro
  [PARISC] more ENTRY(), ENDPROC(), END() conversions
  [PARISC] fix ENTRY() and ENDPROC() for 64bit-parisc
  [PARISC] Fixes /proc/cpuinfo cache output on B160L
  [PARISC] implement standard ENTRY(), END() and ENDPROC()
  [PARISC] kill ENTRY_SYS_CPUS
  [PARISC] clean up debugging printks in smp.c
  [PARISC] factor syscall_restart code out of do_signal
  ...

Fix conflict in include/linux/sched.h due to kill_proc_info() being made
publicly available to PARISC again.
2007-02-26 12:48:06 -08:00
Matthew Wilcox
c3de4b3815 Revert "[PATCH] make kernel/signal.c:kill_proc_info() static"
This reverts commit d3228a887c.
DeBunk this code.  We need it for compat_sys_rt_sigqueueinfo.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2007-02-17 01:20:07 -05:00
Thomas Gleixner
8bfd9a7a22 [PATCH] hrtimers: prevent possible itimer DoS
Fix potential setitimer DoS with high-res timers by pushing itimer rearm
processing to process context.

[Fixes from: Ingo Molnar <mingo@elte.hu>]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:59 -08:00
Eric W. Biederman
27b0b2f44a [PATCH] pid: remove the now unused kill_pg kill_pg_info and __kill_pg_info
Now that I have changed all of the in-tree users remove the old version of
these functions.  This should make it clear to any out of tree users that they
should be using kill_pgrp kill_pgrp_info or __kill_pgrp_info instead.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:32 -08:00
Eric W. Biederman
3e7cd6c413 [PATCH] pid: replace is_orphaned_pgrp with is_current_pgrp_orphaned
Every call to is_orphaned_pgrp passed in process_group(current) which is racy
with respect to another thread changing our process group.  It didn't bite us
because we were dealing with integers and the worse we would get would be a
stale answer.

In switching the checks to use struct pid to be a little more efficient and
prepare the way for pid namespaces this race became apparent.

So I simplified the calls to the more specialized is_current_pgrp_orphaned so
I didn't have to worry about making logic changes to avoid the race.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:32 -08:00
Eric W. Biederman
8d42db189c [PATCH] signal: rewrite kill_something_info so it uses newer helpers
The goal is to remove users of the old signal helper functions so they can be
removed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:31 -08:00
Robert P. J. Day
72fd4a35a8 [PATCH] Numerous fixes to kernel-doc info in source files.
A variety of (mostly) innocuous fixes to the embedded kernel-doc content in
source files, including:

  * make multi-line initial descriptions single line
  * denote some function names, constants and structs as such
  * change erroneous opening '/*' to '/**' in a few places
  * reword some text for clarity

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:32 -08:00
Oleg Nesterov
0c12b51712 [PATCH] kill_pid_info: kill acquired_tasklist_lock
Kill acquired_tasklist_lock, sig_needs_tasklist() is very cheap nowadays.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:26 -08:00
Rafael J. Wysocki
3df494a32b [PATCH] PM: Fix freezing of stopped tasks
Currently, if a task is stopped (ie.  it's in the TASK_STOPPED state), it
is considered by the freezer as unfreezeable.  However, there may be a race
between the freezer and the delivery of the continuation signal to the task
resulting in the task running after we have finished freezing the other
tasks.  This, in turn, may lead to undesirable effects up to and including
data corruption.

To prevent this from happening we first need to make the freezer consider
stopped tasks as freezeable.  For this purpose we need to make freezeable()
stop returning 0 for these tasks and we need to force them to enter the
refrigerator.  However, if there's no continuation signal in the meantime,
the stopped tasks should remain stopped after all processes have been
thawed, so we need to send an additional SIGSTOP to each of them before
waking it up.

Also, a stopped task that has just been woken up should first check if
there's a freezing request for it and go to the refrigerator if that's the
case.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:49 -08:00
Sukadev Bhattiprolu
84d737866e [PATCH] add child reaper to pid_namespace
Add a per pid_namespace child-reaper.  This is needed so processes are reaped
within the same pid space and do not spill over to the parent pid space.  Its
also needed so containers preserve existing semantic that pid == 1 would reap
orphaned children.

This is based on Eric Biederman's patch: http://lkml.org/lkml/2006/2/6/285

Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:52 -08:00
Cedric Le Goater
937949d9ed [PATCH] add process_session() helper routine
Replace occurences of task->signal->session by a new process_session() helper
routine.

It will be useful for pid namespaces to abstract the session pid number.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:51 -08:00
Adrian Bunk
d3228a887c [PATCH] make kernel/signal.c:kill_proc_info() static
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:39 -08:00
Nigel Cunningham
7dfb71030f [PATCH] Add include/linux/freezer.h and move definitions from sched.h
Move process freezing functions from include/linux/sched.h to freezer.h, so
that modifications to the freezer or the kernel configuration don't require
recompiling just about everything.

[akpm@osdl.org: fix ueagle driver]
Signed-off-by: Nigel Cunningham <nigel@suspend2.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:27 -08:00
Christoph Lameter
e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Linus Torvalds
10b1fbdb0a Make sure "user->sigpending" count is in sync
The previous commit (45c18b0bb5, aka "Fix
unlikely (but possible) race condition on task->user access") fixed a
potential oops due to __sigqueue_alloc() getting its "user" pointer out
of sync with switch_user(), and accessing a user pointer that had been
de-allocated on another CPU.

It still left another (much less serious) problem, where a concurrent
__sigqueue_alloc and swich_user could cause sigqueue_alloc to do signal
pending reference counting for a _different_ user than the one it then
actually ended up using.  No oops, but we'd end up with the wrong signal
accounting.

Another case of Oleg's eagle-eyes picking up the problem.

This is trivially fixed by just making sure we load whichever "user"
structure we decide to use (it doesn't matter _which_ one we pick, we
just need to pick one) just once.

Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-04 13:03:00 -08:00
Eric W. Biederman
2425c08b37 [PATCH] usb: fixup usb so it uses struct pid
The problem with remembering a user space process by its pid is that it is
possible that the process will exit, pid wrap around will occur.
Converting to a struct pid avoid that problem, and paves the way for
implementing a pid namespace.

Also since usb is the only user of kill_proc_info_as_uid rename
kill_proc_info_as_uid to kill_pid_info_as_uid and have the new version take
a struct pid.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:15 -07:00
Eric W. Biederman
c4b92fc112 [PATCH] pid: implement signal functions that take a struct pid *
Currently the signal functions all either take a task or a pid_t argument.
This patch implements variants that take a struct pid *.  After all of the
users have been update it is my intention to remove the variants that take a
pid_t as using pid_t can be more work (an extra hash table lookup) and
difficult to get right in the presence of multiple pid namespaces.

There are two kinds of functions introduced in this patch.  The are the
general use functions kill_pgrp and kill_pid which take a priv argument that
is ultimately used to create the appropriate siginfo information, Then there
are _kill_pgrp_info, kill_pgrp_info, kill_pid_info the internal implementation
helpers that take an explicit siginfo.

The distinction is made because filling out an explcit siginfo is tricky, and
will be even more tricky when pid namespaces are introduced.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:13 -07:00
Roland McGrath
27d91e07f9 [PATCH] __dequeue_signal() cleanup
This tightens up __dequeue_signal a little.  It also avoids doing
recalc_sigpending twice in a row, instead doing it once in dequeue_signal.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:15 -07:00
David Howells
f269fdd182 [PATCH] NOMMU: move the fallback arch_vma_name() to a sensible place
Move the fallback arch_vma_name() to a sensible place (kernel/signal.c).

Currently it's in fs/proc/task_mmu.c, a file that is dependent on both
CONFIG_PROC_FS and CONFIG_MMU being enabled, but it's used from
kernel/signal.c from where it is called unconditionally.

[akpm@osdl.org: build fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:15 -07:00
Linus Torvalds
ae74c3b69a Fix force_sig_info() semantics after cleanups
Suresh points out that commit b0423a0d9c
broke the semantics of a synchronous signal like SIGSEGV occurring
recursively inside its own handler handler (or, indeed, any other
context when the signal was blocked).

That was unintentional, and this fixes things up by reinstating the old
semantics, but without reverting the cleanups.

Cc: Paul E. McKenney <paulmck@us.ibm.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-02 20:17:49 -07:00
Linus Torvalds
22a3e233ca Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  Remove obsolete #include <linux/config.h>
  remove obsolete swsusp_encrypt
  arch/arm26/Kconfig typos
  Documentation/IPMI typos
  Kconfig: Typos in net/sched/Kconfig
  v9fs: do not include linux/version.h
  Documentation/DocBook/mtdnand.tmpl: typo fixes
  typo fixes: specfic -> specific
  typo fixes in Documentation/networking/pktgen.txt
  typo fixes: occuring -> occurring
  typo fixes: infomation -> information
  typo fixes: disadvantadge -> disadvantage
  typo fixes: aquire -> acquire
  typo fixes: mecanism -> mechanism
  typo fixes: bandwith -> bandwidth
  fix a typo in the RTC_CLASS help text
  smb is no longer maintained

Manually merged trivial conflict in arch/um/kernel/vmlinux.lds.S
2006-06-30 15:39:30 -07:00
David Quigley
8f95dc58d0 [PATCH] SELinux: add security hook call to kill_proc_info_as_uid
This patch adds a call to the extended security_task_kill hook introduced by
the prior patch to the kill_proc_info_as_uid function so that these signals
can be properly mediated by security modules.  It also updates the existing
hook call in check_kill_permission.

Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:37 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Oleg Nesterov
d5f70c00ad [PATCH] coredump: kill ptrace related stuff
With this patch zap_process() sets SIGNAL_GROUP_EXIT while sending SIGKILL to
the thread group.  This means that a TASK_TRACED task

	1. Will be awakened by signal_wake_up(1)

	2. Can't sleep again via ptrace_notify()

	3. Can't go to do_signal_stop() after return
	   from ptrace_stop() in get_signal_to_deliver()

So we can remove all ptrace related stuff from coredump path.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:27 -07:00
Al Viro
e1396065e0 [PATCH] collect sid of those who send signals to auditd
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-06-20 05:25:21 -04:00
Roland McGrath
e57a505984 [PATCH] fix non-leader exec under ptrace
This reverts most of commit 30e0fca6c1.
It broke the case of non-leader MT exec when ptraced.
I think the bug it was intended to fix was already addressed by commit
788e05a67c.

Signed-off-by: Roland McGrath <roland@redhat.com>
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-14 08:59:13 -07:00
Oleg Nesterov
a145410dcc [PATCH] __group_complete_signal: remove bogus BUG_ON
Commit e56d090310

   [PATCH] RCU signal handling

made this BUG_ON() unsafe. This code runs under ->siglock,
while switch_exec_pids() takes tasklist_lock.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 07:34:01 -07:00
Eric Sesterhenn
fda8bd78a1 BUG_ON() Conversion in kernel/signal.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-02 13:44:47 +02:00
Pavel Machek
85b6bce365 [PATCH] Fix suspend with traced tasks
strace /bin/bash misbehaves after resume; this fixes it.

(akpm: it's scary calling refrigerator() in state TASK_TRACED, but it seems to
do the right thing).

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:50 -08:00
Oleg Nesterov
547679087b [PATCH] send_sigqueue: simplify and fix the race
send_sigqueue() checks PF_EXITING, then locks p->sighand->siglock.  This is
unsafe: 'p' can exit in between and set ->sighand = NULL.  The race is
theoretical, the window is tiny and irqs are disabled by the caller, so I
don't think we need the fix for -stable tree.

Convert send_sigqueue() to use lock_task_sighand() helper.

Also, delete 'p->flags & PF_EXITING' re-check, it is unneeded and the
comment is wrong.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
a1d5e21e3e [PATCH] do_notify_parent_cldstop: remove 'to_self' param
The previous patch has changed callsites of do_notify_parent_cldstop() so that
to_self == (->ptrace & PT_PTRACED) always (as it should be).  We can remove
this parameter now.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
883606a7c9 [PATCH] finish_stop: don't check stop_count < 0
Remove an obscure 'stop_count < 0' check in finish_stop().  The previous patch
made this case impossible.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
dac27f4a09 [PATCH] simplify do_signal_stop()
do_signal_stop() considers 'thread_group_empty()' as a special case.
This was needed to avoid taking tasklist_lock. Since this lock is
unneeded any longer, we can remove this special case and simplify
the code even more.

Also, before this patch, finish_stop() was called with stop_count == -1
for 'thread_group_empty()' case. This is not strictly wrong, but confusing
and unneeded.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
88531f725b [PATCH] do_sigaction: don't take tasklist_lock
do_sigaction() does not need tasklist_lock anymore, we can simplify the code.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:44 -08:00
Oleg Nesterov
a122b341b7 [PATCH] do_signal_stop: don't take tasklist_lock
do_signal_stop() does not need tasklist_lock anymore.  So it does not need to
do misc re-checks, and we can simplify the code.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
6108ccd3e2 [PATCH] relax sig_needs_tasklist()
handle_stop_signal() does not need tasklist_lock for SIG_KERNEL_STOP_MASK
signals anymore.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
6a14c5c9da [PATCH] move __exit_signal() to kernel/exit.c
__exit_signal() is private to release_task() now.  I think it is better to
make it static in kernel/exit.c and export flush_sigqueue() instead - this
function is much more simple and straightforward.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
c81addc9d3 [PATCH] rename __exit_sighand to cleanup_sighand
Cosmetic, rename __exit_sighand to cleanup_sighand and move it close to
copy_sighand().

This matches copy_signal/cleanup_signal naming, and I think it is easier to
follow.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
29ff471234 [PATCH] cleanup __exit_signal()
This patch factors out duplicated code under 'if' branches.  Also, BUG_ON()
conversions and whitespace cleanups.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:43 -08:00
Oleg Nesterov
6b3934ef52 [PATCH] copy_process: cleanup bad_fork_cleanup_signal
__exit_signal() does important cleanups atomically under ->siglock.  It is
also called from copy_process's error path.  This is not good, for example we
can't move __unhash_process() under ->siglock for that reason.

We should not mix these 2 paths, just look at ugly 'if (p->sighand)' under
'bad_fork_cleanup_sighand:' label.  For copy_process() case it is sufficient
to just backout copy_signal(), nothing more.

Again, nobody can see this task yet.  For CLONE_THREAD case we just decrement
signal->count, otherwise nobody can see this ->signal and we can free it
lockless.

This patch assumes it is safe to do exit_thread_group_keys() without
tasklist_lock.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
7001510d0c [PATCH] copy_process: cleanup bad_fork_cleanup_sighand
The only caller of exit_sighand(tsk) is copy_process's error path.  We can
call __exit_sighand() directly and kill exit_sighand().

This 'tsk' was not yet registered in pid_hash[] or init_task.tasks, it has no
external references, nobody can see it, and

	IF (clone_flags & CLONE_SIGHAND)
		At least 'current' has a reference to ->sighand, this
		means atomic_dec_and_test(sighand->count) can't be true.

	ELSE
		Nobody can see this ->sighand, this means we can free it
		without any locking.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
a9e88e84b5 [PATCH] introduce sig_needs_tasklist() helper
In my opinion this patch cleans up the code.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
f63ee72e0f [PATCH] introduce lock_task_sighand() helper
Add lock_task_sighand() helper and converts group_send_sig_info() to use
it.  Hopefully we will have more users soon.

This patch also removes '!sighand->count' and '!p->usage' checks, I think
they both are bogus, racy and unneeded (but probably it makes sense to
restore them as BUG_ON()s).

->sighand is cleared and it's ->count is decremented in release_task() with
sighand->siglock held, so it is a bug to have '!p->usage || !->count' after
we already locked and verified it is the same.  On the other hand, an
already dead task without ->sighand can have a non-zero ->usage due to
ptrace, for example.

If we read the stale value of ->sighand we must see the change after
spin_lock(), because that change was done while holding that same old
->sighand.siglock.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Oleg Nesterov
aa1757f90b [PATCH] convert sighand_cache to use SLAB_DESTROY_BY_RCU
This patch borrows a clever Hugh's 'struct anon_vma' trick.

Without tasklist_lock held we can't trust task->sighand until we locked it
and re-checked that it is still the same.

But this means we don't need to defer 'kmem_cache_free(sighand)'.  We can
return the memory to slab immediately, all we need is to be sure that
sighand->siglock can't dissapear inside rcu protected section.

To do so we need to initialize ->siglock inside ctor function,
SLAB_DESTROY_BY_RCU does the rest.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:42 -08:00
Eric W. Biederman
fef23e7fbb [PATCH] exec: allow init to exec from any thread.
After looking at the problem of init calling exec some more I figured out
an easy way to make the code work.

The actual symptom without out this patch is that all threads will die
except pid == 1, and the thread calling exec.  The thread calling exec will
wait forever for pid == 1 to die.

Since pid == 1 does not install a handler for SIGKILL it will never die.

This modifies the tests for init from current->pid == 1 to the equivalent
current == child_reaper.  And then it causes exec in the ugly case to
modify child_reaper.

The only weird symptom is that you wind up with an init process that
doesn't have the oldest start time on the box.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 18:36:40 -08:00
Oleg Nesterov
a26fd335b4 [PATCH] sigprocmask: kill unneeded temp var
Cleanup, remove unneeded double copying of current->blocked.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:15 -08:00
Rafael J. Wysocki
fc558a7496 [PATCH] swsusp: finally solve mysqld problem
This patch from Pavel moves userland freeze signals handling into more logical
place.  It now hits even with mysqld running.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:08 -08:00
Oleg Nesterov
9ac95f2f90 [PATCH] do_sigaction: cleanup ->sa_mask manipulation
Clear unblockable signals beforehand.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-09 16:17:36 -08:00
Oleg Nesterov
c70d3d703a [PATCH] sys_signal: initialize ->sa_mask
Pointed out by Linus Torvalds.

sys_signal() forgets to initialize ->sa_mask.

( I suspect arch/ia64/ia32/ia32_signal.c:sys32_signal()
  also needs this fix )

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-09 16:17:36 -08:00
Andrew Morton
514a01b880 [PATCH] uninline __sigqueue_free()
Five callsites.  I dunno how all this crap got back in there :(

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:10 -08:00
David Woodhouse
150256d8aa [PATCH] Generic sys_rt_sigsuspend()
The TIF_RESTORE_SIGMASK flag allows us to have a generic implementation of
sys_rt_sigsuspend() instead of duplicating it for each architecture.  This
provides such an implementation and makes arch/powerpc use it.

It also tidies up the ppc32 sys_sigsuspend() to use TIF_RESTORE_SIGMASK.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:29 -08:00
Arjan van de Ven
858119e159 [PATCH] Unlinline a bunch of other functions
Remove the "inline" keyword from a bunch of big functions in the kernel with
the goal of shrinking it by 30kb to 40kb

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:06 -08:00
Randy.Dunlap
c59ede7b78 [PATCH] move capable() to capability.h
- Move capable() from sched.h to capability.h;

- Use <linux/capability.h> where capable() is used
	(in include/, block/, ipc/, kernel/, a few drivers/,
	mm/, security/, & sound/;
	many more drivers/ to go)

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:13 -08:00
Oleg Nesterov
86174cdcb4 [PATCH] remove unneeded sig->curr_target recalculation
This patch removes unneeded sig->curr_target recalculation under 'if
(atomic_dec_and_test(&sig->count))' in __exit_signal().

When sig->count == 0 the signal can't be sent to this task and
next_thread(tsk) == tsk anyway.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:57 -08:00
Oleg Nesterov
0811af28ce [PATCH] kill_proc_info_as_uid: don't use hardcoded constants
Use symbolic names instead of hardcoded constants.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Harald Welte <laforge@gnumonks.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:55 -08:00
George Anzinger
71fabd5e48 [PATCH] sigaction should clear all signals on SIG_IGN, not just < 32
While rooting aroung in the signal code trying to understand how to fix the
SIG_IGN ploy (set sig handler to SIG_IGN and flood system with high speed
repeating timers) I came across what, I think, is a problem in sigaction()
in that when processing a SIG_IGN request it flushes signals from 1 to
SIGRTMIN and leaves the rest.  Attempt to fix this.

Signed-off-by: George Anzinger <george@mvista.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:53 -08:00
Paul E. McKenney
2d89c92907 [PATCH] Simpler signal-exit concurrency handling
Some simplification in checking signal delivery against concurrent exit.
Instead of using get_task_struct_rcu(), which increments the task_struct
reference count, check the reference count after acquiring sighand lock.

Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:40 -08:00
Ingo Molnar
e56d090310 [PATCH] RCU signal handling
RCU tasklist_lock and RCU signal handling: send signals RCU-read-locked
instead of tasklist_lock read-locked.  This is a scalability improvement on
SMP and a preemption-latency improvement under PREEMPT_RCU.

Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: William Irwin <wli@holomorphy.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:40 -08:00
Heiko Carstens
b17b0421d7 [PATCH] signal handling: revert sigkill priority fix
This patch reverts commit c33880aadd since
it's not needed anymore. As pointed out by Roland McGrath the real fix
is to deliver all signals before returning to user space.
See http://www.ussg.iu.edu/hypermail/linux/kernel/0509.2/0683.html
A fix for s390 has been merged.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:15 -08:00
Oleg Nesterov
7ed0175a46 [PATCH] Don't auto-reap traced children
If a task is being traced we never auto-reap it even if it might look
like its parent doesn't care. The tracer obviously _does_ care.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-10 09:57:19 -08:00
Paul E. McKenney
b0423a0d9c [PATCH] Remove duplicate code in signal.c
Combine a bit of redundant code between force_sig_info() and
force_sig_specific().

Signed-off-by: paulmck@us.ibm.com
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:32 -08:00
Oleg Nesterov
ae6866c377 [PATCH] remove unneeded SI_TIMER checks
This patch removes checks for ->si_code == SI_TIMER from send_signal,
specific_send_sig_info, __group_send_sig_info.

I think posix-timers.c used these functions some time ago, now it sends
signals via send_{,group_}sigqueue, so these hooks are unneeded.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:32 -08:00
Oleg Nesterov
621d31219d [PATCH] cleanup the usage of SEND_SIG_xxx constants
This patch simplifies some checks for magic siginfo values.  It should not
change the behaviour in any way.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:31 -08:00
Oleg Nesterov
b67a1b9e4b [PATCH] remove hardcoded SEND_SIG_xxx constants
This patch replaces hardcoded SEND_SIG_xxx constants with
their symbolic names.

No changes in affected .o files.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:31 -08:00
Andrea Arcangeli
30e0fca6c1 [PATCH] ptrace/coredump/exit_group deadlock
I could seldom reproduce a deadlock with a task not killable in T state
(TASK_STOPPED, not TASK_TRACED) by attaching a NPTL threaded program to
gdb, by segfaulting the task and triggering a core dump while some other
task is executing exit_group and while one task is in ptrace_attached
TASK_STOPPED state (not TASK_TRACED yet).  This originated from a gdb
bugreport (the fact gdb was segfaulting the task wasn't a kernel bug), but
I just incidentally noticed the gdb bug triggered a real kernel bug as
well.

Most threads hangs in exit_mm because the core_dumping is still going, the
core dumping hangs because the stopped task doesn't exit, the stopped task
can't wakeup because it has SIGNAL_GROUP_EXIT set, hence the deadlock.

To me it seems that the problem is that the force_sig_specific(SIGKILL) in
zap_threads is a noop if the task has PF_PTRACED set (like in this case
because gdb is attached).  The __ptrace_unlink does nothing because the
signal->flags is set to SIGNAL_GROUP_EXIT|SIGNAL_STOP_DEQUEUED (verified).

The above info also shows that the stopped task hit a race and got the stop
signal (presumably by the ptrace_attach, only the attach, state is still
TASK_STOPPED and gdb hangs waiting the core before it can set it to
TASK_TRACED) after one of the thread invoked the core dump (it's the core
dump that sets signal->flags to SIGNAL_GROUP_EXIT).

So beside the fact nobody would wakeup the task in __ptrace_unlink (the
state is _not_ TASK_TRACED), there's a secondary problem in the signal
handling code, where a task should ignore the ptrace-sigstops as long as
SIGNAL_GROUP_EXIT is set (or the wakeup in __ptrace_unlink path wouldn't be
enough).

So I attempted to make this patch that seems to fix the problem.  There
were various ways to fix it, perhaps you prefer a different one, I just
opted to the one that looked safer to me.

I also removed the clearing of the stopped bits from the zap_other_threads
(zap_other_threads was safe unlike zap_threads).  I don't like useless
code, this whole NPTL signal/ptrace thing is already unreadable enough and
full of corner cases without confusing useless code into it to make it even
less readable.  And if this code is really needed, then you may want to
explain why it's not being done in the other paths that sets
SIGNAL_GROUP_EXIT at least.

Even after this patch I still wonder who serializes the read of
p->ptrace in zap_threads.

Patch is called ptrace-core_dump-exit_group-deadlock-1.

This was the trace I've got:

test          T ffff81003e8118c0     0 14305      1         14311 14309 (NOTLB)
ffff810058ccdde8 0000000000000082 000001f4000037e1 ffff810000000013
       00000000000000f8 ffff81003e811b00 ffff81003e8118c0 ffff810011362100
       0000000000000012 ffff810017ca4180
Call Trace:<ffffffff801317ed>{try_to_wake_up+893} <ffffffff80141677>{finish_stop+87}
       <ffffffff8014367f>{get_signal_to_deliver+1359} <ffffffff8010d3ad>{do_signal+157}
       <ffffffff8013deee>{ptrace_check_attach+222} <ffffffff80111575>{sys_ptrace+2293}
       <ffffffff80131810>{default_wake_function+0} <ffffffff80196399>{sys_ioctl+73}
       <ffffffff8010dd27>{sysret_signal+28} <ffffffff8010e00f>{ptregscall_common+103}

test          D ffff810011362100     0 14309      1         14305 14312 (NOTLB)
ffff810053c81cf8 0000000000000082 0000000000000286 0000000000000001
       0000000000000195 ffff810011362340 ffff810011362100 ffff81002e338040
       ffff810001e0ca80 0000000000000001
Call Trace:<ffffffff801317ed>{try_to_wake_up+893} <ffffffff8044677d>{wait_for_completion+173}
       <ffffffff80131810>{default_wake_function+0} <ffffffff80137435>{exit_mm+149}
       <ffffffff801381af>{do_exit+479} <ffffffff80138d0c>{do_group_exit+252}
       <ffffffff801436db>{get_signal_to_deliver+1451} <ffffffff8010d3ad>{do_signal+157}
       <ffffffff8013deee>{ptrace_check_attach+222} <ffffffff80140850>{specific_send_sig_info+2

       <ffffffff8014208a>{force_sig_info+186} <ffffffff804479a0>{do_int3+112}
       <ffffffff8010e308>{retint_signal+61}
test          D ffff81002e338040     0 14311      1         14716 14305 (NOTLB)
ffff81005ca8dcf8 0000000000000082 0000000000000286 0000000000000001
       0000000000000120 ffff81002e338280 ffff81002e338040 ffff8100481cb740
       ffff810001e0ca80 0000000000000001
Call Trace:<ffffffff801317ed>{try_to_wake_up+893} <ffffffff8044677d>{wait_for_completion+173}
       <ffffffff80131810>{default_wake_function+0} <ffffffff80137435>{exit_mm+149}
       <ffffffff801381af>{do_exit+479} <ffffffff80142d0e>{__dequeue_signal+558}
       <ffffffff80138d0c>{do_group_exit+252} <ffffffff801436db>{get_signal_to_deliver+1451}
       <ffffffff8010d3ad>{do_signal+157} <ffffffff8013deee>{ptrace_check_attach+222}
       <ffffffff80140850>{specific_send_sig_info+208} <ffffffff8014208a>{force_sig_info+186}
       <ffffffff804479a0>{do_int3+112} <ffffffff8010e308>{retint_signal+61}

test          D ffff810017ca4180     0 14312      1         14309 13882 (NOTLB)
ffff81005d15fcb8 0000000000000082 ffff81005d15fc58 ffffffff80130816
       0000000000000897 ffff810017ca43c0 ffff810017ca4180 ffff81003e8118c0
       0000000000000082 ffffffff801317ed
Call Trace:<ffffffff80130816>{activate_task+150} <ffffffff801317ed>{try_to_wake_up+893}
       <ffffffff8044677d>{wait_for_completion+173} <ffffffff80131810>{default_wake_function+0}
       <ffffffff8018cdc3>{do_coredump+819} <ffffffff80445f52>{thread_return+82}
       <ffffffff801436d4>{get_signal_to_deliver+1444} <ffffffff8010d3ad>{do_signal+157}
       <ffffffff8013deee>{ptrace_check_attach+222} <ffffffff80140850>{specific_send_sig_info+2

       <ffffffff804472e5>{_spin_unlock_irqrestore+5} <ffffffff8014208a>{force_sig_info+186}
       <ffffffff804476ff>{do_general_protection+159} <ffffffff8010e308>{retint_signal+61}

Signed-off-by: Andrea Arcangeli <andrea@suse.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:22 -08:00
Vadim Lobanov
6dd69f1061 [PATCH] Unify sys_tkill() and sys_tgkill()
The majority of the sys_tkill() and sys_tgkill() function code is
duplicated between the two of them.  This patch pulls the duplication out
into a separate function -- do_tkill() -- and lets sys_tkill() and
sys_tgkill() be simple wrappers around it.  This should make it easier to
maintain in light of future changes.

Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:19 -08:00
Oleg Nesterov
19a4fcb531 [PATCH] kill sigqueue->lock
This lock is used in sigqueue_free(), but it is always equal to
current->sighand->siglock, so we don't need to keep it in the struct
sigqueue.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:19 -08:00
Oleg Nesterov
8d027de54c [PATCH] fix ->signal->live leak in copy_process()
exit_signal() (called from copy_process's error path) should decrement
->signal->live, otherwise forking process will miss 'group_dead' in
do_exit().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 10:28:13 -07:00
Roland McGrath
25f407f0b6 [PATCH] Call exit_itimers from do_exit, not __exit_signal
When I originally moved exit_itimers into __exit_signal, that was the only
place where we could reliably know it was the last thread in the group
dying, without races.  Since then we've gotten the signal_struct.live
counter, and do_exit can reliably do group-wide cleanup work.

This patch moves the call to do_exit, where it's made without locks.  This
avoids the deadlock issues that the old __exit_signal code's comment talks
about, and the one that Oleg found recently with process CPU timers.

[ This replaces e03d13e985, which is why
  it was just reverted. ]

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-21 15:38:08 -07:00
Harald Welte
46113830a1 [PATCH] Fix signal sending in usbdevio on async URB completion
If a process issues an URB from userspace and (starts to) terminate
before the URB comes back, we run into the issue described above.  This
is because the urb saves a pointer to "current" when it is posted to the
device, but there's no guarantee that this pointer is still valid
afterwards.

In fact, there are three separate issues:

1) the pointer to "current" can become invalid, since the task could be
   completely gone when the URB completion comes back from the device.

2) Even if the saved task pointer is still pointing to a valid task_struct,
   task_struct->sighand could have gone meanwhile.

3) Even if the process is perfectly fine, permissions may have changed,
   and we can no longer send it a signal.

So what we do instead, is to save the PID and uid's of the process, and
introduce a new kill_proc_info_as_uid() function.

Signed-off-by: Harald Welte <laforge@gnumonks.org>
[ Fixed up types and added symbol exports ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 16:16:33 -07:00
Al Viro
dd0fc66fb3 [PATCH] gfp flags annotations - part 1
- added typedef unsigned int __nocast gfp_t;

 - replaced __nocast uses for gfp flags with gfp_t - it gives exactly
   the same warnings as far as sparse is concerned, doesn't change
   generated code (from gcc point of view we replaced unsigned int with
   typedef) and documents what's going on far better.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08 15:00:57 -07:00
Oleg Nesterov
788e05a67c [PATCH] fix do_coredump() vs SIGSTOP race
Let's suppose we have 2 threads in thread group:
	A - does coredump
	B - has pending SIGSTOP

thread A						thread B

do_coredump:						get_signal_to_deliver:

  lock(->sighand)
  ->signal->flags = SIGNAL_GROUP_EXIT
  unlock(->sighand)

							lock(->sighand)
							signr = dequeue_signal()
								->signal->flags |= SIGNAL_STOP_DEQUEUED
								return SIGSTOP;

							do_signal_stop:
							    unlock(->sighand)

  coredump_wait:

      zap_threads:
          lock(tasklist_lock)
          send SIGKILL to B
              // signal_wake_up() does nothing
          unlock(tasklist_lock)

							    lock(tasklist_lock)
							    lock(->sighand)
							    re-check sig->flags & SIGNAL_STOP_DEQUEUED, yes
							    set_current_state(TASK_STOPPED);
							    finish_stop:
							        schedule();
							            // ->state == TASK_STOPPED

      wait_for_completion(&startup_done)
         // waits for complete() from B,
         // ->state == TASK_UNINTERRUPTIBLE

We can't wake up 'B' in any way:

	SIGCONT will be ignored because handle_stop_signal() sees
	->signal->flags & SIGNAL_GROUP_EXIT.

	sys_kill(SIGKILL)->__group_complete_signal() will choose
	uninterruptible 'A', so it can't help.

	sys_tkill(B, SIGKILL) will be ignored by specific_send_sig_info()
	because B already has pending SIGKILL.

This scenario is not possbile if 'A' does do_group_exit(), because
it sets sig->flags = SIGNAL_GROUP_EXIT and delivers SIGKILL to
subthreads atomically, holding both tasklist_lock and sighand->lock.
That means that do_signal_stop() will notice !SIGNAL_STOP_DEQUEUED
after re-locking ->sighand. And it is not possible to any other
thread to re-add SIGNAL_STOP_DEQUEUED later, because dequeue_signal()
can only return SIGKILL.

I think it is better to change do_coredump() to do sigaddset(SIGKILL)
and signal_wake_up() under sighand->lock, but this patch is much
simpler.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08 14:53:31 -07:00
Roland McGrath
5acbc5cb50 [PATCH] Fix task state testing properly in do_signal_stop()
Any tests using < TASK_STOPPED or the like are left over from the time
when the TASK_ZOMBIE and TASK_DEAD bits were in the same word, and it
served to check for "stopped or dead".  I think this one in
do_signal_stop is the only such case.  It has been buggy ever since
exit_state was separated, and isn't testing the exit_state value.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-29 15:20:47 -07:00
Linus Torvalds
188a1eafa0 Make sure SIGKILL gets proper respect
Bhavesh P. Davda <bhavesh@avaya.com> noticed that SIGKILL wouldn't
properly kill a process under just the right cicumstances: a stopped
task that already had another signal queued would get the SIGKILL
queued onto the shared queue, and there it would remain until SIGCONT.

This simplifies the signal acceptance logic, and fixes the bug in the
process.

Losely based on an earlier patch by Bhavesh.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-23 13:22:21 -07:00
Nishanth Aravamudan
75bcc8c5e1 [PATCH] kernel: fix-up schedule_timeout() usage
Use schedule_timeout_{,un}interruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 10:06:37 -07:00
Oleg Nesterov
e752dd6cc6 [PATCH] fix send_sigqueue() vs thread exit race
posix_timer_event() first checks that the thread (SIGEV_THREAD_ID case)
does not have PF_EXITING flag, then it calls send_sigqueue() which locks
task list.  But if the thread exits in between the kernel will oops
(->sighand == NULL after __exit_sighand).

This patch moves the PF_EXITING check into the send_sigqueue(), it must be
done atomically under tasklist_lock.  When send_sigqueue() detects exiting
thread it returns -1.  In that case posix_timer_event will send the signal
to thread group.

Also, this patch fixes task_struct use-after-free in posix_timer_event.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:33 -07:00
Oleg Nesterov
bc505a478d [PATCH] do_notify_parent_cldstop() cleanup
This patch simplifies the usage of do_notify_parent_cldstop(), it lessens
the source and .text size slightly, and makes the code (in my opinion) a
bit more readable.

I am sending this patch now because I'm afraid Paul will touch
do_notify_parent_cldstop() really soon, It's better to cleanup first.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:31 -07:00
Bhavesh P. Davda
dd12f48d4e [PATCH] NPTL signal delivery deadlock fix
This bug is quite subtle and only happens in a very interesting
situation where a real-time threaded process is in the middle of a
coredump when someone whacks it with a SIGKILL.  However, this deadlock
leaves the system pretty hosed and you have to reboot to recover.

Not good for real-time priority-preemption applications like our
telephony application, with 90+ real-time (SCHED_FIFO and SCHED_RR)
processes, many of them multi-threaded, interacting with each other for
high volume call processing.

Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-17 12:52:04 -07:00
Christoph Lameter
3e1d1d28d9 [PATCH] Cleanup patch for process freezing
1. Establish a simple API for process freezing defined in linux/include/sched.h:

   frozen(process)		Check for frozen process
   freezing(process)		Check if a process is being frozen
   freeze(process)		Tell a process to freeze (go to refrigerator)
   thaw_process(process)	Restart process
   frozen_process(process)	Process is frozen now

2. Remove all references to PF_FREEZE and PF_FROZEN from all
   kernel sources except sched.h

3. Fix numerous locations where try_to_freeze is manually done by a driver

4. Remove the argument that is no longer necessary from two function calls.

5. Some whitespace cleanup

6. Clear potential race in refrigerator (provides an open window of PF_FREEZE
   cleared before setting PF_FROZEN, recalc_sigpending does not check
   PF_FROZEN).

This patch does not address the problem of freeze_processes() violating the rule
that a task may only modify its own flags by setting PF_FREEZE. This is not clean
in an SMP environment. freeze(process) is therefore not SMP safe!

Signed-off-by: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 17:10:13 -07:00
Kirill Korotaev
4fea2838aa [PATCH] Software suspend and recalc sigpending bug fix
This patch fixes recalc_sigpending() to work correctly with tasks which are
being freezed.

The problem is that freeze_processes() sets PF_FREEZE and TIF_SIGPENDING
flags on tasks, but recalc_sigpending() called from e.g.
sys_rt_sigtimedwait or any other kernel place will clear TIF_SIGPENDING due
to no pending signals queued and the tasks won't be freezed until it
recieves a real signal or freezed_processes() fail due to timeout.

Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Signed-Off-By: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:27 -07:00
David Woodhouse
1c3f45ab2f Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.git 2005-06-02 16:39:11 +01:00
Kirill Korotaev
c33880aadd [PATCH] sigkill priority fix
If SIGKILL does not have priority, we cannot instantly kill task before it
makes some unexpected job.  It can be critical, but we were unable to
reproduce this easily until Heiko Carstens <Heiko.Carstens@de.ibm.com>
reported this problem on LKML.

Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Signed-Off-By: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-24 20:08:13 -07:00
Steve Grubb
c2f0c7c356 The attached patch addresses the problem with getting the audit daemon
shutdown credential information. It creates a new message type 
AUDIT_TERM_INFO, which is used by the audit daemon to query who issued the 
shutdown. 

It requires the placement of a hook function that gathers the information. The 
hook is after the DAC & MAC checks and before the function returns. Racing 
threads could overwrite the uid & pid - but they would have to be root and 
have policy that allows signalling the audit daemon. That should be a 
manageable risk.

The userspace component will be released later in audit 0.7.2. When it 
receives the TERM signal, it queries the kernel for shutdown information. 
When it receives it, it writes the message and exits. The message looks 
like this:

type=DAEMON msg=auditd(1114551182.000) auditd normal halt, sending pid=2650 
uid=525, auditd pid=1685

Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06 12:38:39 +01:00
Jesper Juhl
7ed20e1ad5 [PATCH] convert that currently tests _NSIG directly to use valid_signal()
Convert most of the current code that uses _NSIG directly to instead use
valid_signal().  This avoids gcc -W warnings and off-by-one errors.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:14 -07:00
Christoph Hellwig
6cae60feb6 [PATCH] kill #ifndef HAVE_ARCH_GET_SIGNAL_TO_DELIVER in signal.c
Now that no architectures defines HAVE_ARCH_GET_SIGNAL_TO_DELIVER anymore
this can go away.  It was a transitional hack only.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16 15:25:47 -07:00
Linus Torvalds
1da177e4c3 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!
2005-04-16 15:20:36 -07:00