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* fix bogus reporting of signals by auditAl Viro2007-10-071-11/+11
| | | | | | | | | | | | | | | | | | | | Async signals should not be reported as sent by current in audit log. As it is, we call audit_signal_info() too early in check_kill_permission(). Note that check_kill_permission() has that test already - it needs to know if it should apply current-based permission checks. So the solution is to move the call of audit_signal_info() between those. Bogosity in question is easily reproduced - add a rule watching for e.g. kill(2) from specific process (so that audit_signal_info() would not short-circuit to nothing), say load_policy, watch the bogus OBJ_PID entry in audit logs claiming that write(2) on selinuxfs file issued by load_policy(8) had somehow managed to send a signal to syslogd... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Steve Grubb <sgrubb@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* signalfd simplificationDavide Libenzi2007-09-201-5/+3
| | | | | | | | | | | | | | | | | | | | This simplifies signalfd code, by avoiding it to remain attached to the sighand during its lifetime. In this way, the signalfd remain attached to the sighand only during poll(2) (and select and epoll) and read(2). This also allows to remove all the custom "tsk == current" checks in kernel/signal.c, since dequeue_signal() will only be called by "current". I think this is also what Ben was suggesting time ago. The external effect of this, is that a thread can extract only its own private signals and the group ones. I think this is an acceptable behaviour, in that those are the signals the thread would be able to fetch w/out signalfd. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sigqueue_free: fix the race with collect_signal()Oleg Nesterov2007-08-311-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Spotted by taoyue <yue.tao@windriver.com> and Jeremy Katz <jeremy.katz@windriver.com>. collect_signal: sigqueue_free: list_del_init(&first->list); if (!list_empty(&q->list)) { // not taken } q->flags &= ~SIGQUEUE_PREALLOC; __sigqueue_free(first); __sigqueue_free(q); Now, __sigqueue_free() is called twice on the same "struct sigqueue" with the obviously bad implications. In particular, this double free breaks the array_cache->avail logic, so the same sigqueue could be "allocated" twice, and the bug can manifest itself via the "impossible" BUG_ON(!SIGQUEUE_PREALLOC) in sigqueue_free/send_sigqueue. Hopefully this can explain these mysterious bug-reports, see http://marc.info/?t=118766926500003 http://marc.info/?t=118466273000005 Alexey Dobriyan reports this patch makes the difference for the testcase, but nobody has an access to the application which opened the problems originally. Also, this patch removes tasklist lock/unlock, ->siglock is enough. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: taoyue <yue.tao@windriver.com> Cc: Jeremy Katz <jeremy.katz@windriver.com> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Alexey Dobriyan <adobriyan@sw.ru> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Roland McGrath <roland@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* signalfd: fix interaction with posix-timersOleg Nesterov2007-08-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dequeue_signal: if (__SI_TIMER) { spin_unlock(&tsk->sighand->siglock); do_schedule_next_timer(info); spin_lock(&tsk->sighand->siglock); } Unless tsk == curent, this is absolutely unsafe: nothing prevents tsk from exiting. If signalfd was passed to another process, do_schedule_next_timer() is just wrong. Add yet another "tsk == current" check into dequeue_signal(). This patch fixes an oopsable bug, but breaks the scheduling of posix timers if the shared __SI_TIMER signal was fetched via signalfd attached to another sub-thread. Mostly fixed by the next patch. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Michael Kerrisk <mtk-manpages@gmx.net> Cc: Roland McGrath <roland@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Kill some obsolete sub-thread-ptrace stuffOleg Nesterov2007-08-031-4/+0
| | | | | | | | | | | | | | There is a couple of subtle checks which were needed to handle ptracing from the same thread group. This was deprecated a long ago, imho this code just complicates the understanding. And, the "->parent->signal->flags & SIGNAL_GROUP_EXIT" check in exit_notify() is not right. SIGNAL_GROUP_EXIT can mean exec(), not exit_group(). This means ptracer can lose a ptraced zombie on exec(). Minor problem, but still the bug. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: i386-show-unhandled-signals-v3Masoud Asgharifard Sharbiani2007-07-221-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes the i386 behave the same way that x86_64 does when a segfault happens. A line gets printed to the kernel log so that tools that need to check for failures can behave more uniformly between debug.show_unhandled_signals sysctl variable to 0 (or by doing echo 0 > /proc/sys/debug/exception-trace) Also, all of the lines being printed are now using printk_ratelimit() to deny the ability of DoS from a local user with a program like the following: main() { while (1) if (!fork()) *(int *)0 = 0; } This new revision also includes the fix that Andrew did which got rid of new sysctl that was added to the system in earlier versions of this. Also, 'show-unhandled-signals' sysctl has been renamed back to the old 'exception-trace' to avoid breakage of people's scripts. AK: Enabling by default for i386 will be likely controversal, but let's see what happens AK: Really folks, before complaining just fix your segfaults AK: I bet this will find a lot of silent issues Signed-off-by: Masoud Sharbiani <masouds@google.com> Signed-off-by: Andi Kleen <ak@suse.de> [ Personally, I've found the complaints useful on x86-64, so I'm all for this. That said, I wonder if we could do it more prettily.. -Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vdso: print fatal signalsIngo Molnar2007-07-161-0/+33
| | | | | | | | | | | | | | | | | Add the print-fatal-signals=1 boot option and the /proc/sys/kernel/print-fatal-signals runtime switch. This feature prints some minimal information about userspace segfaults to the kernel console. This is useful to find early bootup bugs where userspace debugging is very hard. Defaults to off. [akpm@linux-foundation.org: Don't add new sysctl numbers] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Fix signalfd interaction with thread-private signalsBenjamin Herrenschmidt2007-06-181-1/+7
| | | | | | | | | | | Don't let signalfd dequeue private signals off other threads (in the case of things like SIGILL or SIGSEGV, trying to do so would result in undefined behaviour on who actually gets the signal, since they are force unblocked). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Restrict clearing TIF_SIGPENDINGRoland McGrath2007-06-071-4/+12
| | | | | | | | | | | | | | | | This patch should get a few birds. It prevents sigaction calls from clearing TIF_SIGPENDING in other threads, which could leak -ERESTART*. And It fixes ptrace_stop not to clear it, which done at the syscall exit stop could leak -ERESTART*. It probably removes the harm from signalfd, at least assuming it never calls dequeue_signal on kernel threads that might have used block_all_signals. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* recalc_sigpending_tsk fixesRoland McGrath2007-05-231-6/+18
| | | | | | | | | | | | | | | | | | | Steve Hawkes discovered a problem where recalc_sigpending_tsk was called in do_sigaction but no signal_wake_up call was made, preventing later signals from waking up blocked threads with TIF_SIGPENDING already set. In fact, the few other calls to recalc_sigpending_tsk outside the signals code are also subject to this problem in other race conditions. This change makes recalc_sigpending_tsk private to the signals code. It changes the outside calls, as well as do_sigaction, to use the new recalc_sigpending_and_wake instead. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: <Steve.Hawkes@motorola.com> 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>
* Merge branch 'audit.b38' of ↵Linus Torvalds2007-05-111-4/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * [PATCH] audit signal recipientsAmy Griffis2007-05-111-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | signal/timer/event: signalfd coreDavide Libenzi2007-05-111-2/+20
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* change kernel threads to ignore signals instead of blocking themOleg Nesterov2007-05-091-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* zap_other_threads: remove unneeded ->exit_signal changeOleg Nesterov2007-05-091-11/+0
| | | | | | | | | 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>
* Move sig_kernel_* et al macros to linux/signal.hRoland McGrath2007-05-091-119/+0
| | | | | | | | | | | 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>
* header cleaning: don't include smp_lock.h when not usedRandy Dunlap2007-05-081-1/+0
| | | | | | | | | | | | 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>
* KMEM_CACHE(): simplify slab cache creationChristoph Lameter2007-05-071-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6Linus Torvalds2007-02-261-1/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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.
| * Revert "[PATCH] make kernel/signal.c:kill_proc_info() static"Matthew Wilcox2007-02-171-1/+2
| | | | | | | | | | | | | | This reverts commit d3228a887cae75ef2b8b1211c31c539bef5a5698. DeBunk this code. We need it for compat_sys_rt_sigqueueinfo. Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* | [PATCH] hrtimers: prevent possible itimer DoSThomas Gleixner2007-02-161-17/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | [PATCH] pid: remove the now unused kill_pg kill_pg_info and __kill_pg_infoEric W. Biederman2007-02-121-27/+0
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | [PATCH] pid: replace is_orphaned_pgrp with is_current_pgrp_orphanedEric W. Biederman2007-02-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | [PATCH] signal: rewrite kill_something_info so it uses newer helpersEric W. Biederman2007-02-121-4/+8
| | | | | | | | | | | | | | | | | | | | | | 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>
* | [PATCH] Numerous fixes to kernel-doc info in source files.Robert P. J. Day2007-02-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | [PATCH] kill_pid_info: kill acquired_tasklist_lockOleg Nesterov2007-02-111-5/+4
|/ | | | | | | | | 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>
* [PATCH] PM: Fix freezing of stopped tasksRafael J. Wysocki2006-12-131-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] add child reaper to pid_namespaceSukadev Bhattiprolu2006-12-081-2/+9
| | | | | | | | | | | | | | | | | 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>
* [PATCH] add process_session() helper routineCedric Le Goater2006-12-081-1/+1
| | | | | | | | | | | | | | | 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>
* [PATCH] make kernel/signal.c:kill_proc_info() staticAdrian Bunk2006-12-071-2/+1
| | | | | | Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Add include/linux/freezer.h and move definitions from sched.hNigel Cunningham2006-12-071-0/+1
| | | | | | | | | | | | | 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>
* [PATCH] slab: remove kmem_cache_tChristoph Lameter2006-12-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Make sure "user->sigpending" count is in syncLinus Torvalds2006-11-041-4/+11
| | | | | | | | | | | | | | | | | | | | | | | | | The previous commit (45c18b0bb579b5c1b89f8c99f1b6ffa4c586ba08, 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>
* [PATCH] usb: fixup usb so it uses struct pidEric W. Biederman2006-10-021-4/+4
| | | | | | | | | | | | | | | | 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>
* [PATCH] pid: implement signal functions that take a struct pid *Eric W. Biederman2006-10-021-10/+47
| | | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] __dequeue_signal() cleanupRoland McGrath2006-09-291-4/+2
| | | | | | | | | | | 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>
* [PATCH] NOMMU: move the fallback arch_vma_name() to a sensible placeDavid Howells2006-09-271-0/+5
| | | | | | | | | | | | | 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>
* Fix force_sig_info() semantics after cleanupsLinus Torvalds2006-08-021-8/+17
| | | | | | | | | | | | | | Suresh points out that commit b0423a0d9cc836b2c3d796623cd19236bfedfe63 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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds2006-06-301-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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
| * Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | | | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* | [PATCH] SELinux: add security hook call to kill_proc_info_as_uidDavid Quigley2006-06-301-2/+5
|/ | | | | | | | | | | | | | 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>
* [PATCH] coredump: kill ptrace related stuffOleg Nesterov2006-06-261-5/+30
| | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] collect sid of those who send signals to auditdAl Viro2006-06-201-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [PATCH] fix non-leader exec under ptraceRoland McGrath2006-04-141-2/+2
| | | | | | | | | | | This reverts most of commit 30e0fca6c1d7d26f3f2daa4dd2b12c51dadc778a. 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 788e05a67c343fa22f2ae1d3ca264e7f15c25eaf. Signed-off-by: Roland McGrath <roland@redhat.com> Acked-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] __group_complete_signal: remove bogus BUG_ONOleg Nesterov2006-04-111-1/+0
| | | | | | | | | | | | Commit e56d090310d7625ecb43a1eeebd479f04affb48b [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>
* BUG_ON() Conversion in kernel/signal.cEric Sesterhenn2006-04-021-4/+2
| | | | | | | | 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>
* [PATCH] Fix suspend with traced tasksPavel Machek2006-03-311-0/+1
| | | | | | | | | | | 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>
* [PATCH] send_sigqueue: simplify and fix the raceOleg Nesterov2006-03-281-37/+4
| | | | | | | | | | | | | | | | 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>
* [PATCH] do_notify_parent_cldstop: remove 'to_self' paramOleg Nesterov2006-03-281-21/+11
| | | | | | | | | | | 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>
* [PATCH] finish_stop: don't check stop_count < 0Oleg Nesterov2006-03-281-1/+1
| | | | | | | | | | 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>
generated by cgit v1.1 at 2024-12-27 08:34:49 +0000