2 * linux/kernel/signal.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
6 * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson
8 * 2003-06-02 Jim Houston - Concurrent Computer Corp.
9 * Changes to use preallocated sigqueue structures
10 * to allow signals to be sent reliably.
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/sched.h>
18 #include <linux/tty.h>
19 #include <linux/binfmts.h>
20 #include <linux/security.h>
21 #include <linux/syscalls.h>
22 #include <linux/ptrace.h>
23 #include <linux/signal.h>
24 #include <linux/signalfd.h>
25 #include <linux/capability.h>
26 #include <linux/freezer.h>
27 #include <linux/pid_namespace.h>
28 #include <linux/nsproxy.h>
30 #include <asm/param.h>
31 #include <asm/uaccess.h>
32 #include <asm/unistd.h>
33 #include <asm/siginfo.h>
34 #include "audit.h" /* audit_signal_info() */
37 * SLAB caches for signal bits.
40 static struct kmem_cache
*sigqueue_cachep
;
42 static int __sig_ignored(struct task_struct
*t
, int sig
)
46 /* Is it explicitly or implicitly ignored? */
48 handler
= t
->sighand
->action
[sig
- 1].sa
.sa_handler
;
49 return handler
== SIG_IGN
||
50 (handler
== SIG_DFL
&& sig_kernel_ignore(sig
));
53 static int sig_ignored(struct task_struct
*t
, int sig
)
56 * Tracers always want to know about signals..
58 if (t
->ptrace
& PT_PTRACED
)
62 * Blocked signals are never ignored, since the
63 * signal handler may change by the time it is
66 if (sigismember(&t
->blocked
, sig
) || sigismember(&t
->real_blocked
, sig
))
69 return __sig_ignored(t
, sig
);
73 * Re-calculate pending state from the set of locally pending
74 * signals, globally pending signals, and blocked signals.
76 static inline int has_pending_signals(sigset_t
*signal
, sigset_t
*blocked
)
81 switch (_NSIG_WORDS
) {
83 for (i
= _NSIG_WORDS
, ready
= 0; --i
>= 0 ;)
84 ready
|= signal
->sig
[i
] &~ blocked
->sig
[i
];
87 case 4: ready
= signal
->sig
[3] &~ blocked
->sig
[3];
88 ready
|= signal
->sig
[2] &~ blocked
->sig
[2];
89 ready
|= signal
->sig
[1] &~ blocked
->sig
[1];
90 ready
|= signal
->sig
[0] &~ blocked
->sig
[0];
93 case 2: ready
= signal
->sig
[1] &~ blocked
->sig
[1];
94 ready
|= signal
->sig
[0] &~ blocked
->sig
[0];
97 case 1: ready
= signal
->sig
[0] &~ blocked
->sig
[0];
102 #define PENDING(p,b) has_pending_signals(&(p)->signal, (b))
104 static int recalc_sigpending_tsk(struct task_struct
*t
)
106 if (t
->signal
->group_stop_count
> 0 ||
107 PENDING(&t
->pending
, &t
->blocked
) ||
108 PENDING(&t
->signal
->shared_pending
, &t
->blocked
)) {
109 set_tsk_thread_flag(t
, TIF_SIGPENDING
);
113 * We must never clear the flag in another thread, or in current
114 * when it's possible the current syscall is returning -ERESTART*.
115 * So we don't clear it here, and only callers who know they should do.
121 * After recalculating TIF_SIGPENDING, we need to make sure the task wakes up.
122 * This is superfluous when called on current, the wakeup is a harmless no-op.
124 void recalc_sigpending_and_wake(struct task_struct
*t
)
126 if (recalc_sigpending_tsk(t
))
127 signal_wake_up(t
, 0);
130 void recalc_sigpending(void)
132 if (!recalc_sigpending_tsk(current
) && !freezing(current
))
133 clear_thread_flag(TIF_SIGPENDING
);
137 /* Given the mask, find the first available signal that should be serviced. */
139 int next_signal(struct sigpending
*pending
, sigset_t
*mask
)
141 unsigned long i
, *s
, *m
, x
;
144 s
= pending
->signal
.sig
;
146 switch (_NSIG_WORDS
) {
148 for (i
= 0; i
< _NSIG_WORDS
; ++i
, ++s
, ++m
)
149 if ((x
= *s
&~ *m
) != 0) {
150 sig
= ffz(~x
) + i
*_NSIG_BPW
+ 1;
155 case 2: if ((x
= s
[0] &~ m
[0]) != 0)
157 else if ((x
= s
[1] &~ m
[1]) != 0)
164 case 1: if ((x
= *s
&~ *m
) != 0)
172 static struct sigqueue
*__sigqueue_alloc(struct task_struct
*t
, gfp_t flags
,
175 struct sigqueue
*q
= NULL
;
176 struct user_struct
*user
;
179 * In order to avoid problems with "switch_user()", we want to make
180 * sure that the compiler doesn't re-load "t->user"
184 atomic_inc(&user
->sigpending
);
185 if (override_rlimit
||
186 atomic_read(&user
->sigpending
) <=
187 t
->signal
->rlim
[RLIMIT_SIGPENDING
].rlim_cur
)
188 q
= kmem_cache_alloc(sigqueue_cachep
, flags
);
189 if (unlikely(q
== NULL
)) {
190 atomic_dec(&user
->sigpending
);
192 INIT_LIST_HEAD(&q
->list
);
194 q
->user
= get_uid(user
);
199 static void __sigqueue_free(struct sigqueue
*q
)
201 if (q
->flags
& SIGQUEUE_PREALLOC
)
203 atomic_dec(&q
->user
->sigpending
);
205 kmem_cache_free(sigqueue_cachep
, q
);
208 void flush_sigqueue(struct sigpending
*queue
)
212 sigemptyset(&queue
->signal
);
213 while (!list_empty(&queue
->list
)) {
214 q
= list_entry(queue
->list
.next
, struct sigqueue
, list
);
215 list_del_init(&q
->list
);
221 * Flush all pending signals for a task.
223 void flush_signals(struct task_struct
*t
)
227 spin_lock_irqsave(&t
->sighand
->siglock
, flags
);
228 clear_tsk_thread_flag(t
, TIF_SIGPENDING
);
229 flush_sigqueue(&t
->pending
);
230 flush_sigqueue(&t
->signal
->shared_pending
);
231 spin_unlock_irqrestore(&t
->sighand
->siglock
, flags
);
234 void ignore_signals(struct task_struct
*t
)
238 for (i
= 0; i
< _NSIG
; ++i
)
239 t
->sighand
->action
[i
].sa
.sa_handler
= SIG_IGN
;
245 * Flush all handlers for a task.
249 flush_signal_handlers(struct task_struct
*t
, int force_default
)
252 struct k_sigaction
*ka
= &t
->sighand
->action
[0];
253 for (i
= _NSIG
; i
!= 0 ; i
--) {
254 if (force_default
|| ka
->sa
.sa_handler
!= SIG_IGN
)
255 ka
->sa
.sa_handler
= SIG_DFL
;
257 sigemptyset(&ka
->sa
.sa_mask
);
262 int unhandled_signal(struct task_struct
*tsk
, int sig
)
264 if (is_global_init(tsk
))
266 if (tsk
->ptrace
& PT_PTRACED
)
268 return (tsk
->sighand
->action
[sig
-1].sa
.sa_handler
== SIG_IGN
) ||
269 (tsk
->sighand
->action
[sig
-1].sa
.sa_handler
== SIG_DFL
);
273 /* Notify the system that a driver wants to block all signals for this
274 * process, and wants to be notified if any signals at all were to be
275 * sent/acted upon. If the notifier routine returns non-zero, then the
276 * signal will be acted upon after all. If the notifier routine returns 0,
277 * then then signal will be blocked. Only one block per process is
278 * allowed. priv is a pointer to private data that the notifier routine
279 * can use to determine if the signal should be blocked or not. */
282 block_all_signals(int (*notifier
)(void *priv
), void *priv
, sigset_t
*mask
)
286 spin_lock_irqsave(¤t
->sighand
->siglock
, flags
);
287 current
->notifier_mask
= mask
;
288 current
->notifier_data
= priv
;
289 current
->notifier
= notifier
;
290 spin_unlock_irqrestore(¤t
->sighand
->siglock
, flags
);
293 /* Notify the system that blocking has ended. */
296 unblock_all_signals(void)
300 spin_lock_irqsave(¤t
->sighand
->siglock
, flags
);
301 current
->notifier
= NULL
;
302 current
->notifier_data
= NULL
;
304 spin_unlock_irqrestore(¤t
->sighand
->siglock
, flags
);
307 static int collect_signal(int sig
, struct sigpending
*list
, siginfo_t
*info
)
309 struct sigqueue
*q
, *first
= NULL
;
310 int still_pending
= 0;
312 if (unlikely(!sigismember(&list
->signal
, sig
)))
316 * Collect the siginfo appropriate to this signal. Check if
317 * there is another siginfo for the same signal.
319 list_for_each_entry(q
, &list
->list
, list
) {
320 if (q
->info
.si_signo
== sig
) {
329 list_del_init(&first
->list
);
330 copy_siginfo(info
, &first
->info
);
331 __sigqueue_free(first
);
333 sigdelset(&list
->signal
, sig
);
336 /* Ok, it wasn't in the queue. This must be
337 a fast-pathed signal or we must have been
338 out of queue space. So zero out the info.
340 sigdelset(&list
->signal
, sig
);
341 info
->si_signo
= sig
;
350 static int __dequeue_signal(struct sigpending
*pending
, sigset_t
*mask
,
353 int sig
= next_signal(pending
, mask
);
356 if (current
->notifier
) {
357 if (sigismember(current
->notifier_mask
, sig
)) {
358 if (!(current
->notifier
)(current
->notifier_data
)) {
359 clear_thread_flag(TIF_SIGPENDING
);
365 if (!collect_signal(sig
, pending
, info
))
373 * Dequeue a signal and return the element to the caller, which is
374 * expected to free it.
376 * All callers have to hold the siglock.
378 int dequeue_signal(struct task_struct
*tsk
, sigset_t
*mask
, siginfo_t
*info
)
382 /* We only dequeue private signals from ourselves, we don't let
383 * signalfd steal them
385 signr
= __dequeue_signal(&tsk
->pending
, mask
, info
);
387 signr
= __dequeue_signal(&tsk
->signal
->shared_pending
,
392 * itimers are process shared and we restart periodic
393 * itimers in the signal delivery path to prevent DoS
394 * attacks in the high resolution timer case. This is
395 * compliant with the old way of self restarting
396 * itimers, as the SIGALRM is a legacy signal and only
397 * queued once. Changing the restart behaviour to
398 * restart the timer in the signal dequeue path is
399 * reducing the timer noise on heavy loaded !highres
402 if (unlikely(signr
== SIGALRM
)) {
403 struct hrtimer
*tmr
= &tsk
->signal
->real_timer
;
405 if (!hrtimer_is_queued(tmr
) &&
406 tsk
->signal
->it_real_incr
.tv64
!= 0) {
407 hrtimer_forward(tmr
, tmr
->base
->get_time(),
408 tsk
->signal
->it_real_incr
);
409 hrtimer_restart(tmr
);
418 if (unlikely(sig_kernel_stop(signr
))) {
420 * Set a marker that we have dequeued a stop signal. Our
421 * caller might release the siglock and then the pending
422 * stop signal it is about to process is no longer in the
423 * pending bitmasks, but must still be cleared by a SIGCONT
424 * (and overruled by a SIGKILL). So those cases clear this
425 * shared flag after we've set it. Note that this flag may
426 * remain set after the signal we return is ignored or
427 * handled. That doesn't matter because its only purpose
428 * is to alert stop-signal processing code when another
429 * processor has come along and cleared the flag.
431 if (!(tsk
->signal
->flags
& SIGNAL_GROUP_EXIT
))
432 tsk
->signal
->flags
|= SIGNAL_STOP_DEQUEUED
;
434 if ((info
->si_code
& __SI_MASK
) == __SI_TIMER
&& info
->si_sys_private
) {
436 * Release the siglock to ensure proper locking order
437 * of timer locks outside of siglocks. Note, we leave
438 * irqs disabled here, since the posix-timers code is
439 * about to disable them again anyway.
441 spin_unlock(&tsk
->sighand
->siglock
);
442 do_schedule_next_timer(info
);
443 spin_lock(&tsk
->sighand
->siglock
);
449 * Tell a process that it has a new active signal..
451 * NOTE! we rely on the previous spin_lock to
452 * lock interrupts for us! We can only be called with
453 * "siglock" held, and the local interrupt must
454 * have been disabled when that got acquired!
456 * No need to set need_resched since signal event passing
457 * goes through ->blocked
459 void signal_wake_up(struct task_struct
*t
, int resume
)
463 set_tsk_thread_flag(t
, TIF_SIGPENDING
);
466 * For SIGKILL, we want to wake it up in the stopped/traced/killable
467 * case. We don't check t->state here because there is a race with it
468 * executing another processor and just now entering stopped state.
469 * By using wake_up_state, we ensure the process will wake up and
470 * handle its death signal.
472 mask
= TASK_INTERRUPTIBLE
;
474 mask
|= TASK_WAKEKILL
;
475 if (!wake_up_state(t
, mask
))
480 * Remove signals in mask from the pending set and queue.
481 * Returns 1 if any signals were found.
483 * All callers must be holding the siglock.
485 * This version takes a sigset mask and looks at all signals,
486 * not just those in the first mask word.
488 static int rm_from_queue_full(sigset_t
*mask
, struct sigpending
*s
)
490 struct sigqueue
*q
, *n
;
493 sigandsets(&m
, mask
, &s
->signal
);
494 if (sigisemptyset(&m
))
497 signandsets(&s
->signal
, &s
->signal
, mask
);
498 list_for_each_entry_safe(q
, n
, &s
->list
, list
) {
499 if (sigismember(mask
, q
->info
.si_signo
)) {
500 list_del_init(&q
->list
);
507 * Remove signals in mask from the pending set and queue.
508 * Returns 1 if any signals were found.
510 * All callers must be holding the siglock.
512 static int rm_from_queue(unsigned long mask
, struct sigpending
*s
)
514 struct sigqueue
*q
, *n
;
516 if (!sigtestsetmask(&s
->signal
, mask
))
519 sigdelsetmask(&s
->signal
, mask
);
520 list_for_each_entry_safe(q
, n
, &s
->list
, list
) {
521 if (q
->info
.si_signo
< SIGRTMIN
&&
522 (mask
& sigmask(q
->info
.si_signo
))) {
523 list_del_init(&q
->list
);
531 * Bad permissions for sending the signal
533 static int check_kill_permission(int sig
, struct siginfo
*info
,
534 struct task_struct
*t
)
538 if (!valid_signal(sig
))
541 if (info
!= SEND_SIG_NOINFO
&& (is_si_special(info
) || SI_FROMKERNEL(info
)))
544 error
= audit_signal_info(sig
, t
); /* Let audit system see the signal */
548 if (((sig
!= SIGCONT
) || (task_session_nr(current
) != task_session_nr(t
)))
549 && (current
->euid
^ t
->suid
) && (current
->euid
^ t
->uid
)
550 && (current
->uid
^ t
->suid
) && (current
->uid
^ t
->uid
)
551 && !capable(CAP_KILL
))
554 return security_task_kill(t
, info
, sig
, 0);
558 static void do_notify_parent_cldstop(struct task_struct
*tsk
, int why
);
561 * Handle magic process-wide effects of stop/continue signals.
562 * Unlike the signal actions, these happen immediately at signal-generation
563 * time regardless of blocking, ignoring, or handling. This does the
564 * actual continuing for SIGCONT, but not the actual stopping for stop
565 * signals. The process stop is done as a signal action for SIG_DFL.
567 static void handle_stop_signal(int sig
, struct task_struct
*p
)
569 struct task_struct
*t
;
571 if (p
->signal
->flags
& SIGNAL_GROUP_EXIT
)
573 * The process is in the middle of dying already.
577 if (sig_kernel_stop(sig
)) {
579 * This is a stop signal. Remove SIGCONT from all queues.
581 rm_from_queue(sigmask(SIGCONT
), &p
->signal
->shared_pending
);
584 rm_from_queue(sigmask(SIGCONT
), &t
->pending
);
587 } else if (sig
== SIGCONT
) {
589 * Remove all stop signals from all queues,
590 * and wake all threads.
592 if (unlikely(p
->signal
->group_stop_count
> 0)) {
594 * There was a group stop in progress. We'll
595 * pretend it finished before we got here. We are
596 * obliged to report it to the parent: if the
597 * SIGSTOP happened "after" this SIGCONT, then it
598 * would have cleared this pending SIGCONT. If it
599 * happened "before" this SIGCONT, then the parent
600 * got the SIGCHLD about the stop finishing before
601 * the continue happened. We do the notification
602 * now, and it's as if the stop had finished and
603 * the SIGCHLD was pending on entry to this kill.
605 p
->signal
->group_stop_count
= 0;
606 p
->signal
->flags
= SIGNAL_STOP_CONTINUED
|
609 rm_from_queue(SIG_KERNEL_STOP_MASK
, &p
->signal
->shared_pending
);
613 rm_from_queue(SIG_KERNEL_STOP_MASK
, &t
->pending
);
616 * If there is a handler for SIGCONT, we must make
617 * sure that no thread returns to user mode before
618 * we post the signal, in case it was the only
619 * thread eligible to run the signal handler--then
620 * it must not do anything between resuming and
621 * running the handler. With the TIF_SIGPENDING
622 * flag set, the thread will pause and acquire the
623 * siglock that we hold now and until we've queued
624 * the pending signal.
626 * Wake up the stopped thread _after_ setting
629 state
= __TASK_STOPPED
;
630 if (sig_user_defined(t
, SIGCONT
) && !sigismember(&t
->blocked
, SIGCONT
)) {
631 set_tsk_thread_flag(t
, TIF_SIGPENDING
);
632 state
|= TASK_INTERRUPTIBLE
;
634 wake_up_state(t
, state
);
639 if (p
->signal
->flags
& SIGNAL_STOP_STOPPED
) {
641 * We were in fact stopped, and are now continued.
642 * Notify the parent with CLD_CONTINUED.
644 p
->signal
->flags
= SIGNAL_STOP_CONTINUED
|
645 SIGNAL_CLD_CONTINUED
;
646 p
->signal
->group_exit_code
= 0;
649 * We are not stopped, but there could be a stop
650 * signal in the middle of being processed after
651 * being removed from the queue. Clear that too.
653 p
->signal
->flags
&= ~SIGNAL_STOP_DEQUEUED
;
655 } else if (sig
== SIGKILL
) {
657 * Make sure that any pending stop signal already dequeued
658 * is undone by the wakeup for SIGKILL.
660 p
->signal
->flags
&= ~SIGNAL_STOP_DEQUEUED
;
664 static inline int legacy_queue(struct sigpending
*signals
, int sig
)
666 return (sig
< SIGRTMIN
) && sigismember(&signals
->signal
, sig
);
669 static int send_signal(int sig
, struct siginfo
*info
, struct task_struct
*t
,
670 struct sigpending
*signals
)
672 struct sigqueue
* q
= NULL
;
675 * Short-circuit ignored signals and support queuing
676 * exactly one non-rt signal, so that we can get more
677 * detailed information about the cause of the signal.
679 if (sig_ignored(t
, sig
) || legacy_queue(signals
, sig
))
683 * Deliver the signal to listening signalfds. This must be called
684 * with the sighand lock held.
686 signalfd_notify(t
, sig
);
689 * fast-pathed signals for kernel-internal things like SIGSTOP
692 if (info
== SEND_SIG_FORCED
)
695 /* Real-time signals must be queued if sent by sigqueue, or
696 some other real-time mechanism. It is implementation
697 defined whether kill() does so. We attempt to do so, on
698 the principle of least surprise, but since kill is not
699 allowed to fail with EAGAIN when low on memory we just
700 make sure at least one signal gets delivered and don't
701 pass on the info struct. */
703 q
= __sigqueue_alloc(t
, GFP_ATOMIC
, (sig
< SIGRTMIN
&&
704 (is_si_special(info
) ||
705 info
->si_code
>= 0)));
707 list_add_tail(&q
->list
, &signals
->list
);
708 switch ((unsigned long) info
) {
709 case (unsigned long) SEND_SIG_NOINFO
:
710 q
->info
.si_signo
= sig
;
711 q
->info
.si_errno
= 0;
712 q
->info
.si_code
= SI_USER
;
713 q
->info
.si_pid
= task_pid_vnr(current
);
714 q
->info
.si_uid
= current
->uid
;
716 case (unsigned long) SEND_SIG_PRIV
:
717 q
->info
.si_signo
= sig
;
718 q
->info
.si_errno
= 0;
719 q
->info
.si_code
= SI_KERNEL
;
724 copy_siginfo(&q
->info
, info
);
727 } else if (!is_si_special(info
)) {
728 if (sig
>= SIGRTMIN
&& info
->si_code
!= SI_USER
)
730 * Queue overflow, abort. We may abort if the signal was rt
731 * and sent by user using something other than kill().
737 sigaddset(&signals
->signal
, sig
);
741 int print_fatal_signals
;
743 static void print_fatal_signal(struct pt_regs
*regs
, int signr
)
745 printk("%s/%d: potentially unexpected fatal signal %d.\n",
746 current
->comm
, task_pid_nr(current
), signr
);
748 #if defined(__i386__) && !defined(__arch_um__)
749 printk("code at %08lx: ", regs
->ip
);
752 for (i
= 0; i
< 16; i
++) {
755 __get_user(insn
, (unsigned char *)(regs
->ip
+ i
));
756 printk("%02x ", insn
);
764 static int __init
setup_print_fatal_signals(char *str
)
766 get_option (&str
, &print_fatal_signals
);
771 __setup("print-fatal-signals=", setup_print_fatal_signals
);
774 specific_send_sig_info(int sig
, struct siginfo
*info
, struct task_struct
*t
)
778 BUG_ON(!irqs_disabled());
779 assert_spin_locked(&t
->sighand
->siglock
);
781 ret
= send_signal(sig
, info
, t
, &t
->pending
);
785 if (!sigismember(&t
->blocked
, sig
))
786 signal_wake_up(t
, sig
== SIGKILL
);
791 * Force a signal that the process can't ignore: if necessary
792 * we unblock the signal and change any SIG_IGN to SIG_DFL.
794 * Note: If we unblock the signal, we always reset it to SIG_DFL,
795 * since we do not want to have a signal handler that was blocked
796 * be invoked when user space had explicitly blocked it.
798 * We don't want to have recursive SIGSEGV's etc, for example.
801 force_sig_info(int sig
, struct siginfo
*info
, struct task_struct
*t
)
803 unsigned long int flags
;
804 int ret
, blocked
, ignored
;
805 struct k_sigaction
*action
;
807 spin_lock_irqsave(&t
->sighand
->siglock
, flags
);
808 action
= &t
->sighand
->action
[sig
-1];
809 ignored
= action
->sa
.sa_handler
== SIG_IGN
;
810 blocked
= sigismember(&t
->blocked
, sig
);
811 if (blocked
|| ignored
) {
812 action
->sa
.sa_handler
= SIG_DFL
;
814 sigdelset(&t
->blocked
, sig
);
815 recalc_sigpending_and_wake(t
);
818 ret
= specific_send_sig_info(sig
, info
, t
);
819 spin_unlock_irqrestore(&t
->sighand
->siglock
, flags
);
825 force_sig_specific(int sig
, struct task_struct
*t
)
827 force_sig_info(sig
, SEND_SIG_FORCED
, t
);
831 * Test if P wants to take SIG. After we've checked all threads with this,
832 * it's equivalent to finding no threads not blocking SIG. Any threads not
833 * blocking SIG were ruled out because they are not running and already
834 * have pending signals. Such threads will dequeue from the shared queue
835 * as soon as they're available, so putting the signal on the shared queue
836 * will be equivalent to sending it to one such thread.
838 static inline int wants_signal(int sig
, struct task_struct
*p
)
840 if (sigismember(&p
->blocked
, sig
))
842 if (p
->flags
& PF_EXITING
)
846 if (task_is_stopped_or_traced(p
))
848 return task_curr(p
) || !signal_pending(p
);
852 __group_complete_signal(int sig
, struct task_struct
*p
)
854 struct task_struct
*t
;
857 * Now find a thread we can wake up to take the signal off the queue.
859 * If the main thread wants the signal, it gets first crack.
860 * Probably the least surprising to the average bear.
862 if (wants_signal(sig
, p
))
864 else if (thread_group_empty(p
))
866 * There is just one thread and it does not need to be woken.
867 * It will dequeue unblocked signals before it runs again.
872 * Otherwise try to find a suitable thread.
874 t
= p
->signal
->curr_target
;
876 /* restart balancing at this thread */
877 t
= p
->signal
->curr_target
= p
;
879 while (!wants_signal(sig
, t
)) {
881 if (t
== p
->signal
->curr_target
)
883 * No thread needs to be woken.
884 * Any eligible threads will see
885 * the signal in the queue soon.
889 p
->signal
->curr_target
= t
;
893 * Found a killable thread. If the signal will be fatal,
894 * then start taking the whole group down immediately.
896 if (sig_fatal(p
, sig
) && !(p
->signal
->flags
& SIGNAL_GROUP_EXIT
) &&
897 !sigismember(&t
->real_blocked
, sig
) &&
898 (sig
== SIGKILL
|| !(t
->ptrace
& PT_PTRACED
))) {
900 * This signal will be fatal to the whole group.
902 if (!sig_kernel_coredump(sig
)) {
904 * Start a group exit and wake everybody up.
905 * This way we don't have other threads
906 * running and doing things after a slower
907 * thread has the fatal signal pending.
909 p
->signal
->flags
= SIGNAL_GROUP_EXIT
;
910 p
->signal
->group_exit_code
= sig
;
911 p
->signal
->group_stop_count
= 0;
914 sigaddset(&t
->pending
.signal
, SIGKILL
);
915 signal_wake_up(t
, 1);
916 } while_each_thread(p
, t
);
922 * The signal is already in the shared-pending queue.
923 * Tell the chosen thread to wake up and dequeue it.
925 signal_wake_up(t
, sig
== SIGKILL
);
930 __group_send_sig_info(int sig
, struct siginfo
*info
, struct task_struct
*p
)
934 assert_spin_locked(&p
->sighand
->siglock
);
935 handle_stop_signal(sig
, p
);
938 * Put this signal on the shared-pending queue, or fail with EAGAIN.
939 * We always use the shared queue for process-wide signals,
940 * to avoid several races.
942 ret
= send_signal(sig
, info
, p
, &p
->signal
->shared_pending
);
946 __group_complete_signal(sig
, p
);
951 * Nuke all other threads in the group.
953 void zap_other_threads(struct task_struct
*p
)
955 struct task_struct
*t
;
957 p
->signal
->group_stop_count
= 0;
959 for (t
= next_thread(p
); t
!= p
; t
= next_thread(t
)) {
961 * Don't bother with already dead threads
966 /* SIGKILL will be handled before any pending SIGSTOP */
967 sigaddset(&t
->pending
.signal
, SIGKILL
);
968 signal_wake_up(t
, 1);
972 int __fatal_signal_pending(struct task_struct
*tsk
)
974 return sigismember(&tsk
->pending
.signal
, SIGKILL
);
976 EXPORT_SYMBOL(__fatal_signal_pending
);
978 struct sighand_struct
*lock_task_sighand(struct task_struct
*tsk
, unsigned long *flags
)
980 struct sighand_struct
*sighand
;
984 sighand
= rcu_dereference(tsk
->sighand
);
985 if (unlikely(sighand
== NULL
))
988 spin_lock_irqsave(&sighand
->siglock
, *flags
);
989 if (likely(sighand
== tsk
->sighand
))
991 spin_unlock_irqrestore(&sighand
->siglock
, *flags
);
998 int group_send_sig_info(int sig
, struct siginfo
*info
, struct task_struct
*p
)
1000 unsigned long flags
;
1003 ret
= check_kill_permission(sig
, info
, p
);
1007 if (lock_task_sighand(p
, &flags
)) {
1008 ret
= __group_send_sig_info(sig
, info
, p
);
1009 unlock_task_sighand(p
, &flags
);
1017 * __kill_pgrp_info() sends a signal to a process group: this is what the tty
1018 * control characters do (^C, ^Z etc)
1021 int __kill_pgrp_info(int sig
, struct siginfo
*info
, struct pid
*pgrp
)
1023 struct task_struct
*p
= NULL
;
1024 int retval
, success
;
1028 do_each_pid_task(pgrp
, PIDTYPE_PGID
, p
) {
1029 int err
= group_send_sig_info(sig
, info
, p
);
1032 } while_each_pid_task(pgrp
, PIDTYPE_PGID
, p
);
1033 return success
? 0 : retval
;
1036 int kill_pid_info(int sig
, struct siginfo
*info
, struct pid
*pid
)
1039 struct task_struct
*p
;
1043 p
= pid_task(pid
, PIDTYPE_PID
);
1045 error
= group_send_sig_info(sig
, info
, p
);
1046 if (unlikely(error
== -ESRCH
))
1048 * The task was unhashed in between, try again.
1049 * If it is dead, pid_task() will return NULL,
1050 * if we race with de_thread() it will find the
1061 kill_proc_info(int sig
, struct siginfo
*info
, pid_t pid
)
1065 error
= kill_pid_info(sig
, info
, find_vpid(pid
));
1070 /* like kill_pid_info(), but doesn't use uid/euid of "current" */
1071 int kill_pid_info_as_uid(int sig
, struct siginfo
*info
, struct pid
*pid
,
1072 uid_t uid
, uid_t euid
, u32 secid
)
1075 struct task_struct
*p
;
1077 if (!valid_signal(sig
))
1080 read_lock(&tasklist_lock
);
1081 p
= pid_task(pid
, PIDTYPE_PID
);
1086 if ((info
== SEND_SIG_NOINFO
|| (!is_si_special(info
) && SI_FROMUSER(info
)))
1087 && (euid
!= p
->suid
) && (euid
!= p
->uid
)
1088 && (uid
!= p
->suid
) && (uid
!= p
->uid
)) {
1092 ret
= security_task_kill(p
, info
, sig
, secid
);
1095 if (sig
&& p
->sighand
) {
1096 unsigned long flags
;
1097 spin_lock_irqsave(&p
->sighand
->siglock
, flags
);
1098 ret
= __group_send_sig_info(sig
, info
, p
);
1099 spin_unlock_irqrestore(&p
->sighand
->siglock
, flags
);
1102 read_unlock(&tasklist_lock
);
1105 EXPORT_SYMBOL_GPL(kill_pid_info_as_uid
);
1108 * kill_something_info() interprets pid in interesting ways just like kill(2).
1110 * POSIX specifies that kill(-1,sig) is unspecified, but what we have
1111 * is probably wrong. Should make it like BSD or SYSV.
1114 static int kill_something_info(int sig
, struct siginfo
*info
, int pid
)
1120 ret
= kill_pid_info(sig
, info
, find_vpid(pid
));
1125 read_lock(&tasklist_lock
);
1127 ret
= __kill_pgrp_info(sig
, info
,
1128 pid
? find_vpid(-pid
) : task_pgrp(current
));
1130 int retval
= 0, count
= 0;
1131 struct task_struct
* p
;
1133 for_each_process(p
) {
1134 if (p
->pid
> 1 && !same_thread_group(p
, current
)) {
1135 int err
= group_send_sig_info(sig
, info
, p
);
1141 ret
= count
? retval
: -ESRCH
;
1143 read_unlock(&tasklist_lock
);
1149 * These are for backward compatibility with the rest of the kernel source.
1153 * These two are the most common entry points. They send a signal
1154 * just to the specific thread.
1157 send_sig_info(int sig
, struct siginfo
*info
, struct task_struct
*p
)
1160 unsigned long flags
;
1163 * Make sure legacy kernel users don't send in bad values
1164 * (normal paths check this in check_kill_permission).
1166 if (!valid_signal(sig
))
1170 * We need the tasklist lock even for the specific
1171 * thread case (when we don't need to follow the group
1172 * lists) in order to avoid races with "p->sighand"
1173 * going away or changing from under us.
1175 read_lock(&tasklist_lock
);
1176 spin_lock_irqsave(&p
->sighand
->siglock
, flags
);
1177 ret
= specific_send_sig_info(sig
, info
, p
);
1178 spin_unlock_irqrestore(&p
->sighand
->siglock
, flags
);
1179 read_unlock(&tasklist_lock
);
1183 #define __si_special(priv) \
1184 ((priv) ? SEND_SIG_PRIV : SEND_SIG_NOINFO)
1187 send_sig(int sig
, struct task_struct
*p
, int priv
)
1189 return send_sig_info(sig
, __si_special(priv
), p
);
1193 force_sig(int sig
, struct task_struct
*p
)
1195 force_sig_info(sig
, SEND_SIG_PRIV
, p
);
1199 * When things go south during signal handling, we
1200 * will force a SIGSEGV. And if the signal that caused
1201 * the problem was already a SIGSEGV, we'll want to
1202 * make sure we don't even try to deliver the signal..
1205 force_sigsegv(int sig
, struct task_struct
*p
)
1207 if (sig
== SIGSEGV
) {
1208 unsigned long flags
;
1209 spin_lock_irqsave(&p
->sighand
->siglock
, flags
);
1210 p
->sighand
->action
[sig
- 1].sa
.sa_handler
= SIG_DFL
;
1211 spin_unlock_irqrestore(&p
->sighand
->siglock
, flags
);
1213 force_sig(SIGSEGV
, p
);
1217 int kill_pgrp(struct pid
*pid
, int sig
, int priv
)
1221 read_lock(&tasklist_lock
);
1222 ret
= __kill_pgrp_info(sig
, __si_special(priv
), pid
);
1223 read_unlock(&tasklist_lock
);
1227 EXPORT_SYMBOL(kill_pgrp
);
1229 int kill_pid(struct pid
*pid
, int sig
, int priv
)
1231 return kill_pid_info(sig
, __si_special(priv
), pid
);
1233 EXPORT_SYMBOL(kill_pid
);
1236 kill_proc(pid_t pid
, int sig
, int priv
)
1241 ret
= kill_pid_info(sig
, __si_special(priv
), find_pid(pid
));
1247 * These functions support sending signals using preallocated sigqueue
1248 * structures. This is needed "because realtime applications cannot
1249 * afford to lose notifications of asynchronous events, like timer
1250 * expirations or I/O completions". In the case of Posix Timers
1251 * we allocate the sigqueue structure from the timer_create. If this
1252 * allocation fails we are able to report the failure to the application
1253 * with an EAGAIN error.
1256 struct sigqueue
*sigqueue_alloc(void)
1260 if ((q
= __sigqueue_alloc(current
, GFP_KERNEL
, 0)))
1261 q
->flags
|= SIGQUEUE_PREALLOC
;
1265 void sigqueue_free(struct sigqueue
*q
)
1267 unsigned long flags
;
1268 spinlock_t
*lock
= ¤t
->sighand
->siglock
;
1270 BUG_ON(!(q
->flags
& SIGQUEUE_PREALLOC
));
1272 * If the signal is still pending remove it from the
1273 * pending queue. We must hold ->siglock while testing
1274 * q->list to serialize with collect_signal().
1276 spin_lock_irqsave(lock
, flags
);
1277 if (!list_empty(&q
->list
))
1278 list_del_init(&q
->list
);
1279 spin_unlock_irqrestore(lock
, flags
);
1281 q
->flags
&= ~SIGQUEUE_PREALLOC
;
1285 static int do_send_sigqueue(int sig
, struct sigqueue
*q
, struct task_struct
*t
,
1286 struct sigpending
*pending
)
1288 if (unlikely(!list_empty(&q
->list
))) {
1290 * If an SI_TIMER entry is already queue just increment
1291 * the overrun count.
1294 BUG_ON(q
->info
.si_code
!= SI_TIMER
);
1295 q
->info
.si_overrun
++;
1299 if (sig_ignored(t
, sig
))
1302 signalfd_notify(t
, sig
);
1303 list_add_tail(&q
->list
, &pending
->list
);
1304 sigaddset(&pending
->signal
, sig
);
1308 int send_sigqueue(int sig
, struct sigqueue
*q
, struct task_struct
*p
)
1310 unsigned long flags
;
1313 BUG_ON(!(q
->flags
& SIGQUEUE_PREALLOC
));
1316 * The rcu based delayed sighand destroy makes it possible to
1317 * run this without tasklist lock held. The task struct itself
1318 * cannot go away as create_timer did get_task_struct().
1320 * We return -1, when the task is marked exiting, so
1321 * posix_timer_event can redirect it to the group leader
1325 if (!likely(lock_task_sighand(p
, &flags
)))
1328 ret
= do_send_sigqueue(sig
, q
, p
, &p
->pending
);
1330 if (!sigismember(&p
->blocked
, sig
))
1331 signal_wake_up(p
, sig
== SIGKILL
);
1333 unlock_task_sighand(p
, &flags
);
1341 send_group_sigqueue(int sig
, struct sigqueue
*q
, struct task_struct
*p
)
1343 unsigned long flags
;
1346 BUG_ON(!(q
->flags
& SIGQUEUE_PREALLOC
));
1348 read_lock(&tasklist_lock
);
1349 /* Since it_lock is held, p->sighand cannot be NULL. */
1350 spin_lock_irqsave(&p
->sighand
->siglock
, flags
);
1351 handle_stop_signal(sig
, p
);
1353 ret
= do_send_sigqueue(sig
, q
, p
, &p
->signal
->shared_pending
);
1355 __group_complete_signal(sig
, p
);
1357 spin_unlock_irqrestore(&p
->sighand
->siglock
, flags
);
1358 read_unlock(&tasklist_lock
);
1363 * Wake up any threads in the parent blocked in wait* syscalls.
1365 static inline void __wake_up_parent(struct task_struct
*p
,
1366 struct task_struct
*parent
)
1368 wake_up_interruptible_sync(&parent
->signal
->wait_chldexit
);
1372 * Let a parent know about the death of a child.
1373 * For a stopped/continued status change, use do_notify_parent_cldstop instead.
1376 void do_notify_parent(struct task_struct
*tsk
, int sig
)
1378 struct siginfo info
;
1379 unsigned long flags
;
1380 struct sighand_struct
*psig
;
1384 /* do_notify_parent_cldstop should have been called instead. */
1385 BUG_ON(task_is_stopped_or_traced(tsk
));
1387 BUG_ON(!tsk
->ptrace
&&
1388 (tsk
->group_leader
!= tsk
|| !thread_group_empty(tsk
)));
1390 info
.si_signo
= sig
;
1393 * we are under tasklist_lock here so our parent is tied to
1394 * us and cannot exit and release its namespace.
1396 * the only it can is to switch its nsproxy with sys_unshare,
1397 * bu uncharing pid namespaces is not allowed, so we'll always
1398 * see relevant namespace
1400 * write_lock() currently calls preempt_disable() which is the
1401 * same as rcu_read_lock(), but according to Oleg, this is not
1402 * correct to rely on this
1405 info
.si_pid
= task_pid_nr_ns(tsk
, tsk
->parent
->nsproxy
->pid_ns
);
1408 info
.si_uid
= tsk
->uid
;
1410 /* FIXME: find out whether or not this is supposed to be c*time. */
1411 info
.si_utime
= cputime_to_jiffies(cputime_add(tsk
->utime
,
1412 tsk
->signal
->utime
));
1413 info
.si_stime
= cputime_to_jiffies(cputime_add(tsk
->stime
,
1414 tsk
->signal
->stime
));
1416 info
.si_status
= tsk
->exit_code
& 0x7f;
1417 if (tsk
->exit_code
& 0x80)
1418 info
.si_code
= CLD_DUMPED
;
1419 else if (tsk
->exit_code
& 0x7f)
1420 info
.si_code
= CLD_KILLED
;
1422 info
.si_code
= CLD_EXITED
;
1423 info
.si_status
= tsk
->exit_code
>> 8;
1426 psig
= tsk
->parent
->sighand
;
1427 spin_lock_irqsave(&psig
->siglock
, flags
);
1428 if (!tsk
->ptrace
&& sig
== SIGCHLD
&&
1429 (psig
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
||
1430 (psig
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDWAIT
))) {
1432 * We are exiting and our parent doesn't care. POSIX.1
1433 * defines special semantics for setting SIGCHLD to SIG_IGN
1434 * or setting the SA_NOCLDWAIT flag: we should be reaped
1435 * automatically and not left for our parent's wait4 call.
1436 * Rather than having the parent do it as a magic kind of
1437 * signal handler, we just set this to tell do_exit that we
1438 * can be cleaned up without becoming a zombie. Note that
1439 * we still call __wake_up_parent in this case, because a
1440 * blocked sys_wait4 might now return -ECHILD.
1442 * Whether we send SIGCHLD or not for SA_NOCLDWAIT
1443 * is implementation-defined: we do (if you don't want
1444 * it, just use SIG_IGN instead).
1446 tsk
->exit_signal
= -1;
1447 if (psig
->action
[SIGCHLD
-1].sa
.sa_handler
== SIG_IGN
)
1450 if (valid_signal(sig
) && sig
> 0)
1451 __group_send_sig_info(sig
, &info
, tsk
->parent
);
1452 __wake_up_parent(tsk
, tsk
->parent
);
1453 spin_unlock_irqrestore(&psig
->siglock
, flags
);
1456 static void do_notify_parent_cldstop(struct task_struct
*tsk
, int why
)
1458 struct siginfo info
;
1459 unsigned long flags
;
1460 struct task_struct
*parent
;
1461 struct sighand_struct
*sighand
;
1463 if (tsk
->ptrace
& PT_PTRACED
)
1464 parent
= tsk
->parent
;
1466 tsk
= tsk
->group_leader
;
1467 parent
= tsk
->real_parent
;
1470 info
.si_signo
= SIGCHLD
;
1473 * see comment in do_notify_parent() abot the following 3 lines
1476 info
.si_pid
= task_pid_nr_ns(tsk
, tsk
->parent
->nsproxy
->pid_ns
);
1479 info
.si_uid
= tsk
->uid
;
1481 /* FIXME: find out whether or not this is supposed to be c*time. */
1482 info
.si_utime
= cputime_to_jiffies(tsk
->utime
);
1483 info
.si_stime
= cputime_to_jiffies(tsk
->stime
);
1488 info
.si_status
= SIGCONT
;
1491 info
.si_status
= tsk
->signal
->group_exit_code
& 0x7f;
1494 info
.si_status
= tsk
->exit_code
& 0x7f;
1500 sighand
= parent
->sighand
;
1501 spin_lock_irqsave(&sighand
->siglock
, flags
);
1502 if (sighand
->action
[SIGCHLD
-1].sa
.sa_handler
!= SIG_IGN
&&
1503 !(sighand
->action
[SIGCHLD
-1].sa
.sa_flags
& SA_NOCLDSTOP
))
1504 __group_send_sig_info(SIGCHLD
, &info
, parent
);
1506 * Even if SIGCHLD is not generated, we must wake up wait4 calls.
1508 __wake_up_parent(tsk
, parent
);
1509 spin_unlock_irqrestore(&sighand
->siglock
, flags
);
1512 static inline int may_ptrace_stop(void)
1514 if (!likely(current
->ptrace
& PT_PTRACED
))
1517 * Are we in the middle of do_coredump?
1518 * If so and our tracer is also part of the coredump stopping
1519 * is a deadlock situation, and pointless because our tracer
1520 * is dead so don't allow us to stop.
1521 * If SIGKILL was already sent before the caller unlocked
1522 * ->siglock we must see ->core_waiters != 0. Otherwise it
1523 * is safe to enter schedule().
1525 if (unlikely(current
->mm
->core_waiters
) &&
1526 unlikely(current
->mm
== current
->parent
->mm
))
1533 * Return nonzero if there is a SIGKILL that should be waking us up.
1534 * Called with the siglock held.
1536 static int sigkill_pending(struct task_struct
*tsk
)
1538 return ((sigismember(&tsk
->pending
.signal
, SIGKILL
) ||
1539 sigismember(&tsk
->signal
->shared_pending
.signal
, SIGKILL
)) &&
1540 !unlikely(sigismember(&tsk
->blocked
, SIGKILL
)));
1544 * This must be called with current->sighand->siglock held.
1546 * This should be the path for all ptrace stops.
1547 * We always set current->last_siginfo while stopped here.
1548 * That makes it a way to test a stopped process for
1549 * being ptrace-stopped vs being job-control-stopped.
1551 * If we actually decide not to stop at all because the tracer
1552 * is gone, we keep current->exit_code unless clear_code.
1554 static void ptrace_stop(int exit_code
, int clear_code
, siginfo_t
*info
)
1558 if (arch_ptrace_stop_needed(exit_code
, info
)) {
1560 * The arch code has something special to do before a
1561 * ptrace stop. This is allowed to block, e.g. for faults
1562 * on user stack pages. We can't keep the siglock while
1563 * calling arch_ptrace_stop, so we must release it now.
1564 * To preserve proper semantics, we must do this before
1565 * any signal bookkeeping like checking group_stop_count.
1566 * Meanwhile, a SIGKILL could come in before we retake the
1567 * siglock. That must prevent us from sleeping in TASK_TRACED.
1568 * So after regaining the lock, we must check for SIGKILL.
1570 spin_unlock_irq(¤t
->sighand
->siglock
);
1571 arch_ptrace_stop(exit_code
, info
);
1572 spin_lock_irq(¤t
->sighand
->siglock
);
1573 killed
= sigkill_pending(current
);
1577 * If there is a group stop in progress,
1578 * we must participate in the bookkeeping.
1580 if (current
->signal
->group_stop_count
> 0)
1581 --current
->signal
->group_stop_count
;
1583 current
->last_siginfo
= info
;
1584 current
->exit_code
= exit_code
;
1586 /* Let the debugger run. */
1587 __set_current_state(TASK_TRACED
);
1588 spin_unlock_irq(¤t
->sighand
->siglock
);
1589 read_lock(&tasklist_lock
);
1590 if (!unlikely(killed
) && may_ptrace_stop()) {
1591 do_notify_parent_cldstop(current
, CLD_TRAPPED
);
1592 read_unlock(&tasklist_lock
);
1596 * By the time we got the lock, our tracer went away.
1597 * Don't drop the lock yet, another tracer may come.
1599 __set_current_state(TASK_RUNNING
);
1601 current
->exit_code
= 0;
1602 read_unlock(&tasklist_lock
);
1606 * While in TASK_TRACED, we were considered "frozen enough".
1607 * Now that we woke up, it's crucial if we're supposed to be
1608 * frozen that we freeze now before running anything substantial.
1613 * We are back. Now reacquire the siglock before touching
1614 * last_siginfo, so that we are sure to have synchronized with
1615 * any signal-sending on another CPU that wants to examine it.
1617 spin_lock_irq(¤t
->sighand
->siglock
);
1618 current
->last_siginfo
= NULL
;
1621 * Queued signals ignored us while we were stopped for tracing.
1622 * So check for any that we should take before resuming user mode.
1623 * This sets TIF_SIGPENDING, but never clears it.
1625 recalc_sigpending_tsk(current
);
1628 void ptrace_notify(int exit_code
)
1632 BUG_ON((exit_code
& (0x7f | ~0xffff)) != SIGTRAP
);
1634 memset(&info
, 0, sizeof info
);
1635 info
.si_signo
= SIGTRAP
;
1636 info
.si_code
= exit_code
;
1637 info
.si_pid
= task_pid_vnr(current
);
1638 info
.si_uid
= current
->uid
;
1640 /* Let the debugger run. */
1641 spin_lock_irq(¤t
->sighand
->siglock
);
1642 ptrace_stop(exit_code
, 1, &info
);
1643 spin_unlock_irq(¤t
->sighand
->siglock
);
1647 finish_stop(int stop_count
)
1650 * If there are no other threads in the group, or if there is
1651 * a group stop in progress and we are the last to stop,
1652 * report to the parent. When ptraced, every thread reports itself.
1654 if (stop_count
== 0 || (current
->ptrace
& PT_PTRACED
)) {
1655 read_lock(&tasklist_lock
);
1656 do_notify_parent_cldstop(current
, CLD_STOPPED
);
1657 read_unlock(&tasklist_lock
);
1662 } while (try_to_freeze());
1664 * Now we don't run again until continued.
1666 current
->exit_code
= 0;
1670 * This performs the stopping for SIGSTOP and other stop signals.
1671 * We have to stop all threads in the thread group.
1672 * Returns nonzero if we've actually stopped and released the siglock.
1673 * Returns zero if we didn't stop and still hold the siglock.
1675 static int do_signal_stop(int signr
)
1677 struct signal_struct
*sig
= current
->signal
;
1680 if (sig
->group_stop_count
> 0) {
1682 * There is a group stop in progress. We don't need to
1683 * start another one.
1685 stop_count
= --sig
->group_stop_count
;
1687 struct task_struct
*t
;
1689 if (!likely(sig
->flags
& SIGNAL_STOP_DEQUEUED
) ||
1690 unlikely(signal_group_exit(sig
)))
1693 * There is no group stop already in progress.
1694 * We must initiate one now.
1696 sig
->group_exit_code
= signr
;
1699 for (t
= next_thread(current
); t
!= current
; t
= next_thread(t
))
1701 * Setting state to TASK_STOPPED for a group
1702 * stop is always done with the siglock held,
1703 * so this check has no races.
1705 if (!(t
->flags
& PF_EXITING
) &&
1706 !task_is_stopped_or_traced(t
)) {
1708 signal_wake_up(t
, 0);
1710 sig
->group_stop_count
= stop_count
;
1713 if (stop_count
== 0)
1714 sig
->flags
= SIGNAL_STOP_STOPPED
;
1715 current
->exit_code
= sig
->group_exit_code
;
1716 __set_current_state(TASK_STOPPED
);
1718 spin_unlock_irq(¤t
->sighand
->siglock
);
1719 finish_stop(stop_count
);
1723 static int ptrace_signal(int signr
, siginfo_t
*info
,
1724 struct pt_regs
*regs
, void *cookie
)
1726 if (!(current
->ptrace
& PT_PTRACED
))
1729 ptrace_signal_deliver(regs
, cookie
);
1731 /* Let the debugger run. */
1732 ptrace_stop(signr
, 0, info
);
1734 /* We're back. Did the debugger cancel the sig? */
1735 signr
= current
->exit_code
;
1739 current
->exit_code
= 0;
1741 /* Update the siginfo structure if the signal has
1742 changed. If the debugger wanted something
1743 specific in the siginfo structure then it should
1744 have updated *info via PTRACE_SETSIGINFO. */
1745 if (signr
!= info
->si_signo
) {
1746 info
->si_signo
= signr
;
1748 info
->si_code
= SI_USER
;
1749 info
->si_pid
= task_pid_vnr(current
->parent
);
1750 info
->si_uid
= current
->parent
->uid
;
1753 /* If the (new) signal is now blocked, requeue it. */
1754 if (sigismember(¤t
->blocked
, signr
)) {
1755 specific_send_sig_info(signr
, info
, current
);
1762 int get_signal_to_deliver(siginfo_t
*info
, struct k_sigaction
*return_ka
,
1763 struct pt_regs
*regs
, void *cookie
)
1765 sigset_t
*mask
= ¤t
->blocked
;
1770 * We'll jump back here after any time we were stopped in TASK_STOPPED.
1771 * While in TASK_STOPPED, we were considered "frozen enough".
1772 * Now that we woke up, it's crucial if we're supposed to be
1773 * frozen that we freeze now before running anything substantial.
1777 spin_lock_irq(¤t
->sighand
->siglock
);
1779 if (unlikely(current
->signal
->flags
& SIGNAL_CLD_MASK
)) {
1780 int why
= (current
->signal
->flags
& SIGNAL_STOP_CONTINUED
)
1781 ? CLD_CONTINUED
: CLD_STOPPED
;
1782 current
->signal
->flags
&= ~SIGNAL_CLD_MASK
;
1783 spin_unlock_irq(¤t
->sighand
->siglock
);
1785 read_lock(&tasklist_lock
);
1786 do_notify_parent_cldstop(current
->group_leader
, why
);
1787 read_unlock(&tasklist_lock
);
1792 struct k_sigaction
*ka
;
1794 if (unlikely(current
->signal
->group_stop_count
> 0) &&
1798 signr
= dequeue_signal(current
, mask
, info
);
1801 break; /* will return 0 */
1803 if (signr
!= SIGKILL
) {
1804 signr
= ptrace_signal(signr
, info
, regs
, cookie
);
1809 ka
= ¤t
->sighand
->action
[signr
-1];
1810 if (ka
->sa
.sa_handler
== SIG_IGN
) /* Do nothing. */
1812 if (ka
->sa
.sa_handler
!= SIG_DFL
) {
1813 /* Run the handler. */
1816 if (ka
->sa
.sa_flags
& SA_ONESHOT
)
1817 ka
->sa
.sa_handler
= SIG_DFL
;
1819 break; /* will return non-zero "signr" value */
1823 * Now we are doing the default action for this signal.
1825 if (sig_kernel_ignore(signr
)) /* Default is nothing. */
1829 * Global init gets no signals it doesn't want.
1831 if (is_global_init(current
))
1834 if (sig_kernel_stop(signr
)) {
1836 * The default action is to stop all threads in
1837 * the thread group. The job control signals
1838 * do nothing in an orphaned pgrp, but SIGSTOP
1839 * always works. Note that siglock needs to be
1840 * dropped during the call to is_orphaned_pgrp()
1841 * because of lock ordering with tasklist_lock.
1842 * This allows an intervening SIGCONT to be posted.
1843 * We need to check for that and bail out if necessary.
1845 if (signr
!= SIGSTOP
) {
1846 spin_unlock_irq(¤t
->sighand
->siglock
);
1848 /* signals can be posted during this window */
1850 if (is_current_pgrp_orphaned())
1853 spin_lock_irq(¤t
->sighand
->siglock
);
1856 if (likely(do_signal_stop(signr
))) {
1857 /* It released the siglock. */
1862 * We didn't actually stop, due to a race
1863 * with SIGCONT or something like that.
1868 spin_unlock_irq(¤t
->sighand
->siglock
);
1871 * Anything else is fatal, maybe with a core dump.
1873 current
->flags
|= PF_SIGNALED
;
1874 if ((signr
!= SIGKILL
) && print_fatal_signals
)
1875 print_fatal_signal(regs
, signr
);
1876 if (sig_kernel_coredump(signr
)) {
1878 * If it was able to dump core, this kills all
1879 * other threads in the group and synchronizes with
1880 * their demise. If we lost the race with another
1881 * thread getting here, it set group_exit_code
1882 * first and our do_group_exit call below will use
1883 * that value and ignore the one we pass it.
1885 do_coredump((long)signr
, signr
, regs
);
1889 * Death signals, no core dump.
1891 do_group_exit(signr
);
1894 spin_unlock_irq(¤t
->sighand
->siglock
);
1898 void exit_signals(struct task_struct
*tsk
)
1901 struct task_struct
*t
;
1903 if (thread_group_empty(tsk
) || signal_group_exit(tsk
->signal
)) {
1904 tsk
->flags
|= PF_EXITING
;
1908 spin_lock_irq(&tsk
->sighand
->siglock
);
1910 * From now this task is not visible for group-wide signals,
1911 * see wants_signal(), do_signal_stop().
1913 tsk
->flags
|= PF_EXITING
;
1914 if (!signal_pending(tsk
))
1917 /* It could be that __group_complete_signal() choose us to
1918 * notify about group-wide signal. Another thread should be
1919 * woken now to take the signal since we will not.
1921 for (t
= tsk
; (t
= next_thread(t
)) != tsk
; )
1922 if (!signal_pending(t
) && !(t
->flags
& PF_EXITING
))
1923 recalc_sigpending_and_wake(t
);
1925 if (unlikely(tsk
->signal
->group_stop_count
) &&
1926 !--tsk
->signal
->group_stop_count
) {
1927 tsk
->signal
->flags
= SIGNAL_STOP_STOPPED
;
1931 spin_unlock_irq(&tsk
->sighand
->siglock
);
1933 if (unlikely(group_stop
)) {
1934 read_lock(&tasklist_lock
);
1935 do_notify_parent_cldstop(tsk
, CLD_STOPPED
);
1936 read_unlock(&tasklist_lock
);
1940 EXPORT_SYMBOL(recalc_sigpending
);
1941 EXPORT_SYMBOL_GPL(dequeue_signal
);
1942 EXPORT_SYMBOL(flush_signals
);
1943 EXPORT_SYMBOL(force_sig
);
1944 EXPORT_SYMBOL(kill_proc
);
1945 EXPORT_SYMBOL(ptrace_notify
);
1946 EXPORT_SYMBOL(send_sig
);
1947 EXPORT_SYMBOL(send_sig_info
);
1948 EXPORT_SYMBOL(sigprocmask
);
1949 EXPORT_SYMBOL(block_all_signals
);
1950 EXPORT_SYMBOL(unblock_all_signals
);
1954 * System call entry points.
1957 asmlinkage
long sys_restart_syscall(void)
1959 struct restart_block
*restart
= ¤t_thread_info()->restart_block
;
1960 return restart
->fn(restart
);
1963 long do_no_restart_syscall(struct restart_block
*param
)
1969 * We don't need to get the kernel lock - this is all local to this
1970 * particular thread.. (and that's good, because this is _heavily_
1971 * used by various programs)
1975 * This is also useful for kernel threads that want to temporarily
1976 * (or permanently) block certain signals.
1978 * NOTE! Unlike the user-mode sys_sigprocmask(), the kernel
1979 * interface happily blocks "unblockable" signals like SIGKILL
1982 int sigprocmask(int how
, sigset_t
*set
, sigset_t
*oldset
)
1986 spin_lock_irq(¤t
->sighand
->siglock
);
1988 *oldset
= current
->blocked
;
1993 sigorsets(¤t
->blocked
, ¤t
->blocked
, set
);
1996 signandsets(¤t
->blocked
, ¤t
->blocked
, set
);
1999 current
->blocked
= *set
;
2004 recalc_sigpending();
2005 spin_unlock_irq(¤t
->sighand
->siglock
);
2011 sys_rt_sigprocmask(int how
, sigset_t __user
*set
, sigset_t __user
*oset
, size_t sigsetsize
)
2013 int error
= -EINVAL
;
2014 sigset_t old_set
, new_set
;
2016 /* XXX: Don't preclude handling different sized sigset_t's. */
2017 if (sigsetsize
!= sizeof(sigset_t
))
2022 if (copy_from_user(&new_set
, set
, sizeof(*set
)))
2024 sigdelsetmask(&new_set
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
2026 error
= sigprocmask(how
, &new_set
, &old_set
);
2032 spin_lock_irq(¤t
->sighand
->siglock
);
2033 old_set
= current
->blocked
;
2034 spin_unlock_irq(¤t
->sighand
->siglock
);
2038 if (copy_to_user(oset
, &old_set
, sizeof(*oset
)))
2046 long do_sigpending(void __user
*set
, unsigned long sigsetsize
)
2048 long error
= -EINVAL
;
2051 if (sigsetsize
> sizeof(sigset_t
))
2054 spin_lock_irq(¤t
->sighand
->siglock
);
2055 sigorsets(&pending
, ¤t
->pending
.signal
,
2056 ¤t
->signal
->shared_pending
.signal
);
2057 spin_unlock_irq(¤t
->sighand
->siglock
);
2059 /* Outside the lock because only this thread touches it. */
2060 sigandsets(&pending
, ¤t
->blocked
, &pending
);
2063 if (!copy_to_user(set
, &pending
, sigsetsize
))
2071 sys_rt_sigpending(sigset_t __user
*set
, size_t sigsetsize
)
2073 return do_sigpending(set
, sigsetsize
);
2076 #ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER
2078 int copy_siginfo_to_user(siginfo_t __user
*to
, siginfo_t
*from
)
2082 if (!access_ok (VERIFY_WRITE
, to
, sizeof(siginfo_t
)))
2084 if (from
->si_code
< 0)
2085 return __copy_to_user(to
, from
, sizeof(siginfo_t
))
2088 * If you change siginfo_t structure, please be sure
2089 * this code is fixed accordingly.
2090 * Please remember to update the signalfd_copyinfo() function
2091 * inside fs/signalfd.c too, in case siginfo_t changes.
2092 * It should never copy any pad contained in the structure
2093 * to avoid security leaks, but must copy the generic
2094 * 3 ints plus the relevant union member.
2096 err
= __put_user(from
->si_signo
, &to
->si_signo
);
2097 err
|= __put_user(from
->si_errno
, &to
->si_errno
);
2098 err
|= __put_user((short)from
->si_code
, &to
->si_code
);
2099 switch (from
->si_code
& __SI_MASK
) {
2101 err
|= __put_user(from
->si_pid
, &to
->si_pid
);
2102 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
2105 err
|= __put_user(from
->si_tid
, &to
->si_tid
);
2106 err
|= __put_user(from
->si_overrun
, &to
->si_overrun
);
2107 err
|= __put_user(from
->si_ptr
, &to
->si_ptr
);
2110 err
|= __put_user(from
->si_band
, &to
->si_band
);
2111 err
|= __put_user(from
->si_fd
, &to
->si_fd
);
2114 err
|= __put_user(from
->si_addr
, &to
->si_addr
);
2115 #ifdef __ARCH_SI_TRAPNO
2116 err
|= __put_user(from
->si_trapno
, &to
->si_trapno
);
2120 err
|= __put_user(from
->si_pid
, &to
->si_pid
);
2121 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
2122 err
|= __put_user(from
->si_status
, &to
->si_status
);
2123 err
|= __put_user(from
->si_utime
, &to
->si_utime
);
2124 err
|= __put_user(from
->si_stime
, &to
->si_stime
);
2126 case __SI_RT
: /* This is not generated by the kernel as of now. */
2127 case __SI_MESGQ
: /* But this is */
2128 err
|= __put_user(from
->si_pid
, &to
->si_pid
);
2129 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
2130 err
|= __put_user(from
->si_ptr
, &to
->si_ptr
);
2132 default: /* this is just in case for now ... */
2133 err
|= __put_user(from
->si_pid
, &to
->si_pid
);
2134 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
2143 sys_rt_sigtimedwait(const sigset_t __user
*uthese
,
2144 siginfo_t __user
*uinfo
,
2145 const struct timespec __user
*uts
,
2154 /* XXX: Don't preclude handling different sized sigset_t's. */
2155 if (sigsetsize
!= sizeof(sigset_t
))
2158 if (copy_from_user(&these
, uthese
, sizeof(these
)))
2162 * Invert the set of allowed signals to get those we
2165 sigdelsetmask(&these
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
2169 if (copy_from_user(&ts
, uts
, sizeof(ts
)))
2171 if (ts
.tv_nsec
>= 1000000000L || ts
.tv_nsec
< 0
2176 spin_lock_irq(¤t
->sighand
->siglock
);
2177 sig
= dequeue_signal(current
, &these
, &info
);
2179 timeout
= MAX_SCHEDULE_TIMEOUT
;
2181 timeout
= (timespec_to_jiffies(&ts
)
2182 + (ts
.tv_sec
|| ts
.tv_nsec
));
2185 /* None ready -- temporarily unblock those we're
2186 * interested while we are sleeping in so that we'll
2187 * be awakened when they arrive. */
2188 current
->real_blocked
= current
->blocked
;
2189 sigandsets(¤t
->blocked
, ¤t
->blocked
, &these
);
2190 recalc_sigpending();
2191 spin_unlock_irq(¤t
->sighand
->siglock
);
2193 timeout
= schedule_timeout_interruptible(timeout
);
2195 spin_lock_irq(¤t
->sighand
->siglock
);
2196 sig
= dequeue_signal(current
, &these
, &info
);
2197 current
->blocked
= current
->real_blocked
;
2198 siginitset(¤t
->real_blocked
, 0);
2199 recalc_sigpending();
2202 spin_unlock_irq(¤t
->sighand
->siglock
);
2207 if (copy_siginfo_to_user(uinfo
, &info
))
2220 sys_kill(int pid
, int sig
)
2222 struct siginfo info
;
2224 info
.si_signo
= sig
;
2226 info
.si_code
= SI_USER
;
2227 info
.si_pid
= task_tgid_vnr(current
);
2228 info
.si_uid
= current
->uid
;
2230 return kill_something_info(sig
, &info
, pid
);
2233 static int do_tkill(int tgid
, int pid
, int sig
)
2236 struct siginfo info
;
2237 struct task_struct
*p
;
2240 info
.si_signo
= sig
;
2242 info
.si_code
= SI_TKILL
;
2243 info
.si_pid
= task_tgid_vnr(current
);
2244 info
.si_uid
= current
->uid
;
2246 read_lock(&tasklist_lock
);
2247 p
= find_task_by_vpid(pid
);
2248 if (p
&& (tgid
<= 0 || task_tgid_vnr(p
) == tgid
)) {
2249 error
= check_kill_permission(sig
, &info
, p
);
2251 * The null signal is a permissions and process existence
2252 * probe. No signal is actually delivered.
2254 if (!error
&& sig
&& p
->sighand
) {
2255 spin_lock_irq(&p
->sighand
->siglock
);
2256 handle_stop_signal(sig
, p
);
2257 error
= specific_send_sig_info(sig
, &info
, p
);
2258 spin_unlock_irq(&p
->sighand
->siglock
);
2261 read_unlock(&tasklist_lock
);
2267 * sys_tgkill - send signal to one specific thread
2268 * @tgid: the thread group ID of the thread
2269 * @pid: the PID of the thread
2270 * @sig: signal to be sent
2272 * This syscall also checks the @tgid and returns -ESRCH even if the PID
2273 * exists but it's not belonging to the target process anymore. This
2274 * method solves the problem of threads exiting and PIDs getting reused.
2276 asmlinkage
long sys_tgkill(int tgid
, int pid
, int sig
)
2278 /* This is only valid for single tasks */
2279 if (pid
<= 0 || tgid
<= 0)
2282 return do_tkill(tgid
, pid
, sig
);
2286 * Send a signal to only one task, even if it's a CLONE_THREAD task.
2289 sys_tkill(int pid
, int sig
)
2291 /* This is only valid for single tasks */
2295 return do_tkill(0, pid
, sig
);
2299 sys_rt_sigqueueinfo(int pid
, int sig
, siginfo_t __user
*uinfo
)
2303 if (copy_from_user(&info
, uinfo
, sizeof(siginfo_t
)))
2306 /* Not even root can pretend to send signals from the kernel.
2307 Nor can they impersonate a kill(), which adds source info. */
2308 if (info
.si_code
>= 0)
2310 info
.si_signo
= sig
;
2312 /* POSIX.1b doesn't mention process groups. */
2313 return kill_proc_info(sig
, &info
, pid
);
2316 int do_sigaction(int sig
, struct k_sigaction
*act
, struct k_sigaction
*oact
)
2318 struct task_struct
*t
= current
;
2319 struct k_sigaction
*k
;
2322 if (!valid_signal(sig
) || sig
< 1 || (act
&& sig_kernel_only(sig
)))
2325 k
= &t
->sighand
->action
[sig
-1];
2327 spin_lock_irq(¤t
->sighand
->siglock
);
2332 sigdelsetmask(&act
->sa
.sa_mask
,
2333 sigmask(SIGKILL
) | sigmask(SIGSTOP
));
2337 * "Setting a signal action to SIG_IGN for a signal that is
2338 * pending shall cause the pending signal to be discarded,
2339 * whether or not it is blocked."
2341 * "Setting a signal action to SIG_DFL for a signal that is
2342 * pending and whose default action is to ignore the signal
2343 * (for example, SIGCHLD), shall cause the pending signal to
2344 * be discarded, whether or not it is blocked"
2346 if (__sig_ignored(t
, sig
)) {
2348 sigaddset(&mask
, sig
);
2349 rm_from_queue_full(&mask
, &t
->signal
->shared_pending
);
2351 rm_from_queue_full(&mask
, &t
->pending
);
2353 } while (t
!= current
);
2357 spin_unlock_irq(¤t
->sighand
->siglock
);
2362 do_sigaltstack (const stack_t __user
*uss
, stack_t __user
*uoss
, unsigned long sp
)
2368 oss
.ss_sp
= (void __user
*) current
->sas_ss_sp
;
2369 oss
.ss_size
= current
->sas_ss_size
;
2370 oss
.ss_flags
= sas_ss_flags(sp
);
2379 if (!access_ok(VERIFY_READ
, uss
, sizeof(*uss
))
2380 || __get_user(ss_sp
, &uss
->ss_sp
)
2381 || __get_user(ss_flags
, &uss
->ss_flags
)
2382 || __get_user(ss_size
, &uss
->ss_size
))
2386 if (on_sig_stack(sp
))
2392 * Note - this code used to test ss_flags incorrectly
2393 * old code may have been written using ss_flags==0
2394 * to mean ss_flags==SS_ONSTACK (as this was the only
2395 * way that worked) - this fix preserves that older
2398 if (ss_flags
!= SS_DISABLE
&& ss_flags
!= SS_ONSTACK
&& ss_flags
!= 0)
2401 if (ss_flags
== SS_DISABLE
) {
2406 if (ss_size
< MINSIGSTKSZ
)
2410 current
->sas_ss_sp
= (unsigned long) ss_sp
;
2411 current
->sas_ss_size
= ss_size
;
2416 if (copy_to_user(uoss
, &oss
, sizeof(oss
)))
2425 #ifdef __ARCH_WANT_SYS_SIGPENDING
2428 sys_sigpending(old_sigset_t __user
*set
)
2430 return do_sigpending(set
, sizeof(*set
));
2435 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
2436 /* Some platforms have their own version with special arguments others
2437 support only sys_rt_sigprocmask. */
2440 sys_sigprocmask(int how
, old_sigset_t __user
*set
, old_sigset_t __user
*oset
)
2443 old_sigset_t old_set
, new_set
;
2447 if (copy_from_user(&new_set
, set
, sizeof(*set
)))
2449 new_set
&= ~(sigmask(SIGKILL
) | sigmask(SIGSTOP
));
2451 spin_lock_irq(¤t
->sighand
->siglock
);
2452 old_set
= current
->blocked
.sig
[0];
2460 sigaddsetmask(¤t
->blocked
, new_set
);
2463 sigdelsetmask(¤t
->blocked
, new_set
);
2466 current
->blocked
.sig
[0] = new_set
;
2470 recalc_sigpending();
2471 spin_unlock_irq(¤t
->sighand
->siglock
);
2477 old_set
= current
->blocked
.sig
[0];
2480 if (copy_to_user(oset
, &old_set
, sizeof(*oset
)))
2487 #endif /* __ARCH_WANT_SYS_SIGPROCMASK */
2489 #ifdef __ARCH_WANT_SYS_RT_SIGACTION
2491 sys_rt_sigaction(int sig
,
2492 const struct sigaction __user
*act
,
2493 struct sigaction __user
*oact
,
2496 struct k_sigaction new_sa
, old_sa
;
2499 /* XXX: Don't preclude handling different sized sigset_t's. */
2500 if (sigsetsize
!= sizeof(sigset_t
))
2504 if (copy_from_user(&new_sa
.sa
, act
, sizeof(new_sa
.sa
)))
2508 ret
= do_sigaction(sig
, act
? &new_sa
: NULL
, oact
? &old_sa
: NULL
);
2511 if (copy_to_user(oact
, &old_sa
.sa
, sizeof(old_sa
.sa
)))
2517 #endif /* __ARCH_WANT_SYS_RT_SIGACTION */
2519 #ifdef __ARCH_WANT_SYS_SGETMASK
2522 * For backwards compatibility. Functionality superseded by sigprocmask.
2528 return current
->blocked
.sig
[0];
2532 sys_ssetmask(int newmask
)
2536 spin_lock_irq(¤t
->sighand
->siglock
);
2537 old
= current
->blocked
.sig
[0];
2539 siginitset(¤t
->blocked
, newmask
& ~(sigmask(SIGKILL
)|
2541 recalc_sigpending();
2542 spin_unlock_irq(¤t
->sighand
->siglock
);
2546 #endif /* __ARCH_WANT_SGETMASK */
2548 #ifdef __ARCH_WANT_SYS_SIGNAL
2550 * For backwards compatibility. Functionality superseded by sigaction.
2552 asmlinkage
unsigned long
2553 sys_signal(int sig
, __sighandler_t handler
)
2555 struct k_sigaction new_sa
, old_sa
;
2558 new_sa
.sa
.sa_handler
= handler
;
2559 new_sa
.sa
.sa_flags
= SA_ONESHOT
| SA_NOMASK
;
2560 sigemptyset(&new_sa
.sa
.sa_mask
);
2562 ret
= do_sigaction(sig
, &new_sa
, &old_sa
);
2564 return ret
? ret
: (unsigned long)old_sa
.sa
.sa_handler
;
2566 #endif /* __ARCH_WANT_SYS_SIGNAL */
2568 #ifdef __ARCH_WANT_SYS_PAUSE
2573 current
->state
= TASK_INTERRUPTIBLE
;
2575 return -ERESTARTNOHAND
;
2580 #ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND
2581 asmlinkage
long sys_rt_sigsuspend(sigset_t __user
*unewset
, size_t sigsetsize
)
2585 /* XXX: Don't preclude handling different sized sigset_t's. */
2586 if (sigsetsize
!= sizeof(sigset_t
))
2589 if (copy_from_user(&newset
, unewset
, sizeof(newset
)))
2591 sigdelsetmask(&newset
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
2593 spin_lock_irq(¤t
->sighand
->siglock
);
2594 current
->saved_sigmask
= current
->blocked
;
2595 current
->blocked
= newset
;
2596 recalc_sigpending();
2597 spin_unlock_irq(¤t
->sighand
->siglock
);
2599 current
->state
= TASK_INTERRUPTIBLE
;
2601 set_thread_flag(TIF_RESTORE_SIGMASK
);
2602 return -ERESTARTNOHAND
;
2604 #endif /* __ARCH_WANT_SYS_RT_SIGSUSPEND */
2606 __attribute__((weak
)) const char *arch_vma_name(struct vm_area_struct
*vma
)
2611 void __init
signals_init(void)
2613 sigqueue_cachep
= KMEM_CACHE(sigqueue
, SLAB_PANIC
);