spin_unlock_irqrestore(&t->sighand->siglock, flags);
}
+static void __flush_itimer_signals(struct sigpending *pending)
+{
+ sigset_t signal, retain;
+ struct sigqueue *q, *n;
+
+ signal = pending->signal;
+ sigemptyset(&retain);
+
+ list_for_each_entry_safe(q, n, &pending->list, list) {
+ int sig = q->info.si_signo;
+
+ if (likely(q->info.si_code != SI_TIMER)) {
+ sigaddset(&retain, sig);
+ } else {
+ sigdelset(&signal, sig);
+ list_del_init(&q->list);
+ __sigqueue_free(q);
+ }
+ }
+
+ sigorsets(&pending->signal, &signal, &retain);
+}
+
+void flush_itimer_signals(void)
+{
+ struct task_struct *tsk = current;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tsk->sighand->siglock, flags);
+ __flush_itimer_signals(&tsk->pending);
+ __flush_itimer_signals(&tsk->signal->shared_pending);
+ spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
+}
+
void ignore_signals(struct task_struct *t)
{
int i;
static int check_kill_permission(int sig, struct siginfo *info,
struct task_struct *t)
{
+ struct pid *sid;
int error;
if (!valid_signal(sig))
if (error)
return error;
- if (((sig != SIGCONT) || (task_session_nr(current) != task_session_nr(t)))
- && (current->euid ^ t->suid) && (current->euid ^ t->uid)
- && (current->uid ^ t->suid) && (current->uid ^ t->uid)
- && !capable(CAP_KILL))
- return -EPERM;
+ if ((current->euid ^ t->suid) && (current->euid ^ t->uid) &&
+ (current->uid ^ t->suid) && (current->uid ^ t->uid) &&
+ !capable(CAP_KILL)) {
+ switch (sig) {
+ case SIGCONT:
+ sid = task_session(t);
+ /*
+ * We don't return the error if sid == NULL. The
+ * task was unhashed, the caller must notice this.
+ */
+ if (!sid || sid == task_session(current))
+ break;
+ default:
+ return -EPERM;
+ }
+ }
return security_task_kill(t, info, sig, 0);
}
* Found a killable thread. If the signal will be fatal,
* then start taking the whole group down immediately.
*/
- if (sig_fatal(p, sig) && !(signal->flags & SIGNAL_GROUP_EXIT) &&
+ if (sig_fatal(p, sig) &&
+ !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) &&
!sigismember(&t->real_blocked, sig) &&
(sig == SIGKILL || !(t->ptrace & PT_PTRACED))) {
/*
* since we do not want to have a signal handler that was blocked
* be invoked when user space had explicitly blocked it.
*
- * We don't want to have recursive SIGSEGV's etc, for example.
+ * We don't want to have recursive SIGSEGV's etc, for example,
+ * that is why we also clear SIGNAL_UNKILLABLE.
*/
int
force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
recalc_sigpending_and_wake(t);
}
}
+ if (action->sa.sa_handler == SIG_DFL)
+ t->signal->flags &= ~SIGNAL_UNKILLABLE;
ret = specific_send_sig_info(sig, info, t);
spin_unlock_irqrestore(&t->sighand->siglock, flags);
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
/*
- * If the signal is still pending remove it from the
- * pending queue. We must hold ->siglock while testing
- * q->list to serialize with collect_signal().
+ * We must hold ->siglock while testing q->list
+ * to serialize with collect_signal() or with
+ * __exit_signal()->flush_sigqueue().
*/
spin_lock_irqsave(lock, flags);
+ q->flags &= ~SIGQUEUE_PREALLOC;
+ /*
+ * If it is queued it will be freed when dequeued,
+ * like the "regular" sigqueue.
+ */
if (!list_empty(&q->list))
- list_del_init(&q->list);
+ q = NULL;
spin_unlock_irqrestore(lock, flags);
- q->flags &= ~SIGQUEUE_PREALLOC;
- __sigqueue_free(q);
+ if (q)
+ __sigqueue_free(q);
}
int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group)
} else {
struct task_struct *t;
- if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) ||
+ if (unlikely((sig->flags & (SIGNAL_STOP_DEQUEUED | SIGNAL_UNKILLABLE))
+ != SIGNAL_STOP_DEQUEUED) ||
unlikely(signal_group_exit(sig)))
return 0;
/*
/*
* Global init gets no signals it doesn't want.
*/
- if (is_global_init(current))
+ if (unlikely(signal->flags & SIGNAL_UNKILLABLE) &&
+ !signal_group_exit(signal))
continue;
if (sig_kernel_stop(signr)) {
current->state = TASK_INTERRUPTIBLE;
schedule();
- set_thread_flag(TIF_RESTORE_SIGMASK);
+ set_restore_sigmask();
return -ERESTARTNOHAND;
}
#endif /* __ARCH_WANT_SYS_RT_SIGSUSPEND */