aboutsummaryrefslogtreecommitdiff
path: root/kernel/signal.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/signal.c')
-rw-r--r--kernel/signal.c49
1 files changed, 23 insertions, 26 deletions
diff --git a/kernel/signal.c b/kernel/signal.c
index ad63109e413..79295238109 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -378,8 +378,7 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
/* We only dequeue private signals from ourselves, we don't let
* signalfd steal them
*/
- if (likely(tsk == current))
- signr = __dequeue_signal(&tsk->pending, mask, info);
+ signr = __dequeue_signal(&tsk->pending, mask, info);
if (!signr) {
signr = __dequeue_signal(&tsk->signal->shared_pending,
mask, info);
@@ -407,8 +406,7 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
}
}
}
- if (likely(tsk == current))
- recalc_sigpending();
+ recalc_sigpending();
if (signr && unlikely(sig_kernel_stop(signr))) {
/*
* Set a marker that we have dequeued a stop signal. Our
@@ -425,7 +423,7 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
if (!(tsk->signal->flags & SIGNAL_GROUP_EXIT))
tsk->signal->flags |= SIGNAL_STOP_DEQUEUED;
}
- if (signr && likely(tsk == current) &&
+ if (signr &&
((info->si_code & __SI_MASK) == __SI_TIMER) &&
info->si_sys_private){
/*
@@ -533,18 +531,18 @@ static int check_kill_permission(int sig, struct siginfo *info,
if (!valid_signal(sig))
return error;
- error = audit_signal_info(sig, t); /* Let audit system see the signal */
- if (error)
- return error;
-
- error = -EPERM;
- if ((info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info)))
- && ((sig != SIGCONT) ||
- (process_session(current) != process_session(t)))
- && (current->euid ^ t->suid) && (current->euid ^ t->uid)
- && (current->uid ^ t->suid) && (current->uid ^ t->uid)
- && !capable(CAP_KILL))
+ if (info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info))) {
+ error = audit_signal_info(sig, t); /* Let audit system see the signal */
+ if (error)
+ return error;
+ error = -EPERM;
+ if (((sig != SIGCONT) ||
+ (process_session(current) != process_session(t)))
+ && (current->euid ^ t->suid) && (current->euid ^ t->uid)
+ && (current->uid ^ t->suid) && (current->uid ^ t->uid)
+ && !capable(CAP_KILL))
return error;
+ }
return security_task_kill(t, info, sig, 0);
}
@@ -1300,20 +1298,19 @@ struct sigqueue *sigqueue_alloc(void)
void sigqueue_free(struct sigqueue *q)
{
unsigned long flags;
+ spinlock_t *lock = &current->sighand->siglock;
+
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
/*
* If the signal is still pending remove it from the
- * pending queue.
+ * pending queue. We must hold ->siglock while testing
+ * q->list to serialize with collect_signal().
*/
- if (unlikely(!list_empty(&q->list))) {
- spinlock_t *lock = &current->sighand->siglock;
- read_lock(&tasklist_lock);
- spin_lock_irqsave(lock, flags);
- if (!list_empty(&q->list))
- list_del_init(&q->list);
- spin_unlock_irqrestore(lock, flags);
- read_unlock(&tasklist_lock);
- }
+ spin_lock_irqsave(lock, flags);
+ if (!list_empty(&q->list))
+ list_del_init(&q->list);
+ spin_unlock_irqrestore(lock, flags);
+
q->flags &= ~SIGQUEUE_PREALLOC;
__sigqueue_free(q);
}