diff options
authorOleg Nesterov <oleg@tv-sign.ru>2008-05-26 20:55:42 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-05-26 10:37:06 -0700
commitc8e85b4f4b9ee23bf0e79bdeb3da274a0f9c663f (patch)
parent84a881657d391121cd88c37f0a312dec3528fa44 (diff)
posix timers: sigqueue_free: don't free sigqueue if it is queued
Currently sigqueue_free() removes sigqueue from list, but doesn't cancel the pending signal. This is not consistent, the task should either receive the "full" signal along with siginfo_t, or it shouldn't receive the signal at all. Change sigqueue_free() to clear SIGQUEUE_PREALLOC but leave sigqueue on list if it is queued. This is a user-visible change. If the signal is blocked, it stays queued after sys_timer_delete() until unblocked with the "stale" si_code/si_value, and of course it is still counted wrt RLIMIT_SIGPENDING which also limits the number of posix timers. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Austin Clements <amdragon+kernelbugzilla@mit.edu> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 10 insertions, 6 deletions
diff --git a/kernel/signal.c b/kernel/signal.c
index 12ffea7c201d..2955f6c4f36e 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1240,18 +1240,22 @@ void sigqueue_free(struct sigqueue *q)
- * 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() or with
+ * 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)