leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

posix timers: sigqueue_free: don't free sigqueue if it is queued

Browse Source 
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>
This commit is contained in:
Oleg Nesterov 2008-05-26 20:55:42 +04:00 committed by Linus Torvalds
parent 84a881657d
commit c8e85b4f4b
1 changed files with 10 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
kernel/signal.c
View File

@ -1240,18 +1240,22 @@ void sigqueue_free(struct sigqueue *q)
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() 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)