From caec4e8dc85e0644ec24aeb36285e1ba02da58cc Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 12 Jun 2007 08:16:18 +1000 Subject: [PATCH] Fix signalfd interaction with thread-private signals Don't let signalfd dequeue private signals off other threads (in the case of things like SIGILL or SIGSEGV, trying to do so would result in undefined behaviour on who actually gets the signal, since they are force unblocked). Signed-off-by: Benjamin Herrenschmidt Acked-by: Davide Libenzi Signed-off-by: Linus Torvalds --- kernel/signal.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/signal.c b/kernel/signal.c index fe590e00db8d..f9405609774e 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -363,7 +363,13 @@ static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, */ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) { - int signr = __dequeue_signal(&tsk->pending, mask, info); + int signr = 0; + + /* We only dequeue private signals from ourselves, we don't let + * signalfd steal them + */ + if (tsk == current) + signr = __dequeue_signal(&tsk->pending, mask, info); if (!signr) { signr = __dequeue_signal(&tsk->signal->shared_pending, mask, info);