Commit f8738c5c authored Jun 27, 2007 by Davide Libenzi Committed by Linus Torvalds Jun 28, 2007

avoid spurious POLLIN returns in signalfd



The new code in kernel/signal.c does not allow fetching private signals
from another task.  This patch avoid spurious POLLIN returns from a
signalfd poll(2) operation.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 58e78475

fs/signalfd.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -133,7 +133,8 @@ static unsigned int signalfd_poll(struct file file, poll_table wait)
		* the peer disconnects.
		*/
		if (signalfd_lock(ctx, &lk)) {
		if (next_signal(&lk.tsk->pending, &ctx->sigmask) > 0 \|\|
		if ((lk.tsk == current &&
		next_signal(&lk.tsk->pending, &ctx->sigmask) > 0) \|\|
		next_signal(&lk.tsk->signal->shared_pending,
		&ctx->sigmask) > 0)
		events \|= POLLIN;