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).

Benjamin Herrenschmidt committed 19 years ago

Commit caec4e81 parent bd197231 file · +7 −1Browse files

Showing the changes to kernel (1 of 1 file). Show all

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kernel/signal.c+7−1

@@ -363,7 +363,13 @@ static int __dequeue_signal(struct sigpending pending, sigset_t mask, · 362 unmodified lines
363	363	*/
364	364	int dequeue_signal(struct task_struct tsk, sigset_t mask, siginfo_t *info)
365	365	{
366		− int signr = __dequeue_signal(&tsk->pending, mask, info);
	366	+ int signr = 0;
	367	+
	368	+ /* We only dequeue private signals from ourselves, we don't let
	369	+ * signalfd steal them
	370	+ */
	371	+ if (tsk == current)
	372	+ signr = __dequeue_signal(&tsk->pending, mask, info);
367	373	if (!signr) {
368	374	signr = __dequeue_signal(&tsk->signal->shared_pending,
369	375	mask, info);