Commit d0305882 authored Mar 31, 2009 by Tony Battersby Committed by Linus Torvalds Apr 01, 2009

epoll: remember the event if epoll_wait returns -EFAULT



If epoll_wait returns -EFAULT, the event that was being returned when the
fault was encountered will be forgotten.  This is not a big deal since
EFAULT will happen only if a buggy userspace program passes in a bad
address, in which case what happens later usually doesn't matter.
However, it is easy to remember the event for later, and this patch makes
a simple change to do that.

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent abff55ce

fs/eventpoll.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -1054,8 +1054,10 @@ static int ep_send_events_proc(struct eventpoll ep, struct list_head head,
		*/
		if (revents) {
		if (__put_user(revents, &uevent->events) \|\|
		__put_user(epi->event.data, &uevent->data))
		__put_user(epi->event.data, &uevent->data)) {
		list_add(&epi->rdllink, head);
		return eventcnt ? eventcnt : -EFAULT;
		}
		eventcnt++;
		uevent++;
		if (epi->event.events & EPOLLONESHOT)

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