From: Tony Battersby Date: Tue, 31 Mar 2009 22:24:14 +0000 (-0700) Subject: epoll: remember the event if epoll_wait returns -EFAULT X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d0305882825784e74f68a56eee6c3a812a99f235;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git 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 Acked-by: Davide Libenzi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/eventpoll.c b/fs/eventpoll.c index db4365f8a75c..c806a0c4383c 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -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)