Merge branch 'work.epoll' of git://git.kernel.org/pub/scm/linux/kerne…

…l/git/viro/vfs

Pull epoll fixup from Al Viro:
 "Fixup for epoll regression; there's a better solution longer term, but
  this is the least intrusive fix"

* 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix regression in "epoll: Keep a reference on files added to the check list"

fs/eventpoll.c

@@ -1995,9 +1995,9 @@ static int ep_loop_check_proc(void *priv, void *cookie, int call_nests)
 			 * during ep_insert().
 			 */
 			if (list_empty(&epi->ffd.file->f_tfile_llink)) {
-				get_file(epi->ffd.file);
-				list_add(&epi->ffd.file->f_tfile_llink,
-					 &tfile_check_list);
+				if (get_file_rcu(epi->ffd.file))
+					list_add(&epi->ffd.file->f_tfile_llink,
+						 &tfile_check_list);
 			}
 		}
 	}