From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753667Ab2GWBpd (ORCPT ); Sun, 22 Jul 2012 21:45:33 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54526 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753560Ab2GWBnx (ORCPT ); Sun, 22 Jul 2012 21:43:53 -0400 Message-Id: <20120723010655.027064805@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 23 Jul 2012 02:07:14 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jason Baron , "Yurij M. Plotnikov" , Nelson Elhage , Davide Libenzi , "Alexandra N. Kossovsky" Subject: [ 023/108] epoll: clear the tfile_check_list on -ELOOP In-Reply-To: <20120723010651.408577075@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jason Baron commit 13d518074a952d33d47c428419693f63389547e9 upstream. An epoll_ctl(,EPOLL_CTL_ADD,,) operation can return '-ELOOP' to prevent circular epoll dependencies from being created. However, in that case we do not properly clear the 'tfile_check_list'. Thus, add a call to clear_tfile_check_list() for the -ELOOP case. Signed-off-by: Jason Baron Reported-by: Yurij M. Plotnikov Cc: Nelson Elhage Cc: Davide Libenzi Tested-by: Alexandra N. Kossovsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- fs/eventpoll.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 739b098..c0b3c70 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1663,8 +1663,10 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd, if (op == EPOLL_CTL_ADD) { if (is_file_epoll(tfile)) { error = -ELOOP; - if (ep_loop_check(ep, tfile) != 0) + if (ep_loop_check(ep, tfile) != 0) { + clear_tfile_check_list(); goto error_tgt_fput; + } } else list_add(&tfile->f_tfile_llink, &tfile_check_list); }