From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752398AbdIIWxj (ORCPT ); Sat, 9 Sep 2017 18:53:39 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41346 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751778AbdIIWYk (ORCPT ); Sat, 9 Sep 2017 18:24:40 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Ian Kent" , "NeilBrown" , "Linus Torvalds" Date: Sat, 09 Sep 2017 22:47:40 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 093/106] autofs: sanity check status reported with AUTOFS_DEV_IOCTL_FAIL In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 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 3.2.93-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit 9fa4eb8e490a28de40964b1b0e583d8db4c7e57c upstream. If a positive status is passed with the AUTOFS_DEV_IOCTL_FAIL ioctl, autofs4_d_automount() will return ERR_PTR(status) with that status to follow_automount(), which will then dereference an invalid pointer. So treat a positive status the same as zero, and map to ENOENT. See comment in systemd src/core/automount.c::automount_send_ready(). Link: http://lkml.kernel.org/r/871sqwczx5.fsf@notabene.neil.brown.name Signed-off-by: NeilBrown Cc: Ian Kent Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- fs/autofs4/dev-ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/autofs4/dev-ioctl.c +++ b/fs/autofs4/dev-ioctl.c @@ -345,7 +345,7 @@ static int autofs_dev_ioctl_fail(struct int status; token = (autofs_wqt_t) param->fail.token; - status = param->fail.status ? param->fail.status : -ENOENT; + status = param->fail.status < 0 ? param->fail.status : -ENOENT; return autofs4_wait_release(sbi, token, status); }