From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756016AbZG1XHr (ORCPT ); Tue, 28 Jul 2009 19:07:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755911AbZG1XEB (ORCPT ); Tue, 28 Jul 2009 19:04:01 -0400 Received: from kroah.org ([198.145.64.141]:42979 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755590AbZG1XD6 (ORCPT ); Tue, 28 Jul 2009 19:03:58 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Tue Jul 28 15:59:43 2009 Message-Id: <20090728225943.431729356@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Tue, 28 Jul 2009 15:58:45 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, NeilBrown Subject: [patch 17/37] md: avoid dereferencing NULL pointer when accessing suspend_* sysfs attributes. References: <20090728225828.431071451@mini.kroah.org> Content-Disposition: inline; filename=md-avoid-dereferencing-null-pointer-when-accessing-suspend_-sysfs-attributes.patch In-Reply-To: <20090728230145.GA10486@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: NeilBrown commit b8d966efd9a46a9a35beac50cbff6e30565125ef upstream. If we try to modify one of the md/ sysfs files suspend_lo or suspend_hi when the array is not active, we dereference a NULL. Protect against that. Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- drivers/md/md.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3281,7 +3281,8 @@ suspend_lo_store(mddev_t *mddev, const c char *e; unsigned long long new = simple_strtoull(buf, &e, 10); - if (mddev->pers->quiesce == NULL) + if (mddev->pers == NULL || + mddev->pers->quiesce == NULL) return -EINVAL; if (buf == e || (*e && *e != '\n')) return -EINVAL; @@ -3309,7 +3310,8 @@ suspend_hi_store(mddev_t *mddev, const c char *e; unsigned long long new = simple_strtoull(buf, &e, 10); - if (mddev->pers->quiesce == NULL) + if (mddev->pers == NULL || + mddev->pers->quiesce == NULL) return -EINVAL; if (buf == e || (*e && *e != '\n')) return -EINVAL;