From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755246Ab2AWXq1 (ORCPT ); Mon, 23 Jan 2012 18:46:27 -0500 Received: from cantor2.suse.de ([195.135.220.15]:42077 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754830Ab2AWXqX (ORCPT ); Mon, 23 Jan 2012 18:46:23 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Mon Jan 23 15:42:03 2012 Message-Id: <20120123234203.816160826@clark.kroah.org> User-Agent: quilt/0.50-11.1 Date: Mon, 23 Jan 2012 15:41:11 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Stratos Psomadakis , James Bottomley Subject: [25/27] [SCSI] sym53c8xx: Fix NULL pointer dereference in slave_destroy In-Reply-To: <20120123234224.GA19510@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Stratos Psomadakis commit cced5041ed5a2d1352186510944b0ddfbdbe4c0b upstream. sym53c8xx_slave_destroy unconditionally assumes that sym53c8xx_slave_alloc has succesesfully allocated a sym_lcb. This can lead to a NULL pointer dereference (exposed by commit 4e6c82b). Signed-off-by: Stratos Psomadakis Signed-off-by: James Bottomley Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/sym53c8xx_2/sym_glue.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/scsi/sym53c8xx_2/sym_glue.c +++ b/drivers/scsi/sym53c8xx_2/sym_glue.c @@ -837,6 +837,10 @@ static void sym53c8xx_slave_destroy(stru struct sym_lcb *lp = sym_lp(tp, sdev->lun); unsigned long flags; + /* if slave_alloc returned before allocating a sym_lcb, return */ + if (!lp) + return; + spin_lock_irqsave(np->s.host->host_lock, flags); if (lp->busy_itlq || lp->busy_itl) {