From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20120124023933.282045084@clark.kroah.org> Date: Mon, 23 Jan 2012 18:35:25 -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: [105/129] [SCSI] sym53c8xx: Fix NULL pointer dereference in slave_destroy In-Reply-To: <20120124024041.GA18422@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ Content-Length: 946 Lines: 30 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 @@ -839,6 +839,10 @@ 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) {