From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755947Ab3I3KOR (ORCPT ); Mon, 30 Sep 2013 06:14:17 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43861 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755879Ab3I3KNs (ORCPT ); Mon, 30 Sep 2013 06:13:48 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Alan Stern , James Bottomley , Luis Henriques Subject: [PATCH 102/104] [SCSI] sd: Fix potential out-of-bounds access Date: Mon, 30 Sep 2013 11:11:19 +0100 Message-Id: <1380535881-9239-103-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1380535881-9239-1-git-send-email-luis.henriques@canonical.com> References: <1380535881-9239-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.22 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit 984f1733fcee3fbc78d47e26c5096921c5d9946a upstream. This patch fixes an out-of-bounds error in sd_read_cache_type(), found by Google's AddressSanitizer tool. When the loop ends, we know that "offset" lies beyond the end of the data in the buffer, so no Caching mode page was found. In theory it may be present, but the buffer size is limited to 512 bytes. Signed-off-by: Alan Stern Reported-by: Dmitry Vyukov Signed-off-by: James Bottomley Signed-off-by: Luis Henriques --- drivers/scsi/sd.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 8e18431..68eb46e 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2226,14 +2226,9 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer) } } - if (modepage == 0x3F) { - sd_printk(KERN_ERR, sdkp, "No Caching mode page " - "present\n"); - goto defaults; - } else if ((buffer[offset] & 0x3f) != modepage) { - sd_printk(KERN_ERR, sdkp, "Got wrong page\n"); - goto defaults; - } + sd_printk(KERN_ERR, sdkp, "No Caching mode page found\n"); + goto defaults; + Page_found: if (modepage == 8) { sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0); -- 1.8.3.2