Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755529Ab3JUJTu (ORCPT ); Mon, 21 Oct 2013 05:19:50 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39529 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753705Ab3JUIv3 (ORCPT ); Mon, 21 Oct 2013 04:51:29 -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, "Dmitry Vyukov" , "James Bottomley" , "Alan Stern" Date: Mon, 21 Oct 2013 09:46:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 063/149] [SCSI] sd: Fix potential out-of-bounds access In-Reply-To: X-SA-Exim-Connect-IP: 212.20.242.100 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 Content-Length: 1602 Lines: 48 3.2.52-rc1 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: Ben Hutchings --- drivers/scsi/sd.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2136,14 +2136,9 @@ sd_read_cache_type(struct scsi_disk *sdk } } - 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); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/