From patchwork Tue Sep 9 12:11:23 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 4869111 Return-Path: X-Original-To: patchwork-linux-media@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id ECB65C0338 for ; Tue, 9 Sep 2014 12:12:11 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2F5AC20117 for ; Tue, 9 Sep 2014 12:12:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF96820108 for ; Tue, 9 Sep 2014 12:12:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756124AbaIIMMB (ORCPT ); Tue, 9 Sep 2014 08:12:01 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:50792 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753352AbaIIMMA (ORCPT ); Tue, 9 Sep 2014 08:12:00 -0400 Received: from ucsinet21.oracle.com (ucsinet21.oracle.com [156.151.31.93]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s89CBbAV026500 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 9 Sep 2014 12:11:38 GMT Received: from userz7022.oracle.com (userz7022.oracle.com [156.151.31.86]) by ucsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s89CBauP020535 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 9 Sep 2014 12:11:37 GMT Received: from abhmp0016.oracle.com (abhmp0016.oracle.com [141.146.116.22]) by userz7022.oracle.com (8.14.5+Sun/8.14.4) with ESMTP id s89CBZxB017725; Tue, 9 Sep 2014 12:11:35 GMT Received: from mwanda (/197.157.0.15) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 09 Sep 2014 05:11:34 -0700 Date: Tue, 9 Sep 2014 15:11:23 +0300 From: Dan Carpenter To: Stefan Richter Cc: Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux1394-devel@lists.sourceforge.net, kernel-janitors@vger.kernel.org Subject: [patch v2] [media] firewire: firedtv-avc: potential buffer overflow Message-ID: <20140909121123.GC19760@mwanda> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20140908144033.42a0762d@kant> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Spam-Status: No, score=-9.4 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP "program_info_length" is user controlled and can go up to 4095. The operand[] array has 509 bytes so we need to add a limit here to prevent buffer overflows. The " - 4" in the limit check is because we have 4 bytes more data to add after the memcpy(). Signed-off-by: Dan Carpenter --- v2: The first version didn't have the - 4. Thanks for catching that Stafan. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/media/firewire/firedtv-avc.c b/drivers/media/firewire/firedtv-avc.c index d1a1a13..251a556 100644 --- a/drivers/media/firewire/firedtv-avc.c +++ b/drivers/media/firewire/firedtv-avc.c @@ -1157,6 +1157,10 @@ int avc_ca_pmt(struct firedtv *fdtv, char *msg, int length) if (pmt_cmd_id != 1 && pmt_cmd_id != 4) dev_err(fdtv->device, "invalid pmt_cmd_id %d\n", pmt_cmd_id); + if (program_info_length > sizeof(c->operand) - 4 - write_pos) { + ret = -EINVAL; + goto out; + } memcpy(&c->operand[write_pos], &msg[read_pos], program_info_length); @@ -1180,6 +1184,12 @@ int avc_ca_pmt(struct firedtv *fdtv, char *msg, int length) dev_err(fdtv->device, "invalid pmt_cmd_id %d " "at stream level\n", pmt_cmd_id); + if (es_info_length > sizeof(c->operand) - 4 - + write_pos) { + ret = -EINVAL; + goto out; + } + memcpy(&c->operand[write_pos], &msg[read_pos], es_info_length); read_pos += es_info_length;