From patchwork Tue Nov 17 22:43:38 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 2088 Return-path: Envelope-to: mchehab@infradead.org Delivery-date: Tue, 17 Nov 2009 22:44:38 +0000 Received: from bombadil.infradead.org [18.85.46.34] by pedra.chehab.org with IMAP (fetchmail-6.3.6) for (single-drop); Tue, 17 Nov 2009 20:51:59 -0200 (BRST) Received: from vger.kernel.org ([209.132.176.167]) by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) id 1NAWms-0004sg-7B; Tue, 17 Nov 2009 22:44:38 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756537AbZKQWoY (ORCPT + 1 other); Tue, 17 Nov 2009 17:44:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756585AbZKQWoU (ORCPT ); Tue, 17 Nov 2009 17:44:20 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:37997 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756302AbZKQWoT (ORCPT ); Tue, 17 Nov 2009 17:44:19 -0500 Received: from imap1.linux-foundation.org (imap1.linux-foundation.org [140.211.169.55]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id nAHMhdvp016247 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 17 Nov 2009 14:43:40 -0800 Received: from localhost.localdomain (localhost [127.0.0.1]) by imap1.linux-foundation.org (8.13.5.20060308/8.13.5/Debian-3ubuntu1.1) with ESMTP id nAHMhc0D029228; Tue, 17 Nov 2009 14:43:38 -0800 Message-Id: <200911172243.nAHMhc0D029228@imap1.linux-foundation.org> Subject: [patch 2/5] quickcam_messenger.c: possible buffer overflow while use strncat To: mchehab@infradead.org Cc: linux-media@vger.kernel.org, akpm@linux-foundation.org, strakh@ispras.ru From: akpm@linux-foundation.org Date: Tue, 17 Nov 2009 14:43:38 -0800 MIME-Version: 1.0 X-Spam-Status: No, hits=-3.518 required=5 tests=AWL, BAYES_00, OSDL_HEADER_SUBJECT_BRACKETED X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.13 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Alexander Strakh In driver ./drivers/media/video/usbvideo/quickcam_messenger.c in line 91: 91 usb_make_path(dev, cam->input_physname, sizeof(cam->input_physname)); After this line we use strncat: 92 strncat(cam->input_physname, "/input0", sizeof(cam->input_physname)); where sizeof(cam->input_physname) returns length of cam->input_phisname without length for null-symbol. But this parameter must be - "maximum numbers of bytes to copy", i.e.: sizeof(cam->input_physname)-strlen(cam->input_physname)-1. In this case, after call to usb_make_path the similar drivers use strlcat. Like in: drivers/hid/usbhid/hid-core.c: 1152 usb_make_path(dev, hid->phys, sizeof(hid->phys)); 1153 strlcat(hid->phys, "/input", sizeof(hid->phys)); Found by Linux Driver Verification Project. Use strlcat instead of strncat. Signed-off-by: Alexander Strakh Cc: Mauro Carvalho Chehab Signed-off-by: Andrew Morton --- drivers/media/video/usbvideo/quickcam_messenger.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN drivers/media/video/usbvideo/quickcam_messenger.c~quickcam_messengerc-possible-buffer-overflow-while-use-strncat drivers/media/video/usbvideo/quickcam_messenger.c --- a/drivers/media/video/usbvideo/quickcam_messenger.c~quickcam_messengerc-possible-buffer-overflow-while-use-strncat +++ a/drivers/media/video/usbvideo/quickcam_messenger.c @@ -89,7 +89,7 @@ static void qcm_register_input(struct qc int error; usb_make_path(dev, cam->input_physname, sizeof(cam->input_physname)); - strncat(cam->input_physname, "/input0", sizeof(cam->input_physname)); + strlcat(cam->input_physname, "/input0", sizeof(cam->input_physname)); cam->input = input_dev = input_allocate_device(); if (!input_dev) {