Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755782Ab2F0JCc (ORCPT ); Wed, 27 Jun 2012 05:02:32 -0400 Received: from acsinet15.oracle.com ([141.146.126.227]:21333 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755731Ab2F0JCa (ORCPT ); Wed, 27 Jun 2012 05:02:30 -0400 Date: Wed, 27 Jun 2012 12:02:15 +0300 From: Dan Carpenter To: Grant Likely Cc: spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [patch -resend] spi/spidev: handle integer wrap in spidev_message() Message-ID: <20120627090215.GG31212@elgon.mountain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120627085800.GA3007@mwanda> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1131 Lines: 29 "k_tmp->len" and "total" are unsigned integers. The first message could be close to "bufsiz" (4096) and then the next message could be 4GB which would cause an integer overflow. Signed-off-by: Dan Carpenter --- I don't have a way to test this. I originally sent this message on Tue, 18 Oct 2011. I'm not totally sure what the implications are but it seemed like there might be security implications. I honestly don't know. I never received any feedback on the patch. diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c index 830adbe..aab05e1 100644 --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -241,7 +241,7 @@ static int spidev_message(struct spidev_data *spidev, k_tmp->len = u_tmp->len; total += k_tmp->len; - if (total > bufsiz) { + if (total > bufsiz || total < k_tmp->len) { status = -EMSGSIZE; goto done; } -- 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/