From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7994EC67871 for ; Sat, 6 Oct 2018 18:01:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D3AA21473 for ; Sat, 6 Oct 2018 18:01:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3D3AA21473 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=canonical.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728009AbeJGBGA (ORCPT ); Sat, 6 Oct 2018 21:06:00 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:59979 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725740AbeJGBF7 (ORCPT ); Sat, 6 Oct 2018 21:05:59 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1g8qtb-0001cq-FA; Sat, 06 Oct 2018 18:01:43 +0000 From: Colin King To: Mauro Carvalho Chehab , linux-media@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] media: cx231xx: fix potential sign-extension overflow on large shift Date: Sat, 6 Oct 2018 19:01:42 +0100 Message-Id: <20181006180142.28443-1-colin.king@canonical.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Colin Ian King Shifting the u8 value[3] by an int can lead to sign-extension overflow. For example, if value[3] is 0xff and the shift is 24 then it is promoted to int and then the top bit is sign-extended so that all upper 32 bits are set. Fix this by casting value[3] to a u32 before the shift. Detected by CoverityScan, CID#1016522 ("Unintended sign extension") Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Signed-off-by: Colin Ian King --- drivers/media/usb/cx231xx/cx231xx-video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/usb/cx231xx/cx231xx-video.c b/drivers/media/usb/cx231xx/cx231xx-video.c index 29160df76cf7..f2f034c5cd62 100644 --- a/drivers/media/usb/cx231xx/cx231xx-video.c +++ b/drivers/media/usb/cx231xx/cx231xx-video.c @@ -1389,7 +1389,7 @@ int cx231xx_g_register(struct file *file, void *priv, ret = cx231xx_read_ctrl_reg(dev, VRT_GET_REGISTER, (u16)reg->reg, value, 4); reg->val = value[0] | value[1] << 8 | - value[2] << 16 | value[3] << 24; + value[2] << 16 | (u32)value[3] << 24; reg->size = 4; break; case 1: /* AFE - read byte */ -- 2.17.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Colin King Date: Sat, 06 Oct 2018 18:01:42 +0000 Subject: [PATCH] media: cx231xx: fix potential sign-extension overflow on large shift Message-Id: <20181006180142.28443-1-colin.king@canonical.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Mauro Carvalho Chehab , linux-media@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org From: Colin Ian King Shifting the u8 value[3] by an int can lead to sign-extension overflow. For example, if value[3] is 0xff and the shift is 24 then it is promoted to int and then the top bit is sign-extended so that all upper 32 bits are set. Fix this by casting value[3] to a u32 before the shift. Detected by CoverityScan, CID#1016522 ("Unintended sign extension") Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Signed-off-by: Colin Ian King --- drivers/media/usb/cx231xx/cx231xx-video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/usb/cx231xx/cx231xx-video.c b/drivers/media/usb/cx231xx/cx231xx-video.c index 29160df76cf7..f2f034c5cd62 100644 --- a/drivers/media/usb/cx231xx/cx231xx-video.c +++ b/drivers/media/usb/cx231xx/cx231xx-video.c @@ -1389,7 +1389,7 @@ int cx231xx_g_register(struct file *file, void *priv, ret = cx231xx_read_ctrl_reg(dev, VRT_GET_REGISTER, (u16)reg->reg, value, 4); reg->val = value[0] | value[1] << 8 | - value[2] << 16 | value[3] << 24; + value[2] << 16 | (u32)value[3] << 24; reg->size = 4; break; case 1: /* AFE - read byte */ -- 2.17.1