From patchwork Mon Apr 23 17:47:20 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 10357809 X-Patchwork-Delegate: geert@linux-m68k.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0C05D601BE for ; Mon, 23 Apr 2018 17:47:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F00C128BEB for ; Mon, 23 Apr 2018 17:47:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E4AD528BEE; Mon, 23 Apr 2018 17:47:25 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6D43928BEB for ; Mon, 23 Apr 2018 17:47:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932205AbeDWRrY (ORCPT ); Mon, 23 Apr 2018 13:47:24 -0400 Received: from gateway21.websitewelcome.com ([192.185.45.154]:26024 "EHLO gateway21.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932206AbeDWRrW (ORCPT ); Mon, 23 Apr 2018 13:47:22 -0400 X-Greylist: delayed 578 seconds by postgrey-1.27 at vger.kernel.org; Mon, 23 Apr 2018 13:47:22 EDT Received: from cm17.websitewelcome.com (cm17.websitewelcome.com [100.42.49.20]) by gateway21.websitewelcome.com (Postfix) with ESMTP id 63C16400DD6C0 for ; Mon, 23 Apr 2018 12:47:21 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id AfYffbNUxy2aLAfYffxVgf; Mon, 23 Apr 2018 12:47:21 -0500 X-Authority-Reason: nr=8 Received: from [189.145.48.65] (port=49584 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.89_1) (envelope-from ) id 1fAfYe-0004i9-S3; Mon, 23 Apr 2018 12:47:21 -0500 Date: Mon, 23 Apr 2018 12:47:20 -0500 From: "Gustavo A. R. Silva" To: Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , Dan Carpenter Cc: Niklas =?iso-8859-1?Q?S=F6derlund?= , linux-renesas-soc@vger.kernel.org Subject: [PATCH 06/11] rcar-v4l2: fix potential Spectre variant 1 Message-ID: <45621d4cd0639906cf16c4b4d666e8cd0e1c3694.1524499368.git.gustavo@embeddedor.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.145.48.65 X-Source-L: No X-Exim-ID: 1fAfYe-0004i9-S3 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.145.48.65]:49584 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 49 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP f->index can be controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. Smatch warning: drivers/media/platform/rcar-vin/rcar-v4l2.c:344 rvin_enum_fmt_vid_cap() warn: potential spectre issue 'rvin_formats' Fix this by sanitizing f->index before using it to index rvin_formats. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: stable@vger.kernel.org Reported-by: Dan Carpenter Signed-off-by: Gustavo A. R. Silva --- drivers/media/platform/rcar-vin/rcar-v4l2.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/media/platform/rcar-vin/rcar-v4l2.c b/drivers/media/platform/rcar-vin/rcar-v4l2.c index b479b88..bbfc3b8 100644 --- a/drivers/media/platform/rcar-vin/rcar-v4l2.c +++ b/drivers/media/platform/rcar-vin/rcar-v4l2.c @@ -22,6 +22,8 @@ #include "rcar-vin.h" +#include + #define RVIN_DEFAULT_FORMAT V4L2_PIX_FMT_YUYV #define RVIN_MAX_WIDTH 2048 #define RVIN_MAX_HEIGHT 2048 @@ -340,7 +342,7 @@ static int rvin_enum_fmt_vid_cap(struct file *file, void *priv, { if (f->index >= ARRAY_SIZE(rvin_formats)) return -EINVAL; - + f->index = array_index_nospec(f->index, ARRAY_SIZE(rvin_formats)); f->pixelformat = rvin_formats[f->index].fourcc; return 0;