From patchwork Mon Apr 23 17:40:54 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: 10357915 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 6FCF160225 for ; Mon, 23 Apr 2018 18:03:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5E2D128BF6 for ; Mon, 23 Apr 2018 18:03:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 462A528BF9; Mon, 23 Apr 2018 18:03:40 +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=unavailable 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 AC77328BF6 for ; Mon, 23 Apr 2018 18:03:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932312AbeDWSDi (ORCPT ); Mon, 23 Apr 2018 14:03:38 -0400 Received: from gateway20.websitewelcome.com ([192.185.62.46]:30622 "EHLO gateway20.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932109AbeDWSDh (ORCPT ); Mon, 23 Apr 2018 14:03:37 -0400 X-Greylist: delayed 1359 seconds by postgrey-1.27 at vger.kernel.org; Mon, 23 Apr 2018 14:03:37 EDT Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway20.websitewelcome.com (Postfix) with ESMTP id 0E188400DDFEF for ; Mon, 23 Apr 2018 12:40:58 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id AfSUfUgFvA3CSAfSUfalFK; Mon, 23 Apr 2018 12:40:58 -0500 X-Authority-Reason: nr=8 Received: from [189.145.48.65] (port=49558 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.89_1) (envelope-from ) id 1fAfST-004Nvv-Hx; Mon, 23 Apr 2018 12:40:57 -0500 Date: Mon, 23 Apr 2018 12:40:54 -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: Jonathan Corbet Subject: [PATCH 04/11] marvell-ccic: mcam-core: fix potential Spectre variant 1 Message-ID: <64785db2204b1a4446d012e4508c16c523c43345.1524499368.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: 1fAfST-004Nvv-Hx X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.145.48.65]:49558 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 36 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP fmt->index can be controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. Smatch warning: drivers/media/platform/marvell-ccic/mcam-core.c:1323 mcam_vidioc_enum_fmt_vid_cap() warn: potential spectre issue 'mcam_formats' Fix this by sanitizing fmt->index before using it to index mcam_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/marvell-ccic/mcam-core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/media/platform/marvell-ccic/mcam-core.c b/drivers/media/platform/marvell-ccic/mcam-core.c index 80670ee..0a54dba 100644 --- a/drivers/media/platform/marvell-ccic/mcam-core.c +++ b/drivers/media/platform/marvell-ccic/mcam-core.c @@ -33,6 +33,8 @@ #include "mcam-core.h" +#include + #ifdef MCAM_MODE_VMALLOC /* * Internal DMA buffer management. Since the controller cannot do S/G I/O, @@ -1318,6 +1320,7 @@ static int mcam_vidioc_enum_fmt_vid_cap(struct file *filp, { if (fmt->index >= N_MCAM_FMTS) return -EINVAL; + fmt->index = array_index_nospec(fmt->index, N_MCAM_FMTS); strlcpy(fmt->description, mcam_formats[fmt->index].desc, sizeof(fmt->description)); fmt->pixelformat = mcam_formats[fmt->index].pixelformat;