From patchwork Thu Aug 18 07:13:42 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 9286911 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 D6F2B60574 for ; Thu, 18 Aug 2016 07:13:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C48E128F49 for ; Thu, 18 Aug 2016 07:13:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B93EC29039; Thu, 18 Aug 2016 07:13:55 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 41CF228F49 for ; Thu, 18 Aug 2016 07:13:55 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 574876E9B2; Thu, 18 Aug 2016 07:13:53 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lb2-smtp-cloud3.xs4all.net (lb2-smtp-cloud3.xs4all.net [194.109.24.26]) by gabe.freedesktop.org (Postfix) with ESMTPS id E2A426E9B2 for ; Thu, 18 Aug 2016 07:13:51 +0000 (UTC) Received: from tschai.lan ([90.149.38.145]) by smtp-cloud3.xs4all.net with ESMTP id YXDi1t00Q37uBN201XDmeL; Thu, 18 Aug 2016 09:13:50 +0200 Received: from [127.0.0.1] (localhost [127.0.0.1]) by tschai.lan (Postfix) with ESMTPSA id A71A3180164; Thu, 18 Aug 2016 09:13:42 +0200 (CEST) From: Hans Verkuil Subject: [PATCH for v4.8] cec-edid: check for IEEE identifier To: Linux Media Mailing List Message-ID: <09104964-b93a-cbdb-8065-13558aa85f74@xs4all.nl> Date: Thu, 18 Aug 2016 09:13:42 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 Cc: Mailing list - DRI developers X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The cec_get_edid_spa_location() function did not verify that the IEEE identifier in the Vendor Specific Data Block matched the HDMI-LLC identifier. This could result in the wrong VSDB block being returned. For example, for HDMI 2.0 EDIDs there is also a HDMI Forum VSDB. So check the IEEE identifier as well. Signed-off-by: Hans Verkuil diff --git a/drivers/media/cec-edid.c b/drivers/media/cec-edid.c index 7001824..5719b99 100644 --- a/drivers/media/cec-edid.c +++ b/drivers/media/cec-edid.c @@ -70,7 +70,10 @@ static unsigned int cec_get_edid_spa_location(const u8 *edid, unsigned int size) u8 tag = edid[i] >> 5; u8 len = edid[i] & 0x1f; - if (tag == 3 && len >= 5 && i + len <= end) + if (tag == 3 && len >= 5 && i + len <= end && + edid[i + 1] == 0x03 && + edid[i + 2] == 0x0c && + edid[i + 3] == 0x00) return i + 4; i += len + 1; } while (i < end);