From patchwork Sat Apr 11 12:09:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 228000 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 704D3C2BBFD for ; Sat, 11 Apr 2020 12:27:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C54F20644 for ; Sat, 11 Apr 2020 12:27:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586608036; bh=kn6do4sZUl1m9RB0bbgLrYd5xmWGiUYapZhBmgCfQGI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HmBzMofS06D9t4niid2RywAuTsVO7/XcP2E1KSdDpZgZNX5NcPfyYjeHN/0VcyNoO /UvBUvATrpaPoIvygjYiA+rQCZrhkF3DPIcBABTebRdzJ6MdurfLiNG5PWLMAsTbF2 wG8hbGFSIuTGQnGagDtQjJU8Y65X0uYO/7L0Fj1w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726876AbgDKMOh (ORCPT ); Sat, 11 Apr 2020 08:14:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:48032 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727954AbgDKMOf (ORCPT ); Sat, 11 Apr 2020 08:14:35 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D0CFA20644; Sat, 11 Apr 2020 12:14:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586607274; bh=kn6do4sZUl1m9RB0bbgLrYd5xmWGiUYapZhBmgCfQGI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zJ5wc2JU/pTcE+e68J98YUvmmSsHE8me/atNWo8s2SMVV7Z9NJdVeWTRz1La7naWt qziuHGykIjRbNl5JKVMrNPIefMS7EWPU8Py1YUJcwTpkODNB3w0THM5xjxUy+hQRgQ pvEc2dm77yFczr1FMuqdFPInOSwU+/W6cV9Hbd+4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hans Verkuil , Lyude Paul , Alex Deucher , Lee Jones Subject: [PATCH 4.14 38/38] drm_dp_mst_topology: fix broken drm_dp_sideband_parse_remote_dpcd_read() Date: Sat, 11 Apr 2020 14:09:22 +0200 Message-Id: <20200411115441.432558800@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200411115437.795556138@linuxfoundation.org> References: <20200411115437.795556138@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hans Verkuil commit a4c30a4861c54af78c4eb8b7855524c1a96d9f80 upstream. When parsing the reply of a DP_REMOTE_DPCD_READ DPCD command the result is wrong due to a missing idx increment. This was never noticed since DP_REMOTE_DPCD_READ is currently not used, but if you enable it, then it is all wrong. Signed-off-by: Hans Verkuil Reviewed-by: Lyude Paul Acked-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/e72ddac2-1dc0-100a-d816-9ac98ac009dd@xs4all.nl Signed-off-by: Lee Jones Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_dp_mst_topology.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -433,6 +433,7 @@ static bool drm_dp_sideband_parse_remote if (idx > raw->curlen) goto fail_len; repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx]; + idx++; if (idx > raw->curlen) goto fail_len;