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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D30F4C43334 for ; Mon, 13 Jun 2022 11:50:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356150AbiFMLt6 (ORCPT ); Mon, 13 Jun 2022 07:49:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356738AbiFMLt3 (ORCPT ); Mon, 13 Jun 2022 07:49:29 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F3834D27D; Mon, 13 Jun 2022 03:53:17 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E125E61257; Mon, 13 Jun 2022 10:53:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04136C34114; Mon, 13 Jun 2022 10:53:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655117596; bh=+7WXVu5kP53VqQA0ADTMHnERl1ovLtqDxs2TO4AWIFs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TK12bFLO8/tkMZbx/d7FijM1zEkPee/R5721vy8ag6v0ZXVS0UXaEkVVc1ygfpL9B cEBpcEEdFsZYGFiKlUqMWH7WN4T5i6Q4HfpT4+PcDLNusaEQnsfNZu3fhmyw5YYmaG wFi8fF4gAKFwzumUy7hX2BlNH8wFUuE2Twfb6/6Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Jani Nikula , Sasha Levin Subject: [PATCH 4.19 059/287] drm/edid: fix invalid EDID extension block filtering Date: Mon, 13 Jun 2022 12:08:03 +0200 Message-Id: <20220613094925.659106949@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094923.832156175@linuxfoundation.org> References: <20220613094923.832156175@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jani Nikula [ Upstream commit 3aefc722ff52076407203b6af9713de567993adf ] The invalid EDID block filtering uses the number of valid EDID extensions instead of all EDID extensions for looping the extensions in the copy. This is fine, by coincidence, if all the invalid blocks are at the end of the EDID. However, it's completely broken if there are invalid extensions in the middle; the invalid blocks are included and valid blocks are excluded. Fix it by modifying the base block after, not before, the copy. Fixes: 14544d0937bf ("drm/edid: Only print the bad edid when aborting") Reported-by: Ville Syrjälä Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220330170426.349248-1-jani.nikula@intel.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_edid.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index ef26095719c5..28ea3d260bea 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1709,9 +1709,6 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, connector_bad_edid(connector, edid, edid[0x7e] + 1); - edid[EDID_LENGTH-1] += edid[0x7e] - valid_extensions; - edid[0x7e] = valid_extensions; - new = kmalloc_array(valid_extensions + 1, EDID_LENGTH, GFP_KERNEL); if (!new) @@ -1728,6 +1725,9 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, base += EDID_LENGTH; } + new[EDID_LENGTH - 1] += new[0x7e] - valid_extensions; + new[0x7e] = valid_extensions; + kfree(edid); edid = new; } -- 2.35.1