From patchwork Mon Oct 24 12:33:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jani Nikula X-Patchwork-Id: 13017565 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F1CDEECAAA1 for ; Mon, 24 Oct 2022 12:34:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5B1B310E4E2; Mon, 24 Oct 2022 12:34:33 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4DEFB10E4D5; Mon, 24 Oct 2022 12:34:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1666614868; x=1698150868; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=jFNhNAQS7BoL2wpIwTvAJB4BZ76AYZ7eywRxep+G5Vs=; b=WP8HGKYsgxNr3JIEUZI2mYkeZlYUVHwWbhtaDRNWcsXcaRoeFGMoFOyY 3Nm9gto2PFxVp5FXbREshOd3+7BJF7i6Ta6CE/DqsM12Bz1oWs6fZumg0 M/OyL4608OwKpKJVbtR9q9EtKIa6AD43c3xhqZeE8SoC8dgPM7D79CvdY 9pebSi11cnIV7fpVU4imVEmAXr7UxkL74DIrhq+zl3VIY/FRIDDFNgRCN 4gz+zIaR9b7lLwPuoW/bcQlOR1ocDm7nqm4WnkfVgE9X5hR2ZuEJhjcqA VQf98cTGdvCLa7TFlDOYWkd+AwsPPmQi5yktKB9Ev4r6UJbxfII8Fln0a A==; X-IronPort-AV: E=McAfee;i="6500,9779,10509"; a="294803392" X-IronPort-AV: E=Sophos;i="5.95,209,1661842800"; d="scan'208";a="294803392" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2022 05:34:27 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10509"; a="633693782" X-IronPort-AV: E=Sophos;i="5.95,209,1661842800"; d="scan'208";a="633693782" Received: from emontau-mobl2.ger.corp.intel.com (HELO localhost) ([10.252.52.221]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2022 05:34:25 -0700 From: Jani Nikula To: dri-devel@lists.freedesktop.org Subject: [PATCH v2 08/16] drm/edid: add function for checking drm_edid validity Date: Mon, 24 Oct 2022 15:33:36 +0300 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jani.nikula@intel.com, intel-gfx@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" We've lacked a function for immutable validity check on drm_edid. Add one. Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä --- drivers/gpu/drm/drm_edid.c | 30 ++++++++++++++++++++++++++++++ include/drm/drm_edid.h | 1 + 2 files changed, 31 insertions(+) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 616c1cdc7507..c3cf942186b7 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2040,6 +2040,36 @@ bool drm_edid_is_valid(struct edid *edid) } EXPORT_SYMBOL(drm_edid_is_valid); +/** + * drm_edid_valid - sanity check EDID data + * @drm_edid: EDID data + * + * Sanity check an EDID. Cross check block count against allocated size and + * checksum the blocks. + * + * Return: True if the EDID data is valid, false otherwise. + */ +bool drm_edid_valid(const struct drm_edid *drm_edid) +{ + int i; + + if (!drm_edid) + return false; + + if (edid_size_by_blocks(__drm_edid_block_count(drm_edid)) != drm_edid->size) + return false; + + for (i = 0; i < drm_edid_block_count(drm_edid); i++) { + const void *block = drm_edid_block_data(drm_edid, i); + + if (!edid_block_valid(block, i == 0)) + return false; + } + + return true; +} +EXPORT_SYMBOL(drm_edid_valid); + static struct edid *edid_filter_invalid_blocks(struct edid *edid, size_t *alloc_size) { diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index 05380681a4fb..a2e25e7e6ee5 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -606,6 +606,7 @@ drm_display_mode_from_cea_vic(struct drm_device *dev, const struct drm_edid *drm_edid_alloc(const void *edid, size_t size); const struct drm_edid *drm_edid_dup(const struct drm_edid *drm_edid); void drm_edid_free(const struct drm_edid *drm_edid); +bool drm_edid_valid(const struct drm_edid *drm_edid); const struct edid *drm_edid_raw(const struct drm_edid *drm_edid); const struct drm_edid *drm_edid_read(struct drm_connector *connector); const struct drm_edid *drm_edid_read_ddc(struct drm_connector *connector,