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 CD036C38A2D for ; Mon, 24 Oct 2022 11:31:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229817AbiJXLbp (ORCPT ); Mon, 24 Oct 2022 07:31:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229535AbiJXLbm (ORCPT ); Mon, 24 Oct 2022 07:31:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 67B4F54C92; Mon, 24 Oct 2022 04:31:41 -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 04B246124A; Mon, 24 Oct 2022 11:31:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1F06BC433D6; Mon, 24 Oct 2022 11:31:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666611100; bh=qmEFW0fJBE9f21+UkGHuAk8h4xaJA2B7CXNSIEtfcvo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k/hluu41OjvGP+FqpSy3ekcPoikY+LW046p0xffxpFkaMVRC44sR46OVQKRyqAFdn F6sSC4Z9EMKDhzzCpQF5WMoY+MwvHAbtPG2ZM9prJZlHl4CbMdNQ/dsrBXicgllDCv epwvi0kCOeNCH85xskKouw42e8Ptb+wb8m03FbaE= 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 Subject: [PATCH 6.0 01/20] drm/i915/bios: Validate fp_timing terminator presence Date: Mon, 24 Oct 2022 13:31:03 +0200 Message-Id: <20221024112934.482437706@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112934.415391158@linuxfoundation.org> References: <20221024112934.415391158@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ville Syrjälä commit 4e78d6023c15c6acce8fbe42e13027c460395522 upstream. Validate the LFP data block a bit hardwer by making sure the fp_timing terminators (0xffff) are where we expect them to be. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220818192223.29881-2-ville.syrjala@linux.intel.com Reviewed-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/display/intel_bios.c | 60 ++++++++++++++++-------------- 1 file changed, 32 insertions(+), 28 deletions(-) --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -135,18 +135,6 @@ static u32 raw_block_offset(const void * return block - bdb; } -/* size of the block excluding the header */ -static u32 raw_block_size(const void *bdb, enum bdb_block_id section_id) -{ - const void *block; - - block = find_raw_section(bdb, section_id); - if (!block) - return 0; - - return get_blocksize(block); -} - struct bdb_block_entry { struct list_head node; enum bdb_block_id section_id; @@ -231,9 +219,14 @@ static bool validate_lfp_data_ptrs(const { int fp_timing_size, dvo_timing_size, panel_pnp_id_size, panel_name_size; int data_block_size, lfp_data_size; + const void *data_block; int i; - data_block_size = raw_block_size(bdb, BDB_LVDS_LFP_DATA); + data_block = find_raw_section(bdb, BDB_LVDS_LFP_DATA); + if (!data_block) + return false; + + data_block_size = get_blocksize(data_block); if (data_block_size == 0) return false; @@ -261,21 +254,6 @@ static bool validate_lfp_data_ptrs(const if (16 * lfp_data_size > data_block_size) return false; - /* - * Except for vlv/chv machines all real VBTs seem to have 6 - * unaccounted bytes in the fp_timing table. And it doesn't - * appear to be a really intentional hole as the fp_timing - * 0xffff terminator is always within those 6 missing bytes. - */ - if (fp_timing_size + dvo_timing_size + panel_pnp_id_size != lfp_data_size && - fp_timing_size + 6 + dvo_timing_size + panel_pnp_id_size != lfp_data_size) - return false; - - if (ptrs->ptr[0].fp_timing.offset + fp_timing_size > ptrs->ptr[0].dvo_timing.offset || - ptrs->ptr[0].dvo_timing.offset + dvo_timing_size != ptrs->ptr[0].panel_pnp_id.offset || - ptrs->ptr[0].panel_pnp_id.offset + panel_pnp_id_size != lfp_data_size) - return false; - /* make sure the table entries have uniform size */ for (i = 1; i < 16; i++) { if (ptrs->ptr[i].fp_timing.table_size != fp_timing_size || @@ -289,6 +267,23 @@ static bool validate_lfp_data_ptrs(const return false; } + /* + * Except for vlv/chv machines all real VBTs seem to have 6 + * unaccounted bytes in the fp_timing table. And it doesn't + * appear to be a really intentional hole as the fp_timing + * 0xffff terminator is always within those 6 missing bytes. + */ + if (fp_timing_size + 6 + dvo_timing_size + panel_pnp_id_size == lfp_data_size) + fp_timing_size += 6; + + if (fp_timing_size + dvo_timing_size + panel_pnp_id_size != lfp_data_size) + return false; + + if (ptrs->ptr[0].fp_timing.offset + fp_timing_size != ptrs->ptr[0].dvo_timing.offset || + ptrs->ptr[0].dvo_timing.offset + dvo_timing_size != ptrs->ptr[0].panel_pnp_id.offset || + ptrs->ptr[0].panel_pnp_id.offset + panel_pnp_id_size != lfp_data_size) + return false; + /* make sure the tables fit inside the data block */ for (i = 0; i < 16; i++) { if (ptrs->ptr[i].fp_timing.offset + fp_timing_size > data_block_size || @@ -300,6 +295,15 @@ static bool validate_lfp_data_ptrs(const if (ptrs->panel_name.offset + 16 * panel_name_size > data_block_size) return false; + /* make sure fp_timing terminators are present at expected locations */ + for (i = 0; i < 16; i++) { + const u16 *t = data_block + ptrs->ptr[i].fp_timing.offset + + fp_timing_size - 2; + + if (*t != 0xffff) + return false; + } + return true; }