From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9B6B1425CF5; Sat, 12 Sep 2026 10:38:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789209506; cv=none; b=OGEu2wencbkcaU6p8WowkfQM+nrlWP/jSB87dFb7x/fomtfknlaMN28c09LzIUaqws7kIttq46SGQC3xmWljoafF2qe+7FSjzvoELJ6t9g7ooFFz4rO4DkwoGOQBYH75n5m/3VYnYYUaCNLU9/JbNs91PYOTTCqczKUtVnbVaBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789209506; c=relaxed/simple; bh=82N3kRlnKbkam+C+bJtp280hhL2rXxozvhyJFLw2RLU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=M4Rig6+Zb1qMsUQasA3o0UYGYn28C6a8/rXtePFxlOgNcHDNPPLm7f9+8tGWKvAzQLtx47a1NzHGEFKa5OIJEYEdmpTmDL4tm42thCR1cYZHpZIx3WOpRiafih8nJ/jWUQbZ/1ttYElUgKxJ+3kXxdrGzHyWrxzFNiF6DN0Na5Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=i1vhqUMv; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="i1vhqUMv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1DF91F000FF; Sat, 12 Sep 2026 10:38:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789209503; bh=TACheS7F6OTvtxhlZm1q+24OHVNc9X/qhdfQSZoxJPg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=i1vhqUMvCDxtg9iiFJvws837PeArQVskI2YiBhy2R+TwhnBWVP9lkFtVkf8+geDhP rJb7HiDt2rfbAgHOljLBbNPJG84lweG0i1k/IxJRUr1okFegSEDBnRCz7XaExoDtKO ILcAacTTSgkUVxzWgpJ2lt2fHdeDYd2l8oaHaBWs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Laxman Acharya Padhya , Tzung-Bi Shih , Sasha Levin Subject: [PATCH 6.18 0827/1518] firmware: coreboot: Validate table bounds Date: Sat, 12 Sep 2026 08:49:56 +0200 Message-ID: <20260912065642.147604614@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065623.398859879@linuxfoundation.org> References: <20260912065623.398859879@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Laxman Acharya Padhya [ Upstream commit a58a57a1076f8c5dae0327e3710899478c3be901 ] The existing coreboot_table_populate() bounds checks limit individual entries to the mapped length. However, coreboot_table_probe() replaces the platform resource length with header and table sizes supplied by firmware before mapping the full table. A malformed table can overflow the 32-bit size addition or advertise an extent beyond the resource, causing the driver to map and parse memory outside the resource. A resource shorter than the fixed header is also mapped as though it contained a complete header. Reject resources shorter than the fixed header. After validating the signature, require a complete header, calculate the advertised extent with overflow checking, and reject extents beyond the resource before remapping the table. Fixes: d384d6f43d1e ("firmware: google memconsole: Add coreboot support") Signed-off-by: Laxman Acharya Padhya Link: https://lore.kernel.org/r/20260801165651.42172-1-acharyalaxman8848@gmail.com Signed-off-by: Tzung-Bi Shih Signed-off-by: Sasha Levin --- drivers/firmware/google/coreboot_table.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/google/coreboot_table.c b/drivers/firmware/google/coreboot_table.c index f212b84ee2f93..2f1122635098b 100644 --- a/drivers/firmware/google/coreboot_table.c +++ b/drivers/firmware/google/coreboot_table.c @@ -159,6 +159,7 @@ static int coreboot_table_populate(struct device *dev, void *ptr, resource_size_ static int coreboot_table_probe(struct platform_device *pdev) { resource_size_t len; + resource_size_t table_span; struct coreboot_table_header *header; struct resource *res; struct device *dev = &pdev->dev; @@ -170,7 +171,7 @@ static int coreboot_table_probe(struct platform_device *pdev) return -EINVAL; len = resource_size(res); - if (!res->start || !len) + if (!res->start || len < sizeof(*header)) return -EINVAL; /* Check just the header first to make sure things are sane */ @@ -178,19 +179,27 @@ static int coreboot_table_probe(struct platform_device *pdev) if (!header) return -ENOMEM; - len = header->header_bytes + header->table_bytes; ret = strncmp(header->signature, "LBIO", sizeof(header->signature)); + + if (!ret && + (header->header_bytes < sizeof(*header) || + check_add_overflow((resource_size_t)header->header_bytes, + (resource_size_t)header->table_bytes, + &table_span) || + table_span > len)) + ret = -EINVAL; + memunmap(header); if (ret) { dev_warn(dev, "coreboot table missing or corrupt!\n"); return -ENODEV; } - ptr = memremap(res->start, len, MEMREMAP_WB); + ptr = memremap(res->start, table_span, MEMREMAP_WB); if (!ptr) return -ENOMEM; - ret = coreboot_table_populate(dev, ptr, len); + ret = coreboot_table_populate(dev, ptr, table_span); memunmap(ptr); -- 2.53.0