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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 C7915C43381 for ; Wed, 27 Mar 2019 19:06:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A0D0206BA for ; Wed, 27 Mar 2019 19:06:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553713564; bh=O5LEgMVOmHt8QJYgkL4OQn28TaFUOK0sNvyHudogbus=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Fvm7lcCDjwqkiK2pwjMzn1uJDIYwYqfi8v+yq3IhDR/QK1t3Dv2FNoECsN2Tz+fTV HQPC4dMmDwxB21GVruXVKhlHEzRsLeCBH9OUpqcaqEa/x/aQYZXZUwzjTGSi+88ApM Lld3NokXHCbBYZTWRzUPfil//FZH649j+9kCoJ9g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389629AbfC0TGC (ORCPT ); Wed, 27 Mar 2019 15:06:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:54994 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388997AbfC0SMd (ORCPT ); Wed, 27 Mar 2019 14:12:33 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 73F2E2184C; Wed, 27 Mar 2019 18:12:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710353; bh=O5LEgMVOmHt8QJYgkL4OQn28TaFUOK0sNvyHudogbus=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R1YdDyJPnUjD3U/xd7wBq9FzZqp68xr/yQOcTfH3y6IckIgJ++WItZhtuBH13FWTu DkBJcJu4MDkTTKn9fczvaGIHA85JdWOPWloHv6Eg2B0GirR8t7YCid9gGq96LBKIRR 6C/7/Tkx5yA7n2T0NxYs1Q8y3SiPqVKT7sQDmChw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ross Lagerwall , "Rafael J . Wysocki" , Sasha Levin , linux-efi@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 075/192] efi: cper: Fix possible out-of-bounds access Date: Wed, 27 Mar 2019 14:08:27 -0400 Message-Id: <20190327181025.13507-75-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327181025.13507-1-sashal@kernel.org> References: <20190327181025.13507-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ross Lagerwall [ Upstream commit 45b14a4ffcc1e0b5caa246638f942cbe7eaea7ad ] When checking a generic status block, we iterate over all the generic data blocks. The loop condition only checks that the start of the generic data block is valid (within estatus->data_length) but not the whole block. Because the size of data blocks (excluding error data) may vary depending on the revision and the revision is contained within the data block, ensure that enough of the current data block is valid before dereferencing any members otherwise an out-of-bounds access may occur if estatus->data_length is invalid. This relies on the fact that struct acpi_hest_generic_data_v300 is a superset of the earlier version. Also rework the other checks to avoid potential underflow. Signed-off-by: Ross Lagerwall Acked-by: Borislav Petkov Tested-by: Tyler Baicar Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/firmware/efi/cper.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c index a7902fccdcfa..6090d25dce85 100644 --- a/drivers/firmware/efi/cper.c +++ b/drivers/firmware/efi/cper.c @@ -546,19 +546,24 @@ EXPORT_SYMBOL_GPL(cper_estatus_check_header); int cper_estatus_check(const struct acpi_hest_generic_status *estatus) { struct acpi_hest_generic_data *gdata; - unsigned int data_len, gedata_len; + unsigned int data_len, record_size; int rc; rc = cper_estatus_check_header(estatus); if (rc) return rc; + data_len = estatus->data_length; apei_estatus_for_each_section(estatus, gdata) { - gedata_len = acpi_hest_get_error_length(gdata); - if (gedata_len > data_len - acpi_hest_get_size(gdata)) + if (sizeof(struct acpi_hest_generic_data) > data_len) + return -EINVAL; + + record_size = acpi_hest_get_record_size(gdata); + if (record_size > data_len) return -EINVAL; - data_len -= acpi_hest_get_record_size(gdata); + + data_len -= record_size; } if (data_len) return -EINVAL; -- 2.19.1