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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 8909CCA9EB9 for ; Sat, 26 Oct 2019 13:28:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 556B220867 for ; Sat, 26 Oct 2019 13:28:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572096522; bh=UK7m25F9ZMBaMWRSv7Q+Giy/+sHLZXHNYPoDUZnqReA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cGq/n53f0WO0zdN7cgA4IAhJ7IDoAoSP57Xj/OJewSeGQIMt5rf/qdTr3eTHc6MZ7 9jdy5330ixxK6Dku0IhcaEULg/KIsJRMT8uEoQ94xQyMqiV/WVgPdUn+RjxqtHrbZR f2v9zfS6AYMh8caG8aNbSS12pkUM69187Or5WGww= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728728AbfJZNUz (ORCPT ); Sat, 26 Oct 2019 09:20:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:42374 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728662AbfJZNUh (ORCPT ); Sat, 26 Oct 2019 09:20:37 -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 F0C2E214DA; Sat, 26 Oct 2019 13:20:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572096036; bh=UK7m25F9ZMBaMWRSv7Q+Giy/+sHLZXHNYPoDUZnqReA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mgYkX2l7l1I7nPvzxO5v8pnTrxrQvQ6wFf5BTQMtUAy32wW/SKq05NWcJTNH64+Mh V/FkipgYTSKLbRqr1Ai0fsBGazX34UVuno6VQ3Sty/O8QKg16KpUNEUrko12ZhZDFp EWMYUjkYGYPTfpOhwUeBGoJeWfn2L5lEPIkVASbk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jean Delvare , Tony Luck , Borislav Petkov , Sasha Levin Subject: [PATCH AUTOSEL 4.19 45/59] firmware: dmi: Fix unlikely out-of-bounds read in save_mem_devices Date: Sat, 26 Oct 2019 09:18:56 -0400 Message-Id: <20191026131910.3435-45-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191026131910.3435-1-sashal@kernel.org> References: <20191026131910.3435-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review 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: Jean Delvare [ Upstream commit 81dde26de9c08bb04c4962a15608778aaffb3cf9 ] Before reading the Extended Size field, we should ensure it fits in the DMI record. There is already a record length check but it does not cover that field. It would take a seriously corrupted DMI table to hit that bug, so no need to worry, but we should still fix it. Signed-off-by: Jean Delvare Fixes: 6deae96b42eb ("firmware, DMI: Add function to look up a handle and return DIMM size") Cc: Tony Luck Cc: Borislav Petkov Signed-off-by: Sasha Levin --- drivers/firmware/dmi_scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index f2483548cde92..0dc0c78f1fdb2 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -407,7 +407,7 @@ static void __init save_mem_devices(const struct dmi_header *dm, void *v) bytes = ~0ull; else if (size & 0x8000) bytes = (u64)(size & 0x7fff) << 10; - else if (size != 0x7fff) + else if (size != 0x7fff || dm->length < 0x20) bytes = (u64)size << 20; else bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20; -- 2.20.1