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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 56501C433F4 for ; Sat, 22 Sep 2018 00:21:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F39A92157C for ; Sat, 22 Sep 2018 00:21:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F39A92157C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392179AbeIVGMw (ORCPT ); Sat, 22 Sep 2018 02:12:52 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44248 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392013AbeIVGKt (ORCPT ); Sat, 22 Sep 2018 02:10:49 -0400 Received: from [2a02:8011:400e:2:cbab:f00:c93f:614] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1g3Vdy-0008BR-7D; Sat, 22 Sep 2018 01:19:30 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1g3Vdo-0000sQ-8p; Sat, 22 Sep 2018 01:19:20 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Theodore Ts'o" Date: Sat, 22 Sep 2018 01:15:42 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 34/63] ext4: clear i_data in ext4_inode_info when removing inline data In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:cbab:f00:c93f:614 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.58-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Theodore Ts'o commit 6e8ab72a812396996035a37e5ca4b3b99b5d214b upstream. When converting from an inode from storing the data in-line to a data block, ext4_destroy_inline_data_nolock() was only clearing the on-disk copy of the i_blocks[] array. It was not clearing copy of the i_blocks[] in ext4_inode_info, in i_data[], which is the copy actually used by ext4_map_blocks(). This didn't matter much if we are using extents, since the extents header would be invalid and thus the extents could would re-initialize the extents tree. But if we are using indirect blocks, the previous contents of the i_blocks array will be treated as block numbers, with potentially catastrophic results to the file system integrity and/or user data. This gets worse if the file system is using a 1k block size and s_first_data is zero, but even without this, the file system can get quite badly corrupted. This addresses CVE-2018-10881. https://bugzilla.kernel.org/show_bug.cgi?id=200015 Signed-off-by: Theodore Ts'o Signed-off-by: Ben Hutchings --- fs/ext4/inline.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -438,6 +438,7 @@ static int ext4_destroy_inline_data_nolo memset((void *)ext4_raw_inode(&is.iloc)->i_block, 0, EXT4_MIN_INLINE_DATA_SIZE); + memset(ei->i_data, 0, EXT4_MIN_INLINE_DATA_SIZE); if (EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {