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,URIBL_BLOCKED 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 E98CCECE560 for ; Sat, 22 Sep 2018 00:22:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A7BEA2159E for ; Sat, 22 Sep 2018 00:22:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A7BEA2159E 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 S2392342AbeIVGNa (ORCPT ); Sat, 22 Sep 2018 02:13:30 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44234 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392004AbeIVGKs (ORCPT ); Sat, 22 Sep 2018 02:10:48 -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-0008Bd-6Y; Sat, 22 Sep 2018 01:19:30 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1g3Vdo-0000s2-2n; 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 29/63] ext4: make sure bitmaps and the inode table don't overlap with bg descriptors 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 77260807d1170a8cf35dbb06e07461a655f67eee upstream. It's really bad when the allocation bitmaps and the inode table overlap with the block group descriptors, since it causes random corruption of the bg descriptors. So we really want to head those off at the pass. https://bugzilla.kernel.org/show_bug.cgi?id=199865 Signed-off-by: Theodore Ts'o [bwh: Backported to 3.16: Open-code sb_rdonly()] Signed-off-by: Ben Hutchings --- fs/ext4/super.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2086,6 +2086,7 @@ static int ext4_check_descriptors(struct struct ext4_sb_info *sbi = EXT4_SB(sb); ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); ext4_fsblk_t last_block; + ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0) + 1; ext4_fsblk_t block_bitmap; ext4_fsblk_t inode_bitmap; ext4_fsblk_t inode_table; @@ -2118,6 +2119,14 @@ static int ext4_check_descriptors(struct if (!(sb->s_flags & MS_RDONLY)) return 0; } + if (block_bitmap >= sb_block + 1 && + block_bitmap <= last_bg_block) { + ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: " + "Block bitmap for group %u overlaps " + "block group descriptors", i); + if (!(sb->s_flags & MS_RDONLY)) + return 0; + } if (block_bitmap < first_block || block_bitmap > last_block) { ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: " "Block bitmap for group %u not in group " @@ -2132,6 +2141,14 @@ static int ext4_check_descriptors(struct if (!(sb->s_flags & MS_RDONLY)) return 0; } + if (inode_bitmap >= sb_block + 1 && + inode_bitmap <= last_bg_block) { + ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: " + "Inode bitmap for group %u overlaps " + "block group descriptors", i); + if (!(sb->s_flags & MS_RDONLY)) + return 0; + } if (inode_bitmap < first_block || inode_bitmap > last_block) { ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: " "Inode bitmap for group %u not in group " @@ -2146,6 +2163,14 @@ static int ext4_check_descriptors(struct if (!(sb->s_flags & MS_RDONLY)) return 0; } + if (inode_table >= sb_block + 1 && + inode_table <= last_bg_block) { + ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: " + "Inode table for group %u overlaps " + "block group descriptors", i); + if (!(sb->s_flags & MS_RDONLY)) + return 0; + } if (inode_table < first_block || inode_table + sbi->s_itb_per_group - 1 > last_block) { ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "