From nobody Mon Apr 6 03:12:24 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1A8EC54EE9 for ; Sun, 11 Sep 2022 04:41:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229614AbiIKElM (ORCPT ); Sun, 11 Sep 2022 00:41:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229636AbiIKElJ (ORCPT ); Sun, 11 Sep 2022 00:41:09 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F8B541D17; Sat, 10 Sep 2022 21:41:07 -0700 (PDT) Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4MQH7G6hG9zHnkn; Sun, 11 Sep 2022 12:39:06 +0800 (CST) Received: from kwepemm600013.china.huawei.com (7.193.23.68) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Sun, 11 Sep 2022 12:41:05 +0800 Received: from huawei.com (10.175.127.227) by kwepemm600013.china.huawei.com (7.193.23.68) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Sun, 11 Sep 2022 12:41:04 +0800 From: Zhihao Cheng To: , , CC: , , , Subject: [PATCH v2] ext4: Fix dir corruption when ext4_dx_add_entry() fails Date: Sun, 11 Sep 2022 12:52:04 +0800 Message-ID: <20220911045204.516460-1-chengzhihao1@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemm600013.china.huawei.com (7.193.23.68) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Following process may lead to fs corruption: 1. ext4_create(dir/foo) ext4_add_nondir ext4_add_entry ext4_dx_add_entry a. add_dirent_to_buf ext4_mark_inode_dirty ext4_handle_dirty_metadata // dir inode bh is recorded into journal b. ext4_append // dx_get_count(entries) =3D=3D dx_get_limit(entries) ext4_bread(EXT4_GET_BLOCKS_CREATE) ext4_getblk ext4_map_blocks ext4_ext_map_blocks ext4_mb_new_blocks dquot_alloc_block dquot_alloc_space_nodirty inode_add_bytes // update dir's i_blocks ext4_ext_insert_extent ext4_ext_dirty // record extent bh into journal ext4_handle_dirty_metadata(bh) // record new block into journal inode->i_size +=3D inode->i_sb->s_blocksize // new size(in mem) c. ext4_handle_dirty_dx_node(bh2) // record dir's new block(dx_node) into journal d. ext4_handle_dirty_dx_node((frame - 1)->bh) e. ext4_handle_dirty_dx_node(frame->bh) f. do_split // ret err! g. add_dirent_to_buf ext4_mark_inode_dirty(dir) // update raw_inode on disk(skipped) 2. fsck -a /dev/sdb drop last block(dx_node) which beyonds dir's i_size. /dev/sdb: recovering journal /dev/sdb contains a file system with errors, check forced. /dev/sdb: Inode 12, end of extent exceeds allowed value (logical block 128, physical block 3938, len 1) 3. fsck -fn /dev/sdb dx_node->entry[i].blk > dir->i_size Pass 2: Checking directory structure Problem in HTREE directory inode 12 (/dir): bad block number 128. Clear HTree index? no Problem in HTREE directory inode 12: block #3 has invalid depth (2) Problem in HTREE directory inode 12: block #3 has bad max hash Problem in HTREE directory inode 12: block #3 not referenced Fix it by marking inode dirty directly inside ext4_append(). Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=3D216466 CC: stable@vger.kernel.org Signed-off-by: Zhihao Cheng Reviewed-by: Jan Kara --- v1->v2: mark inode dirty inside ext4_append(). fs/ext4/namei.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 3a31b662f661..0d0e41d2dee8 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -85,15 +85,20 @@ static struct buffer_head *ext4_append(handle_t *handle, return bh; inode->i_size +=3D inode->i_sb->s_blocksize; EXT4_I(inode)->i_disksize =3D inode->i_size; + err =3D ext4_mark_inode_dirty(handle, inode); + if (err) + goto out; BUFFER_TRACE(bh, "get_write_access"); err =3D ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE); - if (err) { - brelse(bh); - ext4_std_error(inode->i_sb, err); - return ERR_PTR(err); - } + if (err) + goto out; return bh; + +out: + brelse(bh); + ext4_std_error(inode->i_sb, err); + return ERR_PTR(err); } =20 static int ext4_dx_csum_verify(struct inode *inode, --=20 2.31.1