From nobody Mon Apr 13 18:31:10 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 C6731C4332F for ; Tue, 15 Nov 2022 11:55:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231389AbiKOLzg (ORCPT ); Tue, 15 Nov 2022 06:55:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230039AbiKOLzR (ORCPT ); Tue, 15 Nov 2022 06:55:17 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ABC0113D09; Tue, 15 Nov 2022 03:55:16 -0800 (PST) Received: from dggpeml500021.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4NBPjw3hnmzHvrS; Tue, 15 Nov 2022 19:54:44 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500021.china.huawei.com (7.185.36.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 15 Nov 2022 19:55:14 +0800 From: Baokun Li To: CC: , , , , , , , Subject: [PATCH 3/3] ext4: fix corruption when online resizing a 1K bigalloc fs Date: Tue, 15 Nov 2022 20:16:38 +0800 Message-ID: <20221115121638.192349-4-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221115121638.192349-1-libaokun1@huawei.com> References: <20221115121638.192349-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpeml500021.china.huawei.com (7.185.36.21) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When a backup superblock is updated in update_backups(), the primary superblock's offset in the group (that is, sbi->s_sbh->b_blocknr) is used as the backup superblock's offset in its group. However, when the block size is 1K and bigalloc is enabled, the two offsets are not equal. This causes the backup group descriptors to be overwritten by the superblock in update_backups(). Moreover, if meta_bg is enabled, the file system will be corrupted because this feature uses backup group descriptors. To solve this issue, we use a more accurate s_first_data_block as the offset of the backup superblock in its group. Fixes: d77147ff443b ("ext4: add support for online resizing with bigalloc") Signed-off-by: Baokun Li --- fs/ext4/resize.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 32fbfc173571..cf75fdd3729d 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1591,7 +1591,7 @@ static int ext4_flex_group_add(struct super_block *sb, int meta_bg =3D ext4_has_feature_meta_bg(sb); sector_t old_gdb =3D 0; =20 - update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, + update_backups(sb, es->s_first_data_block, (char *)es, sizeof(struct ext4_super_block), 0); for (; gdb_num <=3D gdb_num_end; gdb_num++) { struct buffer_head *gdb_bh; @@ -1803,8 +1803,8 @@ static int ext4_group_extend_no_check(struct super_bl= ock *sb, if (test_opt(sb, DEBUG)) printk(KERN_DEBUG "EXT4-fs: extended group to %llu " "blocks\n", ext4_blocks_count(es)); - update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, - (char *)es, sizeof(struct ext4_super_block), 0); + update_backups(sb, es->s_first_data_block, (char *)es, + sizeof(struct ext4_super_block), 0); } return err; } --=20 2.31.1