From nobody Mon Apr 13 20:05:39 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 7332FC433FE for ; Thu, 17 Nov 2022 03:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234157AbiKQDmd (ORCPT ); Wed, 16 Nov 2022 22:42:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234640AbiKQDmX (ORCPT ); Wed, 16 Nov 2022 22:42:23 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F2CF54B0A; Wed, 16 Nov 2022 19:42:23 -0800 (PST) Received: from dggpeml500021.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NCQhQ6GgLz15MZk; Thu, 17 Nov 2022 11:41:58 +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; Thu, 17 Nov 2022 11:42:20 +0800 From: Baokun Li To: CC: , , , , , , , Subject: [PATCH v3 3/3] ext4: fix corruption when online resizing a 1K bigalloc fs Date: Thu, 17 Nov 2022 12:03:41 +0800 Message-ID: <20221117040341.1380702-4-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221117040341.1380702-1-libaokun1@huawei.com> References: <20221117040341.1380702-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) 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 ext4_group_first_block_no() 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 Reviewed-by: Jan Kara --- V1->V2: Replace s_first_data_block with ext4_group_first_block_no() to avoid type warning.(Reported-by: kernel test robot ) 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 66ceabbd83ad..b493233750ab 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1604,8 +1604,8 @@ 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, - sizeof(struct ext4_super_block), 0); + update_backups(sb, ext4_group_first_block_no(sb, 0), + (char *)es, sizeof(struct ext4_super_block), 0); for (; gdb_num <=3D gdb_num_end; gdb_num++) { struct buffer_head *gdb_bh; =20 @@ -1816,7 +1816,7 @@ 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, + update_backups(sb, ext4_group_first_block_no(sb, 0), (char *)es, sizeof(struct ext4_super_block), 0); } return err; --=20 2.31.1