From 4d6b6df822fa2c41c32dc548b8156d3c8531fd5a Mon Sep 17 00:00:00 2001 From: Li Lingfeng Date: Fri, 17 Jun 2022 14:25:15 +0800 Subject: [PATCH] ext4: recover csum seed of tmp_inode after migrating to extents [ Upstream commit 3609731dd52c06b6eca15724ab3b7b07889dc3ad ] When migrating to extents, the checksum seed of temporary inode need to be replaced by inode's, otherwise the inode checksums will be incorrect when swapping the inodes data. However, the temporary inode can not match it's checksum to itself since it has lost it's own checksum seed. mkfs.ext4 -F /dev/sdc mount /dev/sdc /mnt/sdc xfs_io -fc "pwrite 4k 4k" -c "fsync" /mnt/sdc/testfile chattr -e /mnt/sdc/testfile chattr +e /mnt/sdc/testfile umount /dev/sdc fsck -fn /dev/sdc ======== ... Pass 1: Checking inodes, blocks, and sizes Inode 13 passes checks, but checksum does not match inode. Fix? no ... ======== The fix is simple, save the checksum seed of temporary inode, and recover it after migrating to extents. Fixes: 66a4d8deef8a ("ext4: set csum seed in tmp inode while migrating to extents") Signed-off-by: Li Lingfeng Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220617062515.2113438-1-lilingfeng3@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/migrate.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c index ff8916e1d38e9..af5a75a89e6e1 100644 --- a/fs/ext4/migrate.c +++ b/fs/ext4/migrate.c @@ -417,7 +417,7 @@ int ext4_ext_migrate(struct inode *inode) struct inode *tmp_inode = NULL; struct migrate_struct lb; unsigned long max_entries; - __u32 goal; + __u32 goal, tmp_csum_seed; uid_t owner[2]; /* @@ -465,6 +465,7 @@ int ext4_ext_migrate(struct inode *inode) * the migration. */ ei = EXT4_I(inode); + tmp_csum_seed = EXT4_I(tmp_inode)->i_csum_seed; EXT4_I(tmp_inode)->i_csum_seed = ei->i_csum_seed; i_size_write(tmp_inode, i_size_read(inode)); /* @@ -575,6 +576,7 @@ err_out: * the inode is not visible to user space. */ tmp_inode->i_blocks = 0; + EXT4_I(tmp_inode)->i_csum_seed = tmp_csum_seed; /* Reset the extent details */ ext4_ext_tree_init(handle, tmp_inode); -- 2.39.5