[PATCH 5.10 373/406] btrfs: use the correct superblock to compare fsid in btrfs_validate_super

Greg Kroah-Hartman
2023-09-17T19:41:48Z

From: Anand Jain <anand.jain@oracle.com>

commit d167aa76dc0683828588c25767da07fb549e4f48 upstream.

The function btrfs_validate_super() should verify the fsid in the provided
superblock argument. Because, all its callers expect it to do that.

Such as in the following stack:

write_all_supers()
sb = fs_info->super_for_commit;
btrfs_validate_write_super(.., sb)
btrfs_validate_super(.., sb, ..)

scrub_one_super()
btrfs_validate_super(.., sb, ..)

And
check_dev_super()
btrfs_validate_super(.., sb, ..)

However, it currently verifies the fs_info::super_copy::fsid instead,
which is not correct. Fix this using the correct fsid in the superblock
argument.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/btrfs/disk-io.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2496,11 +2496,10 @@ static int validate_super(struct btrfs_f
ret = -EINVAL;
}

- if (memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid,
- BTRFS_FSID_SIZE)) {
+ if (memcmp(fs_info->fs_devices->fsid, sb->fsid, BTRFS_FSID_SIZE) != 0) {
btrfs_err(fs_info,
"superblock fsid doesn't match fsid of fs_devices: %pU != %pU",
- fs_info->super_copy->fsid, fs_info->fs_devices->fsid);
+ sb->fsid, fs_info->fs_devices->fsid);
ret = -EINVAL;
}