diff options
| author | Qu Wenruo <wqu@suse.com> | 2019-08-28 10:33:13 +0800 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2019-10-25 19:11:34 +0200 |
| commit | 8bb177d18f114358a57d8ae7e206861b48b8b4de (patch) | |
| tree | aeb0c1486a1a17ad679ca46fa2f5ab0e60e12033 /fs | |
| parent | c17add7a1c61a15578e4071ed7bfd460fd041c43 (diff) | |
btrfs: tree-checker: Fix wrong check on max devid
[BUG]
The following script will cause false alert on devid check.
#!/bin/bash
dev1=/dev/test/test
dev2=/dev/test/scratch1
mnt=/mnt/btrfs
umount $dev1 &> /dev/null
umount $dev2 &> /dev/null
umount $mnt &> /dev/null
mkfs.btrfs -f $dev1
mount $dev1 $mnt
_fail()
{
echo "!!! FAILED !!!"
exit 1
}
for ((i = 0; i < 4096; i++)); do
btrfs dev add -f $dev2 $mnt || _fail
btrfs dev del $dev1 $mnt || _fail
dev_tmp=$dev1
dev1=$dev2
dev2=$dev_tmp
done
[CAUSE]
Tree-checker uses BTRFS_MAX_DEVS() and BTRFS_MAX_DEVS_SYS_CHUNK() as
upper limit for devid. But we can have devid holes just like above
script.
So the check for devid is incorrect and could cause false alert.
[FIX]
Just remove the whole devid check. We don't have any hard requirement
for devid assignment.
Furthermore, even devid could get corrupted by a bitflip, we still have
dev extents verification at mount time, so corrupted data won't sneak
in.
This fixes fstests btrfs/194.
Reported-by: Anand Jain <anand.jain@oracle.com>
Fixes: ab4ba2e13346 ("btrfs: tree-checker: Verify dev item")
CC: stable@vger.kernel.org # 5.2+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/tree-checker.c | 8 |
1 files changed, 0 insertions, 8 deletions
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index 43e488f5d063..076d5b8014fb 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -686,9 +686,7 @@ static void dev_item_err(const struct extent_buffer *eb, int slot, static int check_dev_item(struct extent_buffer *leaf, struct btrfs_key *key, int slot) { - struct btrfs_fs_info *fs_info = leaf->fs_info; struct btrfs_dev_item *ditem; - u64 max_devid = max(BTRFS_MAX_DEVS(fs_info), BTRFS_MAX_DEVS_SYS_CHUNK); if (key->objectid != BTRFS_DEV_ITEMS_OBJECTID) { dev_item_err(leaf, slot, @@ -696,12 +694,6 @@ static int check_dev_item(struct extent_buffer *leaf, key->objectid, BTRFS_DEV_ITEMS_OBJECTID); return -EUCLEAN; } - if (key->offset > max_devid) { - dev_item_err(leaf, slot, - "invalid devid: has=%llu expect=[0, %llu]", - key->offset, max_devid); - return -EUCLEAN; - } ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item); if (btrfs_device_id(leaf, ditem) != key->offset) { dev_item_err(leaf, slot, |