btrfs-progs: Fix a bug in reset_nlink() which may deletes the recovered file

In reset_nlink(), we believe rec->found_link as accurate number of the
valid links. However it only records the number of found DIR_ITEM, so we
can't use it as reliable value.

Before this patch, in some case, leaf corruption recovery will believe
there is a valid backref but don't add_link() since it can't find any
valid one and don't put it into the lost+found dir.
So the recovered inode will be considered as an orphan item without
orphan item and repair_inode_orphan_item() will add orphan item for it,
causing all the filename/filetype we recovered being a waste of time.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
master
Qu Wenruo 2014-12-23 09:29:44 +08:00 committed by David Sterba
parent 44d3ee3e1f
commit 0f38766b8f
1 changed files with 5 additions and 0 deletions

View File

@ -1959,6 +1959,9 @@ static int reset_nlink(struct btrfs_trans_handle *trans,
struct btrfs_inode_item *inode_item;
int ret = 0;
/* We don't believe this either, reset it and iterate backref */
rec->found_link = 0;
/* Remove all backref including the valid ones */
list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
ret = btrfs_unlink(trans, root, rec->ino, backref->dir,
@ -1973,6 +1976,8 @@ static int reset_nlink(struct btrfs_trans_handle *trans,
backref->found_inode_ref)) {
list_del(&backref->list);
free(backref);
} else {
rec->found_link++;
}
}