diff options
| author | Lizhi Xu <lizhi.xu@windriver.com> | 2024-10-25 12:55:53 +0800 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2024-11-29 16:50:40 +0100 |
| commit | 3ed51857a50f530ac7a1482e069dfbd1298558d4 (patch) | |
| tree | 812aa6b57915b14c468728b0a76eaf9042330bdc /fs | |
| parent | ed67f2a913a4f0fc505db29805c41dd07d3cb356 (diff) | |
btrfs: add a sanity check for btrfs root in btrfs_search_slot()
Syzbot reports a null-ptr-deref in btrfs_search_slot().
The reproducer is using rescue=ibadroots, and the extent tree root is
corrupted thus the extent tree is NULL.
When scrub tries to search the extent tree to gather the needed extent
info, btrfs_search_slot() doesn't check if the target root is NULL or
not, resulting the null-ptr-deref.
Add sanity check for btrfs root before using it in btrfs_search_slot().
Reported-by: syzbot+3030e17bd57a73d39bd7@syzkaller.appspotmail.com
Fixes: 42437a6386ff ("btrfs: introduce mount option rescue=ignorebadroots")
Link: https://syzkaller.appspot.com/bug?extid=3030e17bd57a73d39bd7
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Tested-by: syzbot+3030e17bd57a73d39bd7@syzkaller.appspotmail.com
Signed-off-by: Lizhi Xu <lizhi.xu@windriver.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/ctree.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 148648ea1c8b..693dc27ffb89 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -2046,7 +2046,7 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root, const struct btrfs_key *key, struct btrfs_path *p, int ins_len, int cow) { - struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_fs_info *fs_info; struct extent_buffer *b; int slot; int ret; @@ -2059,6 +2059,10 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root, int min_write_lock_level; int prev_cmp; + if (!root) + return -EINVAL; + + fs_info = root->fs_info; might_sleep(); lowest_level = p->lowest_level; |