When ancestor is less than IS_ANCESTOR_BITMAP, we would get an incorrect result.
Signed-off-by: Alan Huang <[email protected]> --- fs/bcachefs/snapshot.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/bcachefs/snapshot.c b/fs/bcachefs/snapshot.c index c54091a28909..ede0b480e7d4 100644 --- a/fs/bcachefs/snapshot.c +++ b/fs/bcachefs/snapshot.c @@ -146,8 +146,9 @@ bool __bch2_snapshot_is_ancestor(struct bch_fs *c, u32 id, u32 ancestor) goto out; } - while (id && id < ancestor - IS_ANCESTOR_BITMAP) - id = get_ancestor_below(t, id, ancestor); + if (likely(ancestor >= IS_ANCESTOR_BITMAP)) + while (id && id < ancestor - IS_ANCESTOR_BITMAP) + id = get_ancestor_below(t, id, ancestor); ret = id && id < ancestor ? test_ancestor_bitmap(t, id, ancestor) -- 2.47.0
