[PATCH v1 9/9] ntfs: skip free cluster decrement when rollback fails

[Baolin Liu]

From: Baolin Liu <liubaolin@xxxxxxxxxx>

When the rollback in __ntfs_cluster_free() fails, the recursive
call returns a negative errno and the subsequent
ntfs_dec_free_clusters(vol, delta) subtracts that negative value,
adding bogus clusters to the counter on an already-failing volume.

Skip the decrement when the rollback failed.

Fixes: 11ccc9107dc4 ("ntfs: update runlist handling and cluster allocator")
Signed-off-by: Baolin Liu <liubaolin@xxxxxxxxxx>
---
 fs/ntfs/lcnalloc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ntfs/lcnalloc.c b/fs/ntfs/lcnalloc.c
index 795f71d26895..0d6cd08ee2e7 100644
--- a/fs/ntfs/lcnalloc.c
+++ b/fs/ntfs/lcnalloc.c
@@ -1045,8 +1045,9 @@ s64 __ntfs_cluster_free(struct ntfs_inode *ni, const s64 start_vcn, s64 count,
 			"Failed to rollback (error %i).  Leaving inconsistent metadata!  Unmount and run chkdsk.",
 			(int)delta);
 		NVolSetErrors(vol);
+	} else {
+		ntfs_dec_free_clusters(vol, delta);
 	}
-	ntfs_dec_free_clusters(vol, delta);
 	up_write(&vol->lcnbmp_lock);
 	memalloc_nofs_restore(memalloc_flags);
 	ntfs_error(vol->sb, "Aborting (error %i).", err);
-- 
2.51.0