[PATCH] fs/ntfs3: check wnd_set_used() in ntfs_look_free_mft()

[Baolin Liu]

From: Baolin Liu <liubaolin@xxxxxxxxxx>

wnd_set_used() can fail, but ntfs_look_free_mft() ignored
the error and could return success after leaving the MFT
bitmap unmarked.

Check the return value and unwind the new subrecord on failure.

Signed-off-by: Baolin Liu <liubaolin@xxxxxxxxxx>
---
 fs/ntfs3/fsntfs.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/fs/ntfs3/fsntfs.c b/fs/ntfs3/fsntfs.c
index d0434756029b..ab9e03156cce 100644
--- a/fs/ntfs3/fsntfs.c
+++ b/fs/ntfs3/fsntfs.c
@@ -741,10 +741,19 @@ int ntfs_look_free_mft(struct ntfs_sb_info *sbi, CLST *rno, bool mft,
 	}
 
 	/* We have found a record that are not reserved for next MFT. */
-	if (*rno >= MFT_REC_FREE)
-		wnd_set_used(wnd, *rno, 1);
-	else if (*rno >= MFT_REC_RESERVED && sbi->mft.reserved_bitmap_inited)
+	if (*rno >= MFT_REC_FREE) {
+		err = wnd_set_used(wnd, *rno, 1);
+		if (err) {
+			if (ni) {
+				ni_remove_mi(ni, *mi);
+				mi_put(*mi);
+				*mi = NULL;
+			}
+			goto out;
+		}
+	} else if (*rno >= MFT_REC_RESERVED && sbi->mft.reserved_bitmap_inited) {
 		__set_bit(*rno - MFT_REC_RESERVED, &sbi->mft.reserved_bitmap);
+	}
 
 out:
 	if (!mft)
-- 
2.51.0