[PATCH 11/9] xfs: flag inode corruption if parent ptr doesn't get us a real inode

["Darrick J. Wong" <darrick.wong@oracle.com>]

From: Darrick J. Wong <darrick.wong@oracle.com>

If a directory's parent inode pointer doesn't point to an inode, flag
the directory as corrupt.  Enable IGET_UNTRUSTED here so that we
can confirm with the inobt that the inode is present and allocated.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/scrub/parent.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/scrub/parent.c b/fs/xfs/scrub/parent.c
index 0d38514..d1547ca 100644
--- a/fs/xfs/scrub/parent.c
+++ b/fs/xfs/scrub/parent.c
@@ -167,9 +167,14 @@ xfs_scrub_parent_validate(
 	 * if the parent pointer erroneously points to a file, we
 	 * can't use DONTCACHE here because DONTCACHE inodes can trigger
 	 * immediate inactive cleanup of the inode.
+	 *
+	 * If _iget returns -EINVAL then the parent inode number is garbage
+	 * and the directory is corrupt.
 	 */
-	error = xfs_iget(mp, sc->tp, dnum, 0, 0, &dp);
-	if (!xfs_scrub_fblock_xref_process_error(sc, XFS_DATA_FORK, 0, &error))
+	error = xfs_iget(mp, sc->tp, dnum, XFS_IGET_UNTRUSTED, 0, &dp);
+	if (error == -EINVAL)
+		error = -EFSCORRUPTED;
+	if (!xfs_scrub_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
 		goto out;
 	if (dp == sc->ip || !S_ISDIR(VFS_I(dp)->i_mode)) {
 		xfs_scrub_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);