xfs: mark dir corrupt when lookup-by-hash fails

In xchk_dir_actor, we attempt to validate the directory hash structures
by performing a directory entry lookup by (hashed) name.  If the lookup
returns ENOENT, that means that the hash information is corrupt.  The
_process_error functions don't catch this, so we have to add that
explicitly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

fs/xfs/scrub/dir.c

@@ -155,6 +155,9 @@ xchk_dir_actor(
 	xname.type = XFS_DIR3_FT_UNKNOWN;
 
 	error = xfs_dir_lookup(sdc->sc->tp, ip, &xname, &lookup_ino, NULL);
+	/* ENOENT means the hash lookup failed and the dir is corrupt */
+	if (error == -ENOENT)
+		error = -EFSCORRUPTED;
 	if (!xchk_fblock_process_error(sdc->sc, XFS_DATA_FORK, offset,
 			&error))
 		goto out;