xfs: scrub should flag dir/attr offsets that aren't mappable with xfs_dablk_t

Teach scrub to flag extent maps that exceed the range that can be mapped
with a xfs_dablk_t.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

2 files changed, 12 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c
index 3306fc42cfad..451608b5a37b 100644
--- a/fs/xfs/libxfs/xfs_types.c
+++ b/fs/xfs/libxfs/xfs_types.c
@@ -204,3 +204,14 @@ xfs_verify_icount(
         xfs_icount_range(mp, &min, &max);
         return icount >= min && icount <= max;
 }
+
+/* Sanity-checking of dir/attr block offsets. */
+bool
+xfs_verify_dablk(
+        struct xfs_mount        *mp,
+        xfs_fileoff_t           dabno)
+{
+        xfs_dablk_t             max_dablk = -1U;
+
+        return dabno <= max_dablk;
+}
diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h
index 8f02855a019a..704b4f308780 100644
--- a/fs/xfs/libxfs/xfs_types.h
+++ b/fs/xfs/libxfs/xfs_types.h
@@ -188,5 +188,6 @@ bool xfs_internal_inum(struct xfs_mount *mp, xfs_ino_t ino);
 bool xfs_verify_dir_ino(struct xfs_mount *mp, xfs_ino_t ino);
 bool xfs_verify_rtbno(struct xfs_mount *mp, xfs_rtblock_t rtbno);
 bool xfs_verify_icount(struct xfs_mount *mp, unsigned long long icount);
+bool xfs_verify_dablk(struct xfs_mount *mp, xfs_fileoff_t off);
 
 #endif  /* __XFS_TYPES_H__ */