xfs: directory scrubber must walk through data block to offset

In xfs_scrub_dir_rec, we must walk through the directory block entries
to arrive at the offset given by the hash structure.  If we blindly
trust the hash address, we can end up midway into a directory entry and
stray outside the block.  Found by lastbit fuzzing lents[3].address in
xfs/390 with KASAN enabled.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
This commit is contained in:
Darrick J. Wong
2018-01-16 18:54:12 -08:00
parent 638a717489
commit ce92d29ddf
5 changed files with 58 additions and 33 deletions

View File

@@ -340,5 +340,7 @@ xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
#define XFS_READDIR_BUFSIZE (32768)
unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
struct xfs_dir2_data_hdr *hdr);
#endif /* __XFS_DIR2_H__ */