The boundary test for the fixed-offset parts of xfs_attr_sf_entry in
xfs_attr_shortform_verify is off by one, because the variable array
at the end is defined as nameval[1] not nameval[].
Hence we need to subtract 1 from the calculation.
This can be shown by:
# touch file
# setfattr -n root.a file
and verifications will fail when it's written to disk.
This only matters for a last attribute which has a single-byte name
and no value, otherwise the combination of namelen & valuelen will
push endp further out and this test won't fail.
Fixes:
1e1bbd8e7ee06 ("xfs: create structure verifier function for shortform xattrs")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
* struct xfs_attr_sf_entry has a variable length.
* Check the fixed-offset parts of the structure are
* within the data buffer.
* struct xfs_attr_sf_entry has a variable length.
* Check the fixed-offset parts of the structure are
* within the data buffer.
+ * xfs_attr_sf_entry is defined with a 1-byte variable
+ * array at the end, so we must subtract that off.
- if (((char *)sfep + sizeof(*sfep)) >= endp)
+ if (((char *)sfep + sizeof(*sfep) - 1) >= endp)
return __this_address;
/* Don't allow names with known bad length. */
return __this_address;
/* Don't allow names with known bad length. */