xfs: enhance dinode verifier

Add several more validations to xfs_dinode_verify:

- For LOCAL data fork formats, di_nextents must be 0.
- For LOCAL attr fork formats, di_anextents must be 0.
- For inodes with no attr fork offset,
  - format must be XFS_DINODE_FMT_EXTENTS if set at all
  - di_anextents must be 0.

Thanks to dchinner for pointing out a couple related checks I had
forgotten to add.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199377
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This commit is contained in:
Eric Sandeen 2018-04-16 23:06:53 -07:00 committed by Darrick J. Wong
parent 60cc43fc88
commit b42db0860e

View File

@ -466,6 +466,8 @@ xfs_dinode_verify(
return __this_address;
if (di_size > XFS_DFORK_DSIZE(dip, mp))
return __this_address;
if (dip->di_nextents)
return __this_address;
/* fall through */
case XFS_DINODE_FMT_EXTENTS:
case XFS_DINODE_FMT_BTREE:
@ -484,12 +486,31 @@ xfs_dinode_verify(
if (XFS_DFORK_Q(dip)) {
switch (dip->di_aformat) {
case XFS_DINODE_FMT_LOCAL:
if (dip->di_anextents)
return __this_address;
/* fall through */
case XFS_DINODE_FMT_EXTENTS:
case XFS_DINODE_FMT_BTREE:
break;
default:
return __this_address;
}
} else {
/*
* If there is no fork offset, this may be a freshly-made inode
* in a new disk cluster, in which case di_aformat is zeroed.
* Otherwise, such an inode must be in EXTENTS format; this goes
* for freed inodes as well.
*/
switch (dip->di_aformat) {
case 0:
case XFS_DINODE_FMT_EXTENTS:
break;
default:
return __this_address;
}
if (dip->di_anextents)
return __this_address;
}
/* only version 3 or greater inodes are extensively verified here */