Commit a10c21ed authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: check owner of dir3 data blocks 



Check the owner field of dir3 data block headers.  If it's corrupt,
release the buffer and return EFSCORRUPTED.  All callers handle this
properly.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
parent 6fb5aac7

fs/xfs/libxfs/xfs_dir2_data.c

+30 −2
Original line number Diff line number Diff line
@@ -394,6 +394,22 @@ static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = { 
	.verify_write = xfs_dir3_data_write_verify,

};



static xfs_failaddr_t

xfs_dir3_data_header_check(

	struct xfs_inode	*dp,

	struct xfs_buf		*bp)

{

	struct xfs_mount	*mp = dp->i_mount;



	if (xfs_sb_version_hascrc(&mp->m_sb)) {

		struct xfs_dir3_data_hdr *hdr3 = bp->b_addr;



		if (be64_to_cpu(hdr3->hdr.owner) != dp->i_ino)

			return __this_address;

	}



	return NULL;

}



int

xfs_dir3_data_read(
@@ -403,11 +419,23 @@ xfs_dir3_data_read( 
	unsigned int		flags,

	struct xfs_buf		**bpp)

{

	xfs_failaddr_t		fa;

	int			err;



	err = xfs_da_read_buf(tp, dp, bno, flags, bpp, XFS_DATA_FORK,

			&xfs_dir3_data_buf_ops);

	if (!err && tp && *bpp)

	if (err || !*bpp)

		return err;



	/* Check things that we can't do in the verifier. */

	fa = xfs_dir3_data_header_check(dp, *bpp);

	if (fa) {

		__xfs_buf_mark_corrupt(*bpp, fa);

		xfs_trans_brelse(tp, *bpp);

		*bpp = NULL;

		return -EFSCORRUPTED;

	}



	xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF);

	return err;

}