Re: [PATCH] xfs: dabtree scrub needs to range-check level

[Brian Foster <bfoster@redhat.com>]

On Mon, Mar 18, 2019 at 09:42:15AM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Make sure scrub's dabtree iterator function checks that we're not
> going deeper in the stack than our cursor permits.  Found by sparse.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

>  fs/xfs/scrub/dabtree.c |    5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/fs/xfs/scrub/dabtree.c b/fs/xfs/scrub/dabtree.c
> index c6ab123b6051..5c6175d074e0 100644
> --- a/fs/xfs/scrub/dabtree.c
> +++ b/fs/xfs/scrub/dabtree.c
> @@ -604,6 +604,11 @@ xchk_da_btree(
>  		/* Drill another level deeper. */
>  		blkno = be32_to_cpu(key->before);
>  		level++;
> +		if (level >= XFS_DA_NODE_MAXDEPTH) {
> +			/* Too deep! */
> +			xchk_da_set_corrupt(&ds, level - 1);
> +			break;
> +		}
>  		ds.tree_level--;
>  		error = xchk_da_btree_block(&ds, level, blkno);
>  		if (error)