Re: [RESEND PATCH 4/8] maple_tree: fix mas_validate_child_slot() to check last missed slot

From: Liam R. Howlett
Date: Fri Jul 07 2023 - 11:20:01 EST


* Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx> [230707 06:11]:
> Don't break the loop before checking the last slot. Also here check if
> non-leaf nodes are missing children.
>
> Signed-off-by: Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx>

Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>

> ---
> lib/maple_tree.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 1fe8b6a787dd..88d6373f37b0 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -7111,11 +7111,12 @@ static void mas_validate_child_slot(struct ma_state *mas)
>
> for (i = 0; i < mt_slots[type]; i++) {
> child = mas_slot(mas, slots, i);
> - if (!pivots[i] || pivots[i] == mas->max)
> - break;
>
> - if (!child)
> - break;
> + if (!child) {
> + pr_err("Non-leaf node lacks child at %p[%u]\n",
> + mas_mn(mas), i);
> + MT_BUG_ON(mas->tree, 1);
> + }
>
> if (mte_parent_slot(child) != i) {
> pr_err("Slot error at %p[%u]: child %p has pslot %u\n",
> @@ -7130,6 +7131,9 @@ static void mas_validate_child_slot(struct ma_state *mas)
> mte_to_node(mas->node));
> MT_BUG_ON(mas->tree, 1);
> }
> +
> + if (i < mt_pivots[type] && pivots[i] == mas->max)
> + break;
> }
> }
>
> --
> 2.20.1
>
>