[PATCH v2 4/8] maple_tree: fix mas_validate_child_slot() to check last missed slot

[Peng Zhang <zhangpeng.00@bytedance.com>]

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@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 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 a5776fab1875..f750ebef595f 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -7119,11 +7119,12 @@ 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",
@@ -7138,6 +7139,9 @@ 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