maple_tree: fix mas_validate_child_slot() to check last missed slot

Don't break the loop before checking the last slot.  Also here check if
non-leaf nodes are missing children.

Link: https://lkml.kernel.org/r/20230711035444.526-5-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 9ce78e5e608403d599fc2d7333d648df9a731e93..af8fb75ad68866b6c9e827225d2b9f4e36112086 100644 (file)
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -7093,11 +7093,12 @@ 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",
@@ -7112,6 +7113,9 @@ 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;
        }
 }