Commit 33af39d0 authored by Peng Zhang's avatar Peng Zhang Committed by Andrew Morton
Browse files

maple_tree: make mas_validate_limits() check root node and node limit 

Update mas_validate_limits() to check root node, check node limit pivot if
there is enough room for it to exist and check data_end.  Remove the check
for child existence as it is done in mas_validate_child_slot().

Link: https://lkml.kernel.org/r/20230711035444.526-6-zhangpeng.00@bytedance.com


Signed-off-by: default avatarPeng Zhang <zhangpeng.00@bytedance.com>
Tested-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent e93fda5a

lib/maple_tree.c

+14 −16
Original line number Diff line number Diff line
@@ -7120,7 +7120,9 @@ static void mas_validate_child_slot(struct ma_state *mas) 
}



/*

 * Validate all pivots are within mas->min and mas->max.

 * Validate all pivots are within mas->min and mas->max, check metadata ends

 * where the maximum ends and ensure there is no slots or pivots set outside of

 * the end of the data.

 */

static void mas_validate_limits(struct ma_state *mas)

{
@@ -7130,26 +7132,15 @@ static void mas_validate_limits(struct ma_state *mas) 
	void __rcu **slots = ma_slots(mte_to_node(mas->node), type);

	unsigned long *pivots = ma_pivots(mas_mn(mas), type);



	/* all limits are fine here. */

	if (mte_is_root(mas->node))

		return;



	for (i = 0; i < mt_slots[type]; i++) {

		unsigned long piv;



		piv = mas_safe_pivot(mas, pivots, i, type);



		if (!piv && (i != 0))

			break;



		if (!mte_is_leaf(mas->node)) {

			void *entry = mas_slot(mas, slots, i);



			if (!entry)

				pr_err("%p[%u] cannot be null\n",

		if (!piv && (i != 0)) {

			pr_err("Missing node limit pivot at %p[%u]",

			       mas_mn(mas), i);



			MT_BUG_ON(mas->tree, !entry);

			MAS_WARN_ON(mas, 1);

		}



		if (prev_piv > piv) {
@@ -7172,6 +7163,13 @@ static void mas_validate_limits(struct ma_state *mas) 
		if (piv == mas->max)

			break;

	}



	if (mas_data_end(mas) != i) {

		pr_err("node%p: data_end %u != the last slot offset %u\n",

		       mas_mn(mas), mas_data_end(mas), i);

		MT_BUG_ON(mas->tree, 1);

	}



	for (i += 1; i < mt_slots[type]; i++) {

		void *entry = mas_slot(mas, slots, i);