[PATCH v3 5/7] mm: kmemleak: use mem_pool_free() to free object

From: Liu Shixin
Date: Wed Oct 18 2023 - 05:30:54 EST


The kmemleak object is allocated by mem_pool_alloc(), which
could be from slab or mem_pool[], so it's not suitable using
__kmem_cache_free() to free the object, use __mem_pool_free()
instead.

Fixes: 0647398a8c7b ("mm: kmemleak: simple memory allocation pool for kmemleak objects")
Signed-off-by: Liu Shixin <liushixin2@xxxxxxxxxx>
---
mm/kmemleak.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 064fc3695c6b..ea34986c02b4 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -668,8 +668,8 @@ static struct kmemleak_object * __alloc_object(gfp_t gfp)
return object;
}

-static void __link_object(struct kmemleak_object *object, unsigned long ptr,
- size_t size, int min_count, bool is_phys)
+static int __link_object(struct kmemleak_object *object, unsigned long ptr,
+ size_t size, int min_count, bool is_phys)
{

struct kmemleak_object *parent;
@@ -711,14 +711,15 @@ static void __link_object(struct kmemleak_object *object, unsigned long ptr,
* be freed while the kmemleak_lock is held.
*/
dump_object_info(parent);
- kmem_cache_free(object_cache, object);
- return;
+ return -EEXIST;
}
}
rb_link_node(&object->rb_node, rb_parent, link);
rb_insert_color(&object->rb_node, is_phys ? &object_phys_tree_root :
&object_tree_root);
list_add_tail_rcu(&object->object_list, &object_list);
+
+ return 0;
}

/*
@@ -731,14 +732,17 @@ static void __create_object(unsigned long ptr, size_t size,
{
struct kmemleak_object *object;
unsigned long flags;
+ int ret;

object = __alloc_object(gfp);
if (!object)
return;

raw_spin_lock_irqsave(&kmemleak_lock, flags);
- __link_object(object, ptr, size, min_count, is_phys);
+ ret = __link_object(object, ptr, size, min_count, is_phys);
raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
+ if (ret)
+ mem_pool_free(object);
}

/* Create kmemleak object which allocated with virtual address. */
--
2.25.1