Commit 06b2c3b0 authored by Wang Weiyang's avatar Wang Weiyang Committed by Linus Torvalds
Browse files

mm/memcg: use struct_size() helper in kzalloc() 

Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worst scenario, could lead to heap overflows.

Link: https://github.com/KSPP/linux/issues/160
Link: https://lkml.kernel.org/r/20211216022024.127375-1-wangweiyang2@huawei.com


Signed-off-by: default avatarWang Weiyang <wangweiyang2@huawei.com>
Reviewed-by: default avatarMuchun Song <songmuchun@bytedance.com>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5b3be698

mm/memcontrol.c

+1 −5
Original line number Diff line number Diff line
@@ -5122,15 +5122,11 @@ static void mem_cgroup_free(struct mem_cgroup *memcg) 
static struct mem_cgroup *mem_cgroup_alloc(void)

{

	struct mem_cgroup *memcg;

	unsigned int size;

	int node;

	int __maybe_unused i;

	long error = -ENOMEM;



	size = sizeof(struct mem_cgroup);

	size += nr_node_ids * sizeof(struct mem_cgroup_per_node *);



	memcg = kzalloc(size, GFP_KERNEL);

	memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL);

	if (!memcg)

		return ERR_PTR(error);