The patch titled
Subject: mm/memcg: use struct_size() helper in kzalloc()
has been added to the -mm tree. Its filename is
mm-memcg-use-struct_size-helper-in-kzalloc.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-use-struct_size-helper-in-kzalloc.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-use-struct_size-helper-in-kzalloc.patch
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------------------------------------------------------
From: Wang Weiyang <wangweiyang2@xxxxxxxxxx>
Subject: 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@xxxxxxxxxx
Signed-off-by: Wang Weiyang <wangweiyang2@xxxxxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memcontrol.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
--- a/mm/memcontrol.c~mm-memcg-use-struct_size-helper-in-kzalloc
+++ a/mm/memcontrol.c
@@ -5122,15 +5122,11 @@ static void mem_cgroup_free(struct mem_c
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);
_
Patches currently in -mm which might be from wangweiyang2@xxxxxxxxxx are
mm-memcg-use-struct_size-helper-in-kzalloc.patch
