Re: cgroup user-after-free

From: tj@xxxxxxxxxx
Date: Thu Jan 12 2023 - 20:14:39 EST


On Thu, Jan 12, 2023 at 09:48:55AM +0000, Lixiong Liu (刘利雄) wrote:
> Hi,
>
> We meet cgroup use-after-free happened in T SW version with
>
> kernel-5.15.
>
> Root cause:
> cgroup_migrate_finish free cset’s cgroup,
>
> but cgroup_sk_alloc use the freed cgroup,
>
> then use-after-free happened.

Sounds similar to the problem fixed by 07fd5b6cdf3c ("cgroup: Use separate
src/dst nodes when preloading css_sets for migration"). Can you try it out?

Thanks.

--
tejun