Re: [PATCH] cgroup1: fix leaked context root causing sporadic NULL deref in LTP

[Tejun Heo]

Hello,

On Wed, Jun 16, 2021 at 08:51:57AM -0400, Paul Gortmaker wrote:
> A fix would be to not leave the stale reference in fc->root as follows:
> 
>    --------------
>                   dput(fc->root);
>   +               fc->root = NULL;
>                   deactivate_locked_super(sb);
>    --------------
> 
> ...but then we are just open-coding a duplicate of fc_drop_locked() so we
> simply use that instead.

As this is unlikely to be a real-world problem both in probability and
circumstances, I'm applying this to cgroup/for-5.14 instead of
cgroup/for-5.13-fixes.

Thanks.

-- 
tejun