Re: linux 5.14.3: free_user_ns causes NULL pointer dereference

[Alexey Gladkov]

On Wed, Sep 29, 2021 at 09:39:06PM +0000, Jordan Glover wrote:
> > I'm still investigating, but I would like to rule out one option.
> >
> > Could you check out the patch?
> 
> 
> Thx, I added it to my kernel and will report in few days.
> Does this patch try to fix the issue or make it easier to track?

I suspect the error is caused by a race between allow_ucounts() and
put_ucounts(). I think this patch could solve the problem.

-- 
Rgrds, legion