Re: [PATCH] fork: do not release lock that wasn't taken

From: Christian Brauner
Date: Fri May 10 2019 - 15:29:54 EST


On Fri, May 10, 2019 at 05:36:47PM +0200, Oleg Nesterov wrote:
> On 05/10, Christian Brauner wrote:
> >
> > @@ -2102,7 +2102,7 @@ static __latent_entropy struct task_struct *copy_process(
> > */
> > retval = cgroup_can_fork(p);
> > if (retval)
> > - goto bad_fork_put_pidfd;
> > + goto bad_fork_cgroup_threadgroup_change_end;
> >
> > /*
> > * From this point on we must avoid any synchronous user-space
> > @@ -2217,11 +2217,12 @@ static __latent_entropy struct task_struct *copy_process(
> > spin_unlock(&current->sighand->siglock);
> > write_unlock_irq(&tasklist_lock);
> > cgroup_cancel_fork(p);
> > +bad_fork_cgroup_threadgroup_change_end:
> > + cgroup_threadgroup_change_end(current);
> > bad_fork_put_pidfd:
> > if (clone_flags & CLONE_PIDFD)
> > ksys_close(pidfd);
> > bad_fork_free_pid:
> > - cgroup_threadgroup_change_end(current);
> > if (pid != &init_struct_pid)
> > free_pid(pid);
> > bad_fork_cleanup_thread:
>
> Reviewed-by: Oleg Nesterov <oleg@xxxxxxxxxx>

Thanks for the quick review, Oleg! :)
Christian