Re: [PATCH v2 3/7] vhost: Add kthread support in function vhost_workers_free()

From: Cindy Lu
Date: Tue Oct 15 2024 - 02:06:36 EST


On Tue, 15 Oct 2024 at 05:06, Mike Christie <michael.christie@xxxxxxxxxx> wrote:
>
> On 10/3/24 8:58 PM, Cindy Lu wrote:
> > +static void vhost_workers_free(struct vhost_dev *dev)
> > +{
> > + if (enforce_inherit_owner)
> > + vhost_workers_free_task(dev);
> > + else
> > + vhost_workers_free_kthread(dev);
> > +}
>
> With patch 7, userspace could change enforce_inherit_owner after
> we created thread and we would call the wrong function above.
>
enforce_inherit_owner will only change before the owner was set.
the process is like set enforce_inherit_owner---->set owner->
thread/task creating
in in patch 7's code I have add the check for vhost's owner, if the
owner was set, the ioctl
to set enforce_inherit_owner will fail
Thanks
Cindy