Re: [PATCH 2/4] pid: Export find_task_by_vpid for use in external modules

Russell King - ARM Linux
2018-05-10T19:44:22Z

On Thu, May 10, 2018 at 01:39:18PM -0600, Mathieu Poirier wrote:
> Hi Russell,
>
> On 10 May 2018 at 02:40, Russell King - ARM Linux <linux@armlinux.org.uk> wrote:
> > This does not leak information from other namespaces because of the
> > uniqueness of the global PID. However, what it does leak is the value
> > of the global PID which is meaningless in the namespace. So, before
> > the event stream is delivered to userspace, this value needs to be
> > re-written to the namespace's PID value.
>
> Unfortunately that can't be done. The trace stream is compressed and
> needs to be decompressed using an external library. I think the only
> option is to return an error if a user is trying to use this feature
> from a namespace.

That sounds like a sensible approach, and that should get rid of the
vpid stuff too.

Eric, would this solve all your concerns?

--
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