Re: [kernel-hardening] Re: [PATCH 1/2] security, perf: allow further restriction of perf_event_open

[Peter Zijlstra]

On Wed, Aug 03, 2016 at 11:53:41AM -0700, Kees Cook wrote:
> > Kees Cook <keescook@xxxxxxxxxxxx> writes:
> >
> >> On Tue, Aug 2, 2016 at 1:30 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >> Let me take this another way instead. What would be a better way to
> >> provide a mechanism for system owners to disable perf without an LSM?
> >> (Since far fewer folks run with an enforcing "big" LSM: I'm seeking as
> >> wide a coverage as possible.)
> >
> > I vote for sandboxes.  Perhaps seccomp.  Perhaps a per userns sysctl.
> > Perhaps something else.
> 
> Peter, did you happen to see Eric's solution to this problem for
> namespaces? Basically, a per-userns sysctl instead of a global sysctl.
> Is that something that would be acceptable here?

Someone would have to educate me on what a userns is and how that would
help here.