Messages in this thread | | | Date | Fri, 28 Sep 2018 10:23:40 -0700 | From | Andi Kleen <> | Subject | Re: [RFC 0/5] perf: Per PMU access controls (paranoid setting) |
| |
> There's also been prior discussion on these feature in other contexts > (e.g. android expoits resulting from out-of-tree drivers). It would be > nice to see those considered. > > IIRC The conclusion from prior discussions (e.g. [1]) was that we wanted > finer granularity of control such that we could limit PMU access to > specific users -- e.g. disallow arbitrary android apps from poking *any* > PMU, while allowing some more trusted apps/users to uses *some* specific > PMUs. > > e.g. we could add /sys/bus/event_source/devices/${PMU}/device, protect > this via the usual fs ACLs, and pass the fd to perf_event_open() > somehow. A valid fd would act as a capability, taking precedence over > perf_event_paranoid.
That sounds like an orthogonal feature. I don't think the original patchkit would need to be hold up for this. It would be something in addition.
BTW can't you already do that with the syscall filter? I assume the Android sandboxes already use that. Just forbid perf_event_open for the apps.
-Andi
| |