Re: [PATCH v10 09/12] arch/x86: enable task isolation functionality

From: Andy Lutomirski
Date: Wed Mar 09 2016 - 16:08:27 EST

On Wed, Mar 9, 2016 at 1:05 PM, Chris Metcalf <cmetcalf@xxxxxxxxxxxx> wrote:
> On 3/9/2016 3:58 PM, Andy Lutomirski wrote:
>>> My preference would be not to have to require all task-isolation users
>>> >to also figure out all the complexities of creating BPF programs, so
>>> >my intention is to have task isolation automatically generate a BPF
>>> >program (just allowing prctl/exit/exit_group and failing everything
>>> >else with SIGSYS). To support having it work this way, I open up
>>> >the seccomp stuff a little so that kernel clients can effectively
>>> >push/pop a BPF program into seccomp:
>> That sounds like a great use case for the new libtaskisolation that
>> someone is surely writing:)
> Happily, task isolation is so simple an API that all that is needed is a
> prctl().
> ... Unless somehow a requirement to inflict a huge blob of eBPF into the
> kernel
> just to use task isolation safely is added, of course :-)

BPF, not eBPF. Also, it's a tiny blob.

And this still has nothing to do with using it safely. This has to do
with catching your own bugs.


> --
> Chris Metcalf, Mellanox Technologies

Andy Lutomirski
AMA Capital Management, LLC