Re: [PATCH 1/9] Known exploit detection

Ingo Molnar
2013-12-13T13:27:59Z

* Vegard Nossum <vegard.nossum@oracle.com> wrote:

> On 12/12/2013 10:13 PM, Kees Cook wrote:
>
> > I like it. I like how lightweight it is, and I like that it can be
> > trivially compiled out. My concerns would be:
> >
> > - how do we avoid bikeshedding about which exploits are "serious
> > enough" to trigger a report?
>
> Well, I've already suggested that only bugs that potentially lead to
> privilege escalation/intrusion (local and remote) would be
> candidates. This probably includes any kind of buffer overflow or
> "wild write" bug.

It's also up to the maintainer of the subsystem, so bikeshedding is
only as effective as the maintainer allows it to be.

> Clearly, a bug should also be present over a complete release cycle
> before it's worth annotating. [...]

Yes, only bugs present in a released kernel are candiates.

> [...] A bug introduced in -rc1 and fixed in -rc5 is NOT a candidate.

That's generally true, except perhaps in the special case if a bug got
backported and released in a stable kernel, and some good exploit got
released for that bug. In that case checking it is useful.

The point is that we want to check things that have a chance to result
in actual messages: i.e. deterministically triggerable bugs in
released kernel that are either trivially exploitable or are known to
be exploited in exploit kits.

Thanks,

Ingo