Re: [PATCH] leaking_addresses: Provide mechanism to scan binary files

Kees Cook
2024-02-29T05:30:09Z

On Thu, Feb 29, 2024 at 03:40:13PM +1100, Tobin Harding wrote:
> On Thu, Feb 22, 2024 at 04:49:26PM -0700, Tycho Andersen wrote:
> > On Thu, Feb 22, 2024 at 01:00:40PM -0800, Kees Cook wrote:
> > > > This does bring up some interesting questions. From off-list
> > > > discussions with Tobin, I believe he is not particularly interested in
> > > > maintaining this script any more. I was never set up to do the PRs
> > > > myself, I agreed to be a reviewer to help Tobin out. I'm happy to
> > > > adopt it if that makes sense, but I'm curious about the future of the
> > > > script:
> > > >
> > > > 1. is it useful? (seems like yes if you're adding features)
> > >
> > > Yes, LKP runs it as part of 0-day, and it's found leaks in the past[1].
> > > (Though its usage could be improved.)
> >
> > Oh! That is good news :)
> >
> > > > 2. does it make sense to live here as a separate thing? should we
> > > > perhaps run it as part of kselftests or similar? I think that e.g.
> > > > 681ff0181bbf ("x86/mm/init/32: Stop printing the virtual memory
> > > > layout") was not discovered with this script, but maybe if we put it
> > > > inline with some other stuff people regularly run more of these would
> > > > fall out? Maybe it makes sense to live somewhere else entirely
> > > > (syzkaller)? I can probably set up some x86/arm64 infra to run it
> > > > regularly, but that won't catch other less popular arches.
> > >
> > > We could certainly do that. It would need some work to clean it up,
> > > though -- it seems like it wasn't designed to run as root (which is how
> > > LKP runs it, and likely how at least some CIs would run it).
> > >
> > > > 3. perl. I'm mostly not a perl programmer, but would be happy to
> > > > rewrite it in python pending the outcome of discussion above.
> > >
> > > I am not a Perl fan either. It does work as-is, though. Address leaks,
> > > while worth fixing, are relatively low priority over all, so I wouldn't
> > > prioritize a rewrite very highly.
> >
> > Yep, fair enough.
>
> Thanks for taking this in through your tree Kees! And Tycho for
> picking up the pieces I dropped :)

Hi! You're welcome; I'm glad I have this script to build on!

> I can help review a re-write if it helps though I don't write Python
> daily and I am long way away from kernel work these days so I doubt
> I'd be all that much help.

No worries. I suppose we could rewrite it in Rust! :)

> I originally wrote it in Perl because I figured it would be easier to
> get past the old guys, six moths later I regretted the decision when I
> tried to re-read it.
>
> Thanks for ping'ing me.

Good to hear from you!

Take care,

-Kees

--
Kees Cook