Re: [PATCH 2/3] Security: Implement disablenetwork semantics. (v4)

[Pavel Machek]

> Quoting Michael Stone (michael@xxxxxxxxxx):
> > Serge Hallyn wrote:
> > >Michael, I'm sorry, I should go back and search the thread for the
> > >answer, but don't have time right now - do you really need
> > >disablenetwork to be available to unprivileged users?
> > 
> > Rainbow can only drop the networking privileges when we know at app launch time
> > (e.g. based on a manifest or from the human operator) that privileges can be
> > dropped. Unfortunately, most of the really interesting uses of disablenetwork
> > happen *after* rainbow has dropped privilege and handed control the app.
> > Therefore, having an API which can be used by at least some low-privilege
> > processes is important to me.
> > 
> > >is it ok to require CAP_SETPCAP (same thing required for dropping privs from
> > >bounding set)?
> > 
> > Let me try to restate your idea:
> > 
> >   We can make disablenetwork safer by permitting its use only where explicitly
> >   permitted by some previously privileged ancestor. The securebits facility
> >   described in
> > 
> >     http://lwn.net/Articles/280279/
> > 
> >   may be a good framework in which to implement this control.
> > 
> > Did I understand correctly? If so, then yes, this approach seems like it would
> > work for me.
> 
> That is a little more than I was saying this time though I think I
> suggested it earlier.
> 
> But really I don't think anyone would care to separate a system into
> some processes allowed to do unprivileged disablenetwork and other
> processes not allowed to, so a (root-owned mode 644) sysctl seems just
> as useful.

Global solution like that is always wrong. (And we have better
solution available.)
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/