Re: 2.6.25-mm1: not looking good

[Ingo Molnar <mingo@elte.hu>]

* Andrew Morton <akpm@linux-foundation.org> wrote:

> On Thu, 17 Apr 2008 22:49:08 -0700 Arjan van de Ven <arjan@infradead.org> wrote:
> 
> > On Thu, 17 Apr 2008 16:03:31 -0700
> > Andrew Morton <akpm@linux-foundation.org> wrote:
> > 
> > > 
> > > I repulled all the trees an hour or two ago, installed everything on
> > > an 8-way x86_64 box and:
> > > 
> > > 
> > > stack-protector:
> > > 
> > > Testing -fstack-protector-all feature
> > > No -fstack-protector-stack-frame!
> > > -fstack-protector-all test failed
> > 
> > do you have a stack-protector capable GCC? I guess not.
> > 
> > This is a catch-22. You do not have stack-protector. Should we make that 
> > a silent failure? or do you want to know that you don't have a security
> > feature you thought you had.... complaining seems to be the right thing to do imo.
> 
> A #warning sounds more appropriate.

this warning is telling the user that the security feature that got 
enabled in the .config is completely, 100% not working due to using a
stack-protector-incapable GCC.

it's analogous as if there was a bug in gcc that made SELinux totally 
ineffective in some mitigate-exploit-damage scenarios. No harm done on a 
perfectly bug-free system - but once a bug happens that SELinux should 
have mitigated, the breakage becomes real. Having a prominent warning is 
the _minimum_.

having a build failure would be nice too because this is a build 
environment problem. (not a build warning - warnings can easily be 
missed because on a typical kernel build there's so many false positives 
that get emitted by various other warning mechanisms) Arjan?

	Ingo