Re: OS stopping stack buffer overflow exploits

Ingo Oeser (ingo.oeser@informatik.tu-chemnitz.de)
Sun, 4 Jun 2000 12:06:10 +0200

On Sun, Jun 04, 2000 at 05:07:35AM -0400, Jeff Garzik wrote:
> > Could you please show a daily example of any *need* for
> > trampolines? I mean code, which could only be implemented
> > (efficiently) via trampolines.
> >
> > I never saw one generated by GCC and never wrote an explicit one
> > by myself. So for what important piece of code we do need it and
> > can't code it without trampolines?
>
> A commercial Java compiler (the fastest one on the market AFAIK) uses
> then, and IIRC Gnu Ada uses some features which are unfriendly to the
> OS attempting to stop stack overflow exploits across the board.

No code shown either. And no reason deployed, why we couldn't
code this without trampolines in the old threads.

> In any case, this thread has been beaten to death. Maybe we should all
> just re-read the old threads? :)

I've followed these threads and got no answer. I only saw
comments like "it is _really_ needed, because XXX uses it." But
never saw _any_ code, which will perform much worse without them.

I only know, that there exists code, which uses it, but never
been able to understand the reasoning behind doing it that way.

So I still wait for a beating performance argument (factor or
order of magnitude) ;-)

Thanks and Regards

Ingo Oeser

-- 
Feel the power of the penguin - run linux@your.pc
<esc>:x


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