Re: Linux 2.2.18pre21

[R.E.Wolff@BitWizard.nl (Rogier Wolff)]

Alan Cox wrote:
> > It's simply not good enough to close all directory file descriptors before chrooting.
> > 
> > If calling chroot once you're already in a chroot jail was disallowed, it would stop
> > this attack.
 
> I think the problem here is that some people have the idea that
> chroot is some kind of magical security device. Thats not true at
> all. You can build an environment like that if you wish by closing
> other directory handles and having no suitably priviledged code in
> the chroot area and stuff.

I read about the BSD Jail stuff a while ago. 

It's a nice "operating system class lab project". Estimated time
needed: 40 hours.

This IS the magical security device. 

				Roger. 
-- 
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