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From: Arnd Bergmann <arnd@arndb.de>
To: "John Stoffel" <john@stoffel.org>
Subject: Re: chroot(2) and bind mounts as non-root
Date: Thu, 8 Dec 2011 17:04:22 +0000
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Cc: Colin Walters <walters@verbum.org>, LKML <linux-kernel@vger.kernel.org>,
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On Wednesday 07 December 2011, John Stoffel wrote:
> >>>>> "Colin" == Colin Walters <walters@verbum.org> writes:
> 
> Colin> I've recently been doing some work in software compilation, and it'd be
> Colin> really handy if I could call chroot(2) as a non-root user.  The reason
> Colin> to chroot is to help avoid "host contamination" - I can set up a build
> Colin> root and then chroot in.  The reason to do it as non-root is, well,
> Colin> requiring root to build software sucks for multiple obvious reasons.
> 
> What's wrong with using 'fakeroot' or tools like that instead?  Why
> does the Kernel need to be involved like this?  I'm not against your
> proposal so much, as trying to understand how compiling a bunch of
> source requires this change.

I think the better question to ask is what is missing from 'schroot', which
is commonly used for exactly this purpose. Is it just about avoing the
suid bit for /usr/bin/schroot or something else?

	Arnd