[1013] in athena10
Re: Failsafe xterm and breaking out of the chroot
daemon@ATHENA.MIT.EDU (Aaron M. Ucko)
Tue Jan 27 20:59:22 2009
To: Anders Kaseorg <andersk@mit.edu>
Cc: "Aaron M. Ucko" <ucko@debian.org>, Evan Broder <broder@mit.edu>,
debathena@mit.edu
From: amu@alum.MIT.EDU (Aaron M. Ucko)
Date: Tue, 27 Jan 2009 20:57:59 -0500
In-Reply-To: <alpine.DEB.2.00.0901272039480.27161@vinegar-pot.mit.edu> (Anders Kaseorg's message of "Tue, 27 Jan 2009 20:40:11 -0500 (EST)")
Message-ID: <udlpri8kx94.fsf@vinegar-pot.mit.edu>
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Anders Kaseorg <andersk@MIT.EDU> writes:
> On Tue, 27 Jan 2009, Anders Kaseorg wrote:
>> /proc/1/root is just a symlink; it points to the path (/), not the
>> actual inode. You canÕt break out of a chroot with a symlink.
>
> Or maybe I spoke too soon, because this does actually appear to
> ÒworkÓ. Special.
Yeah, there's some magic involved; udev's postinst passively exploits
the same trick to determine whether it's in a chroot (in which case it
simply bails, of course).
--
Aaron M. Ucko, KB1CJC (amu at alum.mit.edu, ucko at debian.org)
http://www.mit.edu/~amu/ | http://stuff.mit.edu/cgi/finger/?amu@monk.mit.edu
