From: Al Boldi <a1426z@gawab.com>
Subject: Re: [PATCH 12/18] shared mount handling: bind and rbind
Date: Wed, 16 Nov 2005 08:35:28 +0300
Message-ID: <200511160835.28636.a1426z@gawab.com>
References: <E1EZInj-0001Ez-AV@ZenIV.linux.org.uk> <200511152129.04079.rob@landley.net> <Pine.LNX.4.64.0511151948570.13959@g5.osdl.org>
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Cc: Ram Pai <linuxram@us.ibm.com>, Miklos Szeredi <miklos@szeredi.hu>,
	Al Viro <viro@ftp.linux.org.uk>, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, Rob Landley <rob@landley.net>
Return-path: <linux-kernel-owner+glk-linux-kernel-3=40m.gmane.org-S932590AbVKPFo2@vger.kernel.org>
To: Linus Torvalds <torvalds@osdl.org>
In-Reply-To: <Pine.LNX.4.64.0511151948570.13959@g5.osdl.org>
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Linus Torvalds wrote:
> This is why we have "pivot_root()" and "chroot()", which can both be used
> to do what you want to do. You mount the new root somewhere else, and then
> you chroot (or pivot-root) to it. And THEN you do 'chdir("/")' to move the
> cwd into the new root too (and only at that point have you "lost" the old
> root - although you can actually get it back if you have some file
> descriptor open to it).

Wouldn't this constitute a security flaw?

Shouldn't chroot jail you?

--
Al