From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: [WTF] ... is going on with current->fs->{root,mnt} accesses in
 pohmelfs
Date: Wed, 10 Feb 2010 10:04:28 +0000
Message-ID: <20100210100428.GL30031@ZenIV.linux.org.uk>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
To: zbr@ioremap.net
Return-path: <linux-kernel-owner@vger.kernel.org>
Content-Disposition: inline
Sender: linux-kernel-owner@vger.kernel.org
List-Id: linux-fsdevel.vger.kernel.org

a) pohmelfs_construct_path_string() will do interesting things if you
call it while chrooted into jail and pohmelfs mounted deeper in that
jail.  Try it.

b) just why do we care about root of chroot jail in pohmelfs_path_length()?
Not to mention anything else, current->fs->root/mnt may be changed under
you if you share current->fs with another thread, but even aside of that,
why does filesystem care about chroot of caller at all?

What's going on there?