Re: [PATCH 4/4] Allow unprivileged chroot when safe

From: Andy Lutomirski
Date: Mon Jan 16 2012 - 15:18:59 EST


On Mon, Jan 16, 2012 at 11:26 AM, Colin Walters <walters@xxxxxxxxxx> wrote:
> On Sun, 2012-01-15 at 16:37 -0800, Andy Lutomirski wrote:
>
>> Because chroot is an easy way to break out of chroot jail, CAP_SYS_ADMIN
>> is still required if the caller is already chrooted.
>
> This part is pretty gross.  It means it won't work for stuff like
> containers (systemd-nspawn etc.) and furthermore I have plans that
> involve running OS trees inside a chroot, and this would obviously not
> work for that.

Agreed.

Unprivileged bind mounts would be a much better approach, but that
would need some concept of an unprivileged user owning a namespace.
Maybe the namespace id work would make this work.

--Andy
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