linux-kernel - Re: Controlling devices and device namespaces

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87pq5loqoa.fsf@xmission.com>
Date:	Sun, 16 Sep 2012 09:53:09 -0700
From:	ebiederm@...ssion.com (Eric W. Biederman)
To:	Serge Hallyn <serge@...lyn.com>
Cc:	Alan Cox <alan@...rguk.ukuu.org.uk>,
	Aristeu Rozanski <aris@...vo.org>,
	Neil Horman <nhorman@...driver.com>,
	containers@...ts.linux-foundation.org,
	linux-kernel@...r.kernel.org, Michal Hocko <mhocko@...e.cz>,
	Thomas Graf <tgraf@...g.ch>, Paul Mackerras <paulus@...ba.org>,
	"Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>,
	Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
	Johannes Weiner <hannes@...xchg.org>,
	Tejun Heo <tj@...nel.org>, cgroups@...r.kernel.org,
	Paul Turner <pjt@...gle.com>, Ingo Molnar <mingo@...hat.com>
Subject: Re: Controlling devices and device namespaces

Serge Hallyn <serge@...lyn.com> writes:

>>> That's what I said a few emails ago :)  The device cgroup was meant as
>>> a short-term workaround for lack of user (and device) namespaces.
>>
>> I am saying something stronger.  The device cgroup doesn't seem to have
>> a practical function now.
>
> "Now" is wrong.  The user namespace is not complete and not yet usable for a
> full system container.  We still need the device control group.

Dropping cap mknod, and not having any device nodes you can mount
a filesystem with device nodes, plus mount namespace work to only allow
you to have access to proper device nodes should work today.  And I
admit the user namespace as I have it coded in my tree does make this
simpler.

But I agree "Now" is too soon until we have actually demonstrated
something else.

Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/