linux-kernel - Re: [RFC v2 00/10] Landlock LSM: Unprivileged sandboxing (cgroup delegation)

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: <57C1B003.1030608@digikod.net>
Date:   Sat, 27 Aug 2016 17:21:39 +0200
From:   Mickaël Salaün <mic@...ikod.net>
To:     Mickaël Salaün <mic@...ikod.net>,
        Andy Lutomirski <luto@...capital.net>
Cc:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Alexei Starovoitov <ast@...nel.org>,
        Arnd Bergmann <arnd@...db.de>,
        Casey Schaufler <casey@...aufler-ca.com>,
        Daniel Borkmann <daniel@...earbox.net>,
        Daniel Mack <daniel@...que.org>,
        David Drysdale <drysdale@...gle.com>,
        "David S . Miller" <davem@...emloft.net>,
        Elena Reshetova <elena.reshetova@...el.com>,
        James Morris <james.l.morris@...cle.com>,
        Kees Cook <keescook@...omium.org>,
        Paul Moore <pmoore@...hat.com>,
        Sargun Dhillon <sargun@...gun.me>,
        "Serge E . Hallyn" <serge@...lyn.com>,
        Will Drewry <wad@...omium.org>,
        Kernel Hardening <kernel-hardening@...ts.openwall.com>,
        Linux API <linux-api@...r.kernel.org>,
        LSM List <linux-security-module@...r.kernel.org>,
        Network Development <netdev@...r.kernel.org>,
        Tejun Heo <tj@...nel.org>, cgroups@...r.kernel.org
Subject: Re: [RFC v2 00/10] Landlock LSM: Unprivileged sandboxing (cgroup
 delegation)

Cc Tejun and the cgroups ML.

On 27/08/2016 17:10, Mickaël Salaün wrote:
> On 27/08/2016 09:40, Andy Lutomirski wrote:
>> On Thu, Aug 25, 2016 at 3:32 AM, Mickaël Salaün <mic@...ikod.net> wrote:
>>>
>>> # Sandbox example with conditional access control depending on cgroup
>>>
>>>   $ mkdir /sys/fs/cgroup/sandboxed
>>>   $ ls /home
>>>   user1
>>>   $ LANDLOCK_CGROUPS='/sys/fs/cgroup/sandboxed' \
>>>       LANDLOCK_ALLOWED='/bin:/lib:/usr:/tmp:/proc/self/fd/0' \
>>>       ./sandbox /bin/sh -i
>>>   $ ls /home
>>>   user1
>>>   $ echo $$ > /sys/fs/cgroup/sandboxed/cgroup.procs
>>>   $ ls /home
>>>   ls: cannot open directory '/home': Permission denied
>>>
>>
>> Something occurs to me that isn't strictly relevant to landlock but
>> may be relevant to unprivileged cgroups: can you cause trouble by
>> setting up a nastily-configured cgroup and running a setuid program in
>> it?
>>
> 
> I hope not… But the use of cgroups should not be mandatory for Landlock.
> 

In a previous email:

On 26/08/2016 17:50, Tejun Heo wrote:
> I haven't looked in detail but in general I'm not too excited about
> layering security mechanism on top of cgroup.  Maybe it makes some
> sense when security domain coincides with resource domains but at any
> rate please keep me in the loop.




Download attachment "signature.asc" of type "application/pgp-signature" (456 bytes)