linux-kernel - Re: [RFC][PATCH 0/2] Another pass at Android style loosening of cgroup attach permissions

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: <CALAqxLVSuf556f_sz8t6BEczyO1xKtnqrmjyKy05hzAjggn3tw@mail.gmail.com>
Date:   Tue, 4 Oct 2016 11:03:43 -0700
From:   John Stultz <john.stultz@...aro.org>
To:     Tejun Heo <tj@...nel.org>
Cc:     lkml <linux-kernel@...r.kernel.org>, Li Zefan <lizefan@...wei.com>,
        Jonathan Corbet <corbet@....net>, cgroups@...r.kernel.org,
        Android Kernel Team <kernel-team@...roid.com>,
        Rom Lemarchand <romlem@...roid.com>,
        Colin Cross <ccross@...roid.com>,
        Dmitry Shmidt <dimitrysh@...gle.com>,
        Todd Kjos <tkjos@...gle.com>,
        Christian Poetzsch <christian.potzsch@...tec.com>,
        Amit Pundir <amit.pundir@...aro.org>
Subject: Re: [RFC][PATCH 0/2] Another pass at Android style loosening of
 cgroup attach permissions

On Tue, Oct 4, 2016 at 9:16 AM, Tejun Heo <tj@...nel.org> wrote:
> On Mon, Oct 03, 2016 at 09:41:28PM -0700, John Stultz wrote:
>> The migration of a task from the foreground to background, or to
>> elevate a task to audio priority, may be done by system service that
>> does not run as root. So this patch allows processes with CAP_SYS_NICE
>> to be able to migrate tasks between cgroups.  I suspect if there was a
>> specific cap (CAP_SYS_CHANGE_CGROUP) for this, it would be usable here,
>> but in its absence, they've overloaded CAP_SYS_NICE for this use.
>
> CAP_SYS_RESOURCE won't do?

Oh, and I'll have to look into this one to see what CAP_SYS_RESOURCE
actually allows. We ran into trouble in the past changing the CAPs
required to something higher-level, which then causes trouble because
they want to avoid elevating permissions on system tasks and keep them
as restricted as possible.

thans
-john