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

From: Tejun Heo
Date: Tue Oct 04 2016 - 16:33:42 EST


Hello, Serge.

On Tue, Oct 04, 2016 at 03:18:40PM -0500, Serge E. Hallyn wrote:
> how about changing the GLOBAL_ROOT_UID check with a targeted
> capability check, like
>
> if (!ns_capable(tcred->user_ns, CAP_SYS_NICE) &&
> !uid_eq(cred->euid, tcred->uid) &&
> !uid_eq(cred->euid, tcred->suid))
> ret = -EACCES;
>
> where the actual capability to use may require some thought.

Yeah, that's the direction I'm thinking too. We can't use
CAP_SYS_NICE in general tho. Let's see if a dedicated CAP sticks.

Thanks.

--
tejun