[PATCH 4/7] allow killing tasks in your own or child userns

Bastian Blank bastian at waldi.eu.org
Sat Jan 15 03:30:25 PST 2011

On Sat, Jan 15, 2011 at 12:31:14AM +0000, Serge E. Hallyn wrote:
> Quoting Bastian Blank (bastian at waldi.eu.org):
> > On Tue, Jan 11, 2011 at 01:31:52AM +0000, Serge E. Hallyn wrote:
> > > Quoting Bastian Blank (bastian at waldi.eu.org):
> > > > What is this flag used for anyway? I only see it used in the accounting
> > > > stuff, and if every user can get it, it is not longer useful.
> > > hm, I'm not sure...  maybe noone is using it!
> > However with your patches (or at least the goal), everyone is super-user
> > in derived namespaces.
> No, a task just sitting in a derived ns won't necessarily need/use
> super-user privileges...  (and, if we ever get far enough along, it
> won't even necessarily have CAP_SYS_ADMIN/etc targeted to the parent
> userns, bc it won't need those to do the unshares).

The goal, as I understand it, is that everyone can create derived user
namespaces. However the creator have automatically all the capabilities
in the derived namespace. So he can use them to gain this super-user
flag. Even killing a tasks in the derived namespace needs the capability


Those who hate and fight must stop themselves -- otherwise it is not stopped.
		-- Spock, "Day of the Dove", stardate unknown

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