On Tue, 2015-03-31 at 09:57 +0200, Alexander Larsson wrote: > On fre, 2015-03-27 at 10:03 +0100, James Bottomley > > > > > On Fri, Feb 20, 2015 at 5:04 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: > > > > It's currently impossible to mount devpts in a user namespace that > > > > has no root user, since ptmx can't be created. > > > > This is where I stopped reading because it's not true ... because it is > > possible, you just do it from the host as real root. > > The point is being able to set up a container as a user, not requiring > the setup to be run as root at all. In my case container is a desktop > application which will be started by the user, and will run as the user. > There is no root involved in the call chain at all. I don't really like that use case: Most container setups are under the control of an orchestration system (like LXC, OpenVZ or even Docker). You typically get the orchestration system to do the dangerous operations (mount being one of the bigger dangers) because it has the capacity to vet them. I can see the value in allowing a user to set up a container without an oversight system, but at the same time you're increasing the security vulnerability of the system. Security is often a result of policy, so now this embeds policy into the kernel. I strongly feel we should define the list of things we expect an unsupervised (as in with no orchestration system) container to do and then revisit this once we've given it some thought. James -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
