Following is the next version of the user namespace patchset. The core of the set is patch 2, originally conceived of and implemented by Eric Biederman. The concept is to target capabilities at user namespaces. A task's capabilities are now contextualized as follows (previously, capabilities had no context): 1. For a task in the initial user namespace, the calculated capabilities (pi, pe, pp) are available to act upon any user namespace. 2. For a task in a child user namespace, the calculated capabilities are available to act only on its own or any descendent user namespace. It has no capabilities to any parent or unrelated user namespaces. 3. If a user A creates a new user namespace, that user has all capabilities to that new user namespace and any of its descendents. (Contrast this with a user namespace created by another user B in the same user namespace, to which this user A has only his calculated capabilities) All existing 'capable' checks are automatically converted to checks against the initial user namespace. This means that by default, root in a child user namespace is powerless. Patches 3-5 begin to enable capabilities in child user namespaces to set hostnames, kill tasks, and do ptrace. My near-term next goals will be to enable setuid and setgid, and to provide a way for the filesystem to be usable in child user namespaces. At the very least I'd like a fresh loopback or LVM mount and proc mounts to be supported. thanks, -serge _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
