From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Subject: Re: [PATCH 0/3] keys: play nicely with user namespaces Date: Fri, 12 Dec 2008 12:51:34 +0000 Message-ID: <3507.1229086294@redhat.com> References: <20081211232323.GA8343@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20081211232323.GA8343-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Serge E. Hallyn" Cc: dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Linux Containers , "Eric W. Biederman" List-Id: containers.vger.kernel.org Serge E. Hallyn wrote: > so here is a first attempt at getting keys and uid namespaces > to play nice. The semantics need some discussion. As I recall > Eric and yourself appeared to agree that some keyrings should > be inherited into child user namespaces. Ummm... If keys are effectively a per-user-namespace resource, then they can't be shared between namespaces. We could either duplicate all the keys and keyrings, or we could just start afresh. The latter is certainly the easiest. > I segragate them cleanly bc that appears to be the simplest thing to do > especially given the use of i.e. lookup_by_name("uid.500"). Sounds reasonable. > IMO it shouldn't be a big problem - userspace can always list keys it wants > into a file, start a new user namespace, then re-read them out of the > tempfile... Not so. You aren't necessarily permitted to read a key - the read function has to be supported by the key type for a start, and then you have to pass all the security checks. David