Re: [PATCH ghak90 V8 07/16] audit: add contid support for signalling the audit daemon

On 2020-03-13 12:29, Paul Moore wrote: > On Thu, Mar 12, 2020 at 3:30 PM Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > > On 2020-02-13 16:44, Paul Moore wrote: > > > This is a bit of a thread-hijack, and for that I apologize, but > > > another thought crossed my mind while thinking about this issue > > > further ... Once we support multiple auditd instances, including the > > > necessary record routing and duplication/multiple-sends (the host > > > always sees *everything*), we will likely need to find a way to "trim" > > > the audit container ID (ACID) lists we send in the records. The > > > auditd instance running on the host/initns will always see everything, > > > so it will want the full container ACID list; however an auditd > > > instance running inside a container really should only see the ACIDs > > > of any child containers. > > > > Agreed. This should be easy to check and limit, preventing an auditd > > from seeing any contid that is a parent of its own contid. > > > > > For example, imagine a system where the host has containers 1 and 2, > > > each running an auditd instance. Inside container 1 there are > > > containers A and B. Inside container 2 there are containers Y and Z. > > > If an audit event is generated in container Z, I would expect the > > > host's auditd to see a ACID list of "1,Z" but container 1's auditd > > > should only see an ACID list of "Z". The auditd running in container > > > 2 should not see the record at all (that will be relatively > > > straightforward). Does that make sense? Do we have the record > > > formats properly designed to handle this without too much problem (I'm > > > not entirely sure we do)? > > > > I completely agree and I believe we have record formats that are able to > > handle this already. > > I'm not convinced we do. What about the cases where we have a field > with a list of audit container IDs? How do we handle that? I don't understand the problem. (I think you crossed your 1/2 vs A/B/Y/Z in your example.) ...

... Clarifying the example above, if as you suggest an event happens in container Z, the hosts's auditd would report Z,^2 and the auditd in container 2 would report Z,^2 but if there were another auditd running in container Z it would report Z while the auditd in container 1 or A/B would see nothing.