Re: [PATCH V6 05/10] audit: log creation and deletion of namespace instances

Paul Moore <pmoore(a)redhat.com&gt; writes: > As Eric, and others, have stated, the container concept is a userspace idea, > not a kernel idea; the kernel only knows, and cares about, namespaces. This > is unlikely to change. > > However, as Steve points out, there is precedence for the kernel to record > userspace tokens for the sake of audit. Personally I'm not a big fan of this > in general, but I do recognize that it does satisfy a legitimate need. Think > of things like auid and the sessionid as necessary evils; audit is already > chock full of evilness I doubt one more will doom us all to hell. > > Moving forward, I'd like to see the following: > * Create a container ID token (unsigned 32-bit integer?), similar to > auid/sessionid, that is set by userspace and carried by the kernel to be used > in audit records. I'd like to see some discussion on how we manage this, e.g. > how do handle container ID inheritance, how do we handle nested containers > (setting the containerid when it is already set), do we care if multiple > different containers share the same namespace config, etc.? > Can we all live with this? If not, please suggest some alternate ideas; > simply shouting "IT'S ALL CRAP!" isn't helpful for anyone ... it may be true, > but it doesn't help us solve the problem ;) Without stopping and defining what someone means by container I think it is pretty much nonsense.

Should every vsftp connection get a container every? Every chrome tab? At some of the connections per second numbers I have seen we might exhaust a 32bit number in an hour or two. Will any of that make sense to someone reading the audit logs?

Without considerning that container creation is an unprivileged operation I think it is pretty much nonsense. Do I get to say I am any container I want? That would seem to invalidate the concept of userspace setting a container id.

How does any of this interact with setns? AKA entering a container?

I will go as far as looking at patches. If someone comes up with a mission statement about what they are actually trying to achieve and a mechanism that actually achieves that, and that allows for containers to nest we can talk about doing something like that.

But for right now I just hear proposals for things that make no sense and can not possibly work. Not least because it will require modifying every program that creates a container and who knows how many of them there are. Especially since you don't need to be root. Modifying /usr/bin/unshare seems a little far out to me.

Eric