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Date:   Thu, 12 Mar 2020 15:30:37 -0400
From:   Richard Guy Briggs <rgb@redhat.com>
To:     Paul Moore <paul@paul-moore.com>
Cc:     Steve Grubb <sgrubb@redhat.com>, linux-audit@redhat.com,
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        linux-fsdevel@vger.kernel.org, Eric Paris <eparis@parisplace.org>,
        mpatel@redhat.com, Serge Hallyn <serge@hallyn.com>
Subject: Re: [PATCH ghak90 V8 07/16] audit: add contid support for signalling
 the audit daemon
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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.

> paul moore

- RGB

--
Richard Guy Briggs <rgb@redhat.com>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635