On 2019-05-29 18:17, Paul Moore wrote:

On Mon, Apr 8, 2019 at 11:41 PM Richard Guy Briggs [off-list ref] wrote:

quoted

Audit events could happen in a network namespace outside of a task
context due to packets received from the net that trigger an auditing
rule prior to being associated with a running task.  The network
namespace could be in use by multiple containers by association to the
tasks in that network namespace.  We still want a way to attribute
these events to any potential containers.  Keep a list per network
namespace to track these audit container identifiiers.

Add/increment the audit container identifier on:
- initial setting of the audit container identifier via /proc
- clone/fork call that inherits an audit container identifier
- unshare call that inherits an audit container identifier
- setns call that inherits an audit container identifier
Delete/decrement the audit container identifier on:
- an inherited audit container identifier dropped when child set
- process exit
- unshare call that drops a net namespace
- setns call that drops a net namespace

Please see the github audit kernel issue for contid net support:
  https://github.com/linux-audit/audit-kernel/issues/92
Please see the github audit testsuiite issue for the test case:
  https://github.com/linux-audit/audit-testsuite/issues/64
Please see the github audit wiki for the feature overview:
  https://github.com/linux-audit/audit-kernel/wiki/RFE-Audit-Container-ID
Signed-off-by: Richard Guy Briggs <redacted>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 include/linux/audit.h | 19 +++++++++++
 kernel/audit.c        | 88 +++++++++++++++++++++++++++++++++++++++++++++++++--
 kernel/nsproxy.c      |  4 +++
 3 files changed, 108 insertions(+), 3 deletions(-)

...

quoted

diff --git a/kernel/audit.c b/kernel/audit.c
index 6c742da66b32..996213591617 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c

@@ -376,6 +384,75 @@ static struct sock *audit_get_sk(const struct net *net)
        return aunet->sk;
 }

+void audit_netns_contid_add(struct net *net, u64 contid)
+{
+       struct audit_net *aunet;
+       struct list_head *contid_list;
+       struct audit_contid *cont;
+
+       if (!net)
+               return;
+       if (!audit_contid_valid(contid))
+               return;
+       aunet = net_generic(net, audit_net_id);
+       if (!aunet)
+               return;
+       contid_list = &aunet->contid_list;
+       spin_lock(&aunet->contid_list_lock);
+       list_for_each_entry_rcu(cont, contid_list, list)
+               if (cont->id == contid) {
+                       refcount_inc(&cont->refcount);
+                       goto out;
+               }
+       cont = kmalloc(sizeof(struct audit_contid), GFP_ATOMIC);
+       if (cont) {
+               INIT_LIST_HEAD(&cont->list);

I thought you were going to get rid of this INIT_LIST_HEAD() call?

I was intending to, and then Neil weighed in with this opinion:

	https://www.redhat.com/archives/linux-audit/2019-April/msg00014.html

If you feel that isn't important, please remove it.

quoted

+               cont->id = contid;
+               refcount_set(&cont->refcount, 1);
+               list_add_rcu(&cont->list, contid_list);
+       }
+out:
+       spin_unlock(&aunet->contid_list_lock);
+}

--
paul moore
www.paul-moore.com

- RGB

--
Richard Guy Briggs [off-list ref]
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