Re: [RFC PATCH ghak32 V2 12/13] audit: NETFILTER_PKT: record each container ID associated with a netNS

[Richard Guy Briggs]

On 2018-04-18 22:10, Paul Moore wrote:
> On Fri, Mar 16, 2018 at 5:00 AM, Richard Guy Briggs <rgb@xxxxxxxxxx> wrote:
> > Add container ID auxiliary record(s) to NETFILTER_PKT event standalone
> > records.  Iterate through all potential container IDs associated with a
> > network namespace.
> >
> > Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
> > ---
> >  kernel/audit.c           |  1 +
> >  kernel/auditsc.c         |  2 ++
> >  net/netfilter/xt_AUDIT.c | 15 ++++++++++++++-
> >  3 files changed, 17 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/audit.c b/kernel/audit.c
> > index 08662b4..3c77e47 100644
> > --- a/kernel/audit.c
> > +++ b/kernel/audit.c
> > @@ -2102,6 +2102,7 @@ int audit_log_container_info(struct audit_context *context,
> >         audit_log_end(ab);
> >         return 0;
> >  }
> > +EXPORT_SYMBOL(audit_log_container_info);
> >
> >  void audit_log_key(struct audit_buffer *ab, char *key)
> >  {
> > diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> > index 208da962..af68d01 100644
> > --- a/kernel/auditsc.c
> > +++ b/kernel/auditsc.c
> > @@ -975,6 +975,7 @@ struct audit_context *audit_alloc_local(void)
> >         context->in_syscall = 1;
> >         return context;
> >  }
> > +EXPORT_SYMBOL(audit_alloc_local);
> >
> >  inline void audit_free_context(struct audit_context *context)
> >  {
> > @@ -989,6 +990,7 @@ inline void audit_free_context(struct audit_context *context)
> >         audit_proctitle_free(context);
> >         kfree(context);
> >  }
> > +EXPORT_SYMBOL(audit_free_context);
> >
> >  static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> >                                  kuid_t auid, kuid_t uid, unsigned int sessionid,
> > diff --git a/net/netfilter/xt_AUDIT.c b/net/netfilter/xt_AUDIT.c
> > index c502419..edaa456 100644
> > --- a/net/netfilter/xt_AUDIT.c
> > +++ b/net/netfilter/xt_AUDIT.c
> > @@ -71,10 +71,14 @@ static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb)
> >  {
> >         struct audit_buffer *ab;
> >         int fam = -1;
> > +       struct audit_context *context = audit_alloc_local();
> > +       struct audit_containerid *cont;
> > +       int i = 0;
> > +       struct net *net;
> >
> >         if (audit_enabled == 0)
> >                 goto errout;
> 
> Do I need to say it?  I probably should ... the allocation should
> happen after the audit_enabled check.

Already fixed in V3 in my tree a couple of weeks ago...
More timely review please?

> > -       ab = audit_log_start(NULL, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
> > +       ab = audit_log_start(context, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
> >         if (ab == NULL)
> >                 goto errout;
> >
> > @@ -104,7 +108,16 @@ static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb)
> >
> >         audit_log_end(ab);
> >
> > +       net = sock_net(NETLINK_CB(skb).sk);
> > +       list_for_each_entry(cont, &net->audit_containerid, list) {
> > +               char buf[14];
> > +
> > +               sprintf(buf, "net%u", i++);
> > +               audit_log_container_info(context, buf, cont->id);
> > +       }
> 
> It seems like this could (should?) be hidden inside an audit function,
> e.g. audit_log_net_containers() or something like that.

Perhaps...  It was open-coded since at this point there are no other
users.  That'll make this tidier though.

> >  errout:
> > +       audit_free_context(context);
> >         return XT_CONTINUE;
> >  }
> 
> -- 
> paul moore
> www.paul-moore.com

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
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