kern/139226: ipfw: install_state: entry already present, done

[Chris St Denis]

>Number:         139226
>Category:       kern
>Synopsis:       ipfw: install_state: entry already present, done
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Sep 28 23:50:01 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Chris St Denis
>Release:        7.2
>Organization:
>Environment:
FreeBSD webs2.smartt.com 7.2-RELEASE-p2 FreeBSD 7.2-RELEASE-p2 #0: Wed Jun 24 00:14:35 UTC 2009     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
The simple IPFW stateful firewall rule 
"allow udp from me to any keep-state"

in conjunction with named running as a slave for several zones (not published, just replicating)

causes repeated kernel messages 
"ipfw: install_state: entry already present, done"


I doubt named is the actual cause of this of course. The master/slave udp chatter is just a source that triggers this error. I couldn't reproduce the message using something like nc -u, but somebody more familiar with this may be able to.
>How-To-Repeat:
Firewall config
================
Minimum rules method:
--------
Load the firewall as a kernel modue
#kldload ipfw

Add a keep-state UDP rule to the firewall
ipfw add allow udp from me to any keep-state

Alternate method
--------
set the following rc.conf variables to use somewhat more complex built-in "workstation" rule set

firewall_enable="yes"
firewall_type="workstation"


Named config
============
edit name.conf 
Add slave zones. Master server does not need to allow access for this to be triggered, just the slave trying to connect is enough.
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: