kern/144869: Instant kernel panic when adding NAT rules using ipfw on em interfaces

[Ulf Heiman]

>Number:         144869
>Category:       kern
>Synopsis:       Instant kernel panic when adding NAT rules using ipfw on em interfaces
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Mar 19 11:50:01 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Ulf Heiman
>Release:        8.0-STABLE
>Organization:
>Environment:
FreeBSD rommie.permissiondenied.org 8.0-STABLE FreeBSD 8.0-STABLE #0: Fri Mar 19 09:36:17 CET 2010     root at rommie.permissiondenied.org:/usr/obj/usr/src/sys/GENERIC  i386
>Description:
When adding two simple ipfw nat rules on em0 the kernel instantly panics and the server reboots. The issue can be avoided by running 'ifconfig em0 -rxcsum' prior to adding the ipfw nat rules.
>How-To-Repeat:
After a fresh reboot run the following commands:
kldload ipfw_nat
ipfw nat 1 config if em0 same_ports
ipfw add 10000 nat 1 ip from any to any via em0
>Fix:


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