kern/128260: [ipfw] [patch] ipfw_divert damages IPv6 packets

[Dan Lukes]

The following reply was made to PR kern/128260; it has been noted by GNATS.

From: Dan Lukes <dan at obluda.cz>
To: bug-followup at FreeBSD.org
Cc:  
Subject: Re: kern/128260: [ipfw] [patch] ipfw_divert damages IPv6 packets
Date: Mon, 06 Sep 2010 12:08:48 +0200

 The 8.1-RELEASE partially corrects such problem.
 
 But for DIVERT (not the TEE) there are still issues.
 
 For non-tee case, the header is still unconditionally considered to be 
 (struct ip). The
 ip->ip_off & (IP_MF | IP_OFFMASK)
 may be unintentionally true (for a IPv6 packet), then ip_reass will be 
 called with IPv6 packet, which is not apropriate.
 
 We still need to check the IP version:
 
 -       if (!tee && ntohs(ip->ip_off) & (IP_MF | IP_OFFMASK)) {
 +       if (ip->ip_v == 4 && !tee && ntohs(ip->ip_off) & (IP_MF | 
 IP_OFFMASK)) {
 
 Dan