kern/143846: bringing gif3 tunnel down causes gif0 tunnel to stop working

[rick norman]

>Number:         143846
>Category:       kern
>Synopsis:       bringing gif3 tunnel down causes gif0 tunnel to stop working
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Feb 12 20:40:01 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     rick norman
>Release:        7.2 release
>Organization:
>Environment:
FreeBSD 7.2-Release FreeBSD 7-2 Release #4: Tue Dec 15 2009
>Description:
I am running in a vmware workstation environment.  I have two nodes connected by a tunnel.  node01 has 3 gifs, the first one is a tunnel to node02.  Multicat pings from the inner address on node02 to the inner address on node01 work perfectly.  If I then bring down gif2 on node01, via ifconfig gif2 down, The multicat ping ceases receiving any responses.  gif2 is pointed to an unrelated address and should have no effect. Bringing gif2 back up has no restorative effect.  tcpdump shows the ping packets go across the net but no responses are generated.
>How-To-Repeat:
The following configuration should reproduce the problem.

node01
ifconfig em1 alias 10.66.0.1/24
ifconfig gif0 create
ifconfig gif0 tunnel 10.66.0.1 10.66.0.2
ifconfig gif0 10.7.223.1 10.7.223.2 netmask 255.255.255.255
ifconfig gif1 create
ifconfig gif1 tunnel 10.66.0.1 10.66.0.3
ifconfig gif1 10.7.224.1 10.7.224.3 netmask 255.255.255.255
ifconfig gif2 create
ifconfig gif2 tunnel 10.66.0.1 10.66.0.4
ifconfig gif2 10.7.225.1 10.7.225.4 netmask 255.255.255.255

node02
ifconfig em1 alias 10.66.0.2/24
ifconfig gif0 create
ifconfig gif0 tunnel 10.66.0.2 10.66.0.1
ifconfig gif0 10.7.223.2 10.7.223.1 netmask 255.255.255.255
 
Start a ping on node02 and see that it's working. 
ping -I 10.7.223.2 224.0.0.5
 
Bring down gif2 on node01.
ifconfig gif2 down
 
The ping on node02 no longer sees responses.  This happens consistently.
Bringing gif2 back up has no effect.

>Fix:
unknown

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