amd64/154134: stuck kernel state in LISTEN on ipv6 daemon which has been killed

[George Michaelson]

>Number:         154134
>Category:       amd64
>Synopsis:       stuck kernel state in LISTEN on ipv6 daemon which has been killed
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Jan 19 04:50:07 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     George Michaelson
>Release:        8.1
>Organization:
APNIC
>Environment:
FreeBSD wattle.apnic.net 8.1-RELEASE-p2 FreeBSD 8.1-RELEASE-p2 #1: Tue Jan 18 01:06:10 UTC 2011     root at wattle.apnic.net:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
rsync --daemon not accepting v6 rsync calls. TCPDUMP shows packetflow syn/fin.

kill daemon, state left in kernel with netstat -an | grep 873.

add inetd entry tcp6. can't bind to port.

reboot, problem gone.

oddly, ssh and ping6 working, and I see a heap of nd6 neighbour discovery even though the two boxes 'knew' each other when this happened.
>How-To-Repeat:
not sure I can. looks like sometimes, kernel state for listen() in v6 is stuck even if user process goes away.
>Fix:
notknown

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