kern/50366: Multicasts don't work on udav(4)

[rkujawa%netbsd.org@localhost]

>Number:         50366
>Category:       kern
>Synopsis:       Multicasts don't work on udav(4)
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Oct 24 20:45:00 +0000 2015
>Originator:     Radoslaw Kujawa
>Release:        7.99.21
>Organization:
NetBSD
>Environment:
NetBSD rpi 7.99.21 NetBSD 7.99.21 (RPI.201510220400Z) #0: Thu Oct 22 05:33:15 UTC 2015  builds%b46.netbsd.org@localhost:/home/builds/ab/HEAD/evbarm-earmv6hf/201510220400Z-obj/home/source/ab/HEAD/src/sys/arch/evbarm/compile/RPI evbarm
>Description:
While chasing an unrelated bug, I wanted to test multicasts with another ethernet interface. Took an udav(4) lying around. To my surprise, multicasts don't work at all on udav(4). No multicast is ever received.

>How-To-Repeat:
1. Install NetBSD.
2. Plug in udav(4).
3. Send multicasts from another machine
4. See no multicasts received on a machine with udav plugged.

>Fix:
I have no idea. Just a suspicion that it's related to multicast hash filter.