kern/43186: multicast packets aren't received when PROMISC mode on fxp.

[kimoto%soum.co.jp@localhost]

>Number:         43186
>Category:       kern
>Synopsis:       multicast packets aren't received when PROMISC mode on fxp.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Apr 21 05:50:00 +0000 2010
>Originator:     Masahiko KIMOTO
>Release:        5.99.27
>Organization:
SOUM Corporation
>Environment:
NetBSD gaia.earthlight.jp 5.99.27 NetBSD 5.99.27 (GENERIC) #3: Thu Apr 15 
21:39:38 JST 2010  
kimoto%gaia.earthlight.jp@localhost:/local/home/kimoto/work/source/netbsd/build/obj/sys/arch/i386/compile/GENERIC
 i386

>Description:
When I set promiscus mode on fxp interface, multicast packets
which the host doesn't joined address are not received.
>How-To-Repeat:
set promiscus flag on fxp. tcpdump on the interface and send
multicast packets to not-joined address. they does note been 
observed.
>Fix:
Intel NIC has two flags for promiscus mode, one for unicast and another is for 
multicast.
When the user set promiscus mode flag on the interface, both flags should be 
set.
However current code (including -current) set only unicast promiscus flag.
fxp.c on OpenBSD fixed this problem. Please refer and import it.