> > Are there any interfaces, besides lo0, that are DLT_NULL ?
> 
> I've fixed the if_ieee1394subr.c, which is not DLT_NULL actually.
> 
> Just looking net/ director only, I've found these files should be fixed.
> 	if_loop.c
> 	if_sl.c
> 	if_strip.c
> 	if_tun.c
> 
> 	if_faith.c
> 	if_gif.c
> 	if_stf.c
> 
> Note that the last three is the files from KAME and should be fixed in
> the KAME tree.

and 2 more files found:
	netinet/ip_gre.c
	netinet/i4b_ipr.c

Note that I only check whether it uses dummy mbuf from the stack.
I'm not sure that the pkthdr is initialized correctly before calling
bpf_mtap() for other places.

Atsushi Onoe