kernel: bridge br_multicast null ptr deref

[Eugene Teo <eugeneteo () kernel sg>]

Introduced in commit 8ef2a9a5 (v2.6.35-rc1), fixed in 7f285fa78d4. Can 
be triggered with an IGMP packet with no multicast table allocated.

Bug report, http://www.spinics.net/lists/netdev/msg134414.html. Not 
requesting a CVE for this, just FYI.

Thanks, Eugene
--
main(i) { putchar(182623909 >> (i-1) * 5&31|!!(i<7)<<6) && main(++i); }