This Metasploit module exploits a race and use-after-free vulnerability in the FreeBSD kernel IPv6 socket handling. A missing synchronization lock in the IPV6_2292PKTOPTIONS option handling in setsockopt permits racing ip6_setpktopt access to a freed ip6_pktopts struct. This exploit overwrites the ip6po_pktinfo pointer of a ip6_pktopts struct in freed memory to achieve arbitrary kernel read/write.
