Double free vulnerability in the xfrm6_tunnel_rcv function in net/ipv6/xfrm6_tunnel.c in the Linux kernel before 2.6.22, when the xfrm6_tunnel module is enabled, allows remote attackers to cause a denial of service (panic) via crafted IPv6 packets.
https://bugzilla.redhat.com/show_bug.cgi?id=752304
http://www.securitytracker.com/id?1026930
http://www.securityfocus.com/bid/53139
http://secunia.com/advisories/48881
http://rhn.redhat.com/errata/RHSA-2012-0488.html
http://marc.info/?l=bugtraq&m=133951357207000&w=2
http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.22