The sock_setsockopt function in net/core/sock.c in the Linux kernel before 3.5.7 does not ensure that a keepalive action is associated with a stream socket, which allows local users to cause a denial of service (system crash) by leveraging the ability to create a raw socket.
https://bugzilla.redhat.com/show_bug.cgi?id=1141742
http://www.openwall.com/lists/oss-security/2014/09/15/8
http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.5.7
http://marc.info/?l=bugtraq&m=142722544401658&w=2
http://marc.info/?l=bugtraq&m=142722450701342&w=2
http://lists.opensuse.org/opensuse-security-announce/2015-04/msg00020.html
http://lists.opensuse.org/opensuse-security-announce/2015-04/msg00000.html