The ip_cmsg_recv_checksum function in net/ipv4/ip_sockglue.c in the Linux kernel before 4.10.1 has incorrect expectations about skb data layout, which allows local users to cause a denial of service (buffer over-read) or possibly have unspecified other impact via crafted system calls, as demonstrated by use of the MSG_MORE flag in conjunction with loopback UDP transmission.
https://github.com/torvalds/linux/commit/ca4ef4574f1ee5252e2cd365f8f5d5bafd048f32
https://bugzilla.redhat.com/show_bug.cgi?id=1427984
http://www.securityfocus.com/bid/96487
http://www.openwall.com/lists/oss-security/2017/02/28/5
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.10.1