Race condition in the ip4_datagram_release_cb function in net/ipv4/datagram.c in the Linux kernel before 3.15.2 allows local users to gain privileges or cause a denial of service (use-after-free) by leveraging incorrect expectations about locking during multithreaded access to internal data structures for IPv4 UDP sockets.
https://github.com/torvalds/linux/commit/9709674e68646cee5a24e3000b3558d25412203a
http://www.securitytracker.com/id/1037798
http://www.securityfocus.com/bid/96100
http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.15.2