arch/s390/kernel/head64.S in the Linux kernel before 3.13.5 on the s390 platform does not properly handle attempted use of the linkage stack, which allows local users to cause a denial of service (system crash) by executing a crafted instruction.
http://linux.oracle.com/errata/ELSA-2014-0771.html
http://secunia.com/advisories/59262
http://secunia.com/advisories/59309
http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.13.5
http://www.openwall.com/lists/oss-security/2014/02/20/14
http://www.securityfocus.com/bid/65700
https://bugzilla.redhat.com/show_bug.cgi?id=1067558
https://github.com/torvalds/linux/commit/8d7f6690cedb83456edd41c9bd583783f0703bf0