The bad_mode function in arch/arm64/kernel/traps.c in the Linux kernel before 3.9.5 on the ARM64 platform allows local users to cause a denial of service (system crash) via vectors involving an attempted register access that triggers an unexpected value in the Exception Syndrome Register (ESR).
https://bugzilla.redhat.com/show_bug.cgi?id=996380
http://www.openwall.com/lists/oss-security/2013/08/08/12