An issue was discovered in the Arm Mali GPU Kernel Driver. A non-privileged user can make improper GPU processing operations to gain access to already freed memory. This affects Midgard r0p0 through r32p0, Bifrost r0p0 through r41p0 before r42p0, Valhall r19p0 through r41p0 before r42p0, and Avalon r41p0 before r42p0.
https://developer.arm.com/support/arm-security-updates
https://developer.arm.com/Arm%20Security%20Center/Mali%20GPU%20Driver%20Vulnerabilities
http://packetstormsecurity.com/files/172855/Android-Arm-Mali-GPU-Arbitrary-Code-Execution.html