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 Valhall r39p0 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