[strcat]

AOSP not permitting setuid/setgid binaries is certainly useful attack surface reduction but isn't how it blocks exploiting this vulnerability. It blocks it via SELinux policy having allowlists for socket types which don't permit AF_ALG to be used outside of the dumpstate service.

The vulnerability also isn't present in standard AOSP GKI kernels (including the stock Pixel OS) or GrapheneOS kernels since they use a minimal kernel with tons of functionality disabled.

Kernel attack surface is mainly done via SELinux policies on AOSP including ioctl command allowlists per device type such as permitted GPU driver ioctl commands, io_uring only being permitted for a few core processes and much more. AOSP uses seccomp-bpf for apps, etc. too but it's mainly SELinux doing kernel attack surface reduction in practice.