This post started out of the need to provide a little more clarification after a long and heated discussions on Twitter (initial discussion and follow up) about the origins of Control-Flow Integrity (CFI), the contributions of academia, and the precision, performance, and compatibility of different existing implementations.

CFI is a stop the exploit defense that protects the control-flow of processes in the presence of memory corruption. The threat model assumes that an attacker can modify (read, write, update) all of the address space according to the read/write permissions of the corresponding pages. The mitigation restricts execution to valid control flows by checking the targets of indirect control flow transfers (indirect calls and indirect jumps on the forward edge or function returns on the backward edge).