Implementing Rowhammer Memory Corruption in the gem5 Simulator

Abstract

Modern computer memories have shown to have reliability issues. The main memory is the target of a security threat called Rowhammer, which causes bit flips in adjacent victim cells of aggressor rows. Numerous countermeasures have been proposed, some of the most efficient ones relying on memory controller modifications, which make them non-integrable in existing systems. These solutions have to be effective against attacks on current and future architectures and technology nodes. In order to prove the efficiency of such mitigation techniques, we have to use simulation platforms. Unfortunately, existing architecture simulators do not provide any implementation of unintended memory modifications like bit-flips. Integrating memory corruption into architecture simulators would allow the construction of attacks and mitigations for current and future computers, using feedback from the simulator. In this paper, we propose an implementation of the Rowhammer effect in the gem5 architecture simulator, demonstrate its capabilities and state its limitations.