Eviction Set Construction Can Be Faster and Victim Interference Less in Cache Side-channel Attacks

Obtaining proper eviction sets is crucial for the success of conflict-based cache side-channel attacks. A minimal eviction set contains just enough addresses mapped to the target cache set. Developing efficient search algorithms that incur the lowest latency with the highest success rate is important. Most existing search algorithms need to trick the victim into accessing the target address numerous times, which might be infeasible in some restricted scenarios. It is therefore important for the attacker to minimize the times of victim accesses. For this reason, the Fast and Firm Probe Twice (FPT) algorithm is proposed. It can quickly produce an eviction set with extraordinarily few victim accesses. FPT has been compared against Prime, Prune and Probe (PPP), Group Elimination (GE) and Conflict Test (CT) algorithms on Intel processors. The results show that FPT is preferred among existing algorithms.