Low-Noise Llc Side-Channel Attack With Perf

Many cache side-channel attacks have been proposed, and they threaten sensitive programs in real-world. The success of the attacks depends on how accurately to decide whether a set of cache lines are in cache or not. However, external factors insert noise into cache attacks, and the noise disturbs the attacks' decision process. Attacks in last-level cache (LLC) have more noise compared with core-dedicated caches.In this paper, we propose an attack method using Perf-a performance analyzing tool in Linux, attack(Perf), to achieve low-noise in cache side-channel attacks to LLC. The proposed method utilizes Perf to decide cache hits/misses when accessing memory. Since Perf gets the number of cache hits and misses from hardware performance counters, it can identify the cache hits/misses of memory accesses with the less noise. For evaluation, we compare the performance of attack(stimer) (existing attack method) and attacks(Perf) by implementing Flush+Reload and Prime+Probe. For the accuracy of Perf, we compare the clock cycles of the timer and the counts of Perf according to the victim's access.