Run-Time Protection of Multi-Core Processors from Power-Noise Denial-of-Service Attacks

In this paper, we show that stress-tests can be potentially used as power-noise viruses in denial-of-service (DoS) attacks by causing voltage emergencies that may lead to data corruptions and system crashes in multi-core processors. This attack targets processors whose operating voltage has been reduced in-the-field for improving energy efficiency. To protect such undervolted processors from this type of attacks, we present a run-time system for detecting and mitigating power-noise viruses. We present voltage noise data from power-noise viruses and benchmarks collected from an Arm multi-core processor, and we observe that the frequency of voltage emergencies dramatically increases during the execution of power-noise attacks. Based on this observation, we propose a regression model that allows for a run-time estimation of the severity of voltage emergencies by monitoring the frequency of voltage emergencies and the operating frequency of the processor. For mitigating the problem, during the execution of critical tasks requiring protection, our system periodically evaluates the severity of voltage emergencies and adapts the operating frequency of the processor in order to reduce the severity of the attack according to a predefined constraint. We demonstrate the efficiency of the proposed run-time protection system on an actual Arm multi-core processor using two power-noise viruses, and we explore trade-offs between protection latency, CPU utilization and power cost. The proposed software achieves with a very low CPU utilization overhead of less than 0.11% to detect and mitigate power-noise DoS attacks with a latency of 100 μmathrm s.