A Deep Investigation on Stealthy DVFS Fault Injection Attacks at DNN Hardware Accelerators

With increasing computation of various applications, dynamic voltage and frequency scaling (DVFS) is gradually deployed on FPGAs to improve performance and save energy. However, its reliability and security have not been sufficiently evaluated, which incurs quite many concerns. In this article, we propose an evaluation framework for deep investigation of stealthy DVFS fault injection attacks on the state-of-the-art deep neural networks (DNNs) deployed on modern FPGAs. The evaluation framework mainly consists of a DVFS attack striker and a time-to-digital converter (TDC)-based hardware profiler. Two modes of evaluation are derived, and their effectiveness is demonstrated on a platform composed of a SkyNet accelerator and three ImageNet models built on a Xilinx deep learning processor unit (DPU). Experimental results show that more than 99% detection accuracy loss can be measured targeting at all tested DNN models under prospective operation mode but without any performance degradation in frame per second (FPS). In our investigation of sensitive layer mode, more than 93% average accuracy loss with 84.7% fault probability can be measured on a single bundle of the SkyNet. We characterize the vulnerabilities of different DNN layers subject to DVFS attacks through leveraging the TDC-based hardware profiler to precisely control the timing of fault injection.