SHAX: Evaluation of SVM hardware accelerator for detecting and preventing ROP on Xtensa

Return-oriented programming (ROP) chains together sequences of instructions residing in executable pages of the memory to compromise a program’s control flow. On embedded systems , ROP detection is intricate as such devices lack the resources to directly run sophisticated software-based detection techniques, as these are memory and CPU-intensive. However, a Field Programmable Gate Array (FPGA) can enhance the capabilities of an embedded device to handle resource-intensive tasks. Hence, this paper presents the first performance evaluation of a Support Vector Machine (SVM) hardware accelerator for automatic ROP classification on Xtensa-embedded devices using hardware performance counters (HPCs). In addition to meeting security requirements, modern cyber–physical systems must exhibit high reliability against hardware failures to ensure correct functionality. To assess the reliability level of our proposed SVM architecture, we perform simulation-based fault injection at the RT-level. To improve the efficiency of this evaluation, we utilize a hybrid virtual prototype that integrates the RT-level model of the SVM accelerator with the Tensilica LX7 Instruction Set Simulator. This setup enables early-stage reliability assessment, helping to identify vulnerabilities and reduce the need for extensive fault injection campaigns during later stages of the design process. Our evaluation results show that an SVM accelerator targeting an FPGA device can detect and prevent ROP attacks on an embedded processor with high accuracy in real time. In addition, we explore the most vulnerable locations of our SVM design to permanent faults, enabling the exploration of safety mechanisms that increase fault coverage in future works.