On Scheduler Side-Channels in Dynamic-Priority Real-Time Systems
This addresses a security vulnerability for real-time systems using dynamic scheduling, such as EDF, by revealing a previously unexplored side-channel, though it is incremental as it extends known attacks from fixed-priority systems.
The paper tackled the problem of scheduler side-channels in dynamic-priority real-time systems, demonstrating that such side-channels exist and enabling the DyPS algorithm to infer critical task information with high precision from an unprivileged task, outperforming the state-of-the-art ScheduLeak algorithms.
While the existence of scheduler side-channels has been demonstrated recently for fixed-priority real-time systems (RTS), there have been no similar explorations for dynamic-priority systems. The dynamic nature of such scheduling algorithms, e.g., EDF, poses a significant challenge in this regard. In this paper we demonstrate that side-channels exist in dynamic priority real-time systems. Using this side-channel, our proposed DyPS algorithm is able to effectively infer, with high precision, critical task information from the vantage point of an unprivileged (user space) task. Apart from demonstrating the effectiveness of DyPS, we also explore the various factors that impact such attack algorithms using a large number of synthetic task sets. We also compare against the state-of-the-art and demonstrate that our proposed DyPS algorithms outperform the ScheduLeak algorithms in attacking the EDF RTS.