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Scheduler side-channels can leak critical information in real-time systems, thus posing serious threats to many safety-critical applications. The main culprit is the inherent determinism in the runtime timing behavior of such systems, e.g., the (expected) periodic behavior of critical tasks. In this paper, we introduce the notion of "schedule indistinguishability/", inspired by work in differential privacy, that introduces diversity into the schedules of such systems while offering analyzable security guarantees. We achieve this by adding a sufficiently large (controlled) noise to the task schedules in order to break their deterministic execution patterns. An "epsilon-Scheduler" then implements schedule indistinguishability in real-time Linux. We evaluate our system using two real applications: (a) an autonomous rover running on a real hardware platform (Raspberry Pi) and (b) a video streaming application that sends data across large geographic distances. Our results show that the epsilon-Scheduler offers better protection against scheduler side-channel attacks in real-time systems while still maintaining good performance and quality-of-service(QoS) requirements.
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This content will become publicly available on April 9, 2026
RESCUE: A Reconfigurable Scheduling Framework for Securing Multi-Core Real-Time Systems
Modern real-time systems face increasing vulnerabilities to cyber-attacks, particularly those that use multi-core chips, where safety-critical and non-safety-critical tasks execute concurrently. Existing solutions for multicore systems often lack either determinism or cost-efficiency. This paper introduces an offline analysis technique that computes all feasible schedules for real-time tasks running on multi-core platforms. Our proposed technique isolates compromised tasks while ensuring a fail-operational system and supports low-cost, reconfigurable scheduling. The analytical models presented in this paper guarantee the hard real-time constraints of safety-critical tasks while allowing bounded deadline misses for some non-safety-critical tasks during an attack to enhance security. We name our scheme RESCUE. We conduct a comprehensive design-space exploration and evaluate its real-world efficacy using a UAV autopilot system case study deployed on a quad-core platform (Raspberry Pi). Results show that the proposed scheme introduces minimal recovery overhead, measured in microseconds on a Raspberry Pi, and achieves 100% coverage in reconfiguration responses to compromised tasks in synthetic test cases.
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- Award ID(s):
- 2312006
- PAR ID:
- 10596372
- Publisher / Repository:
- ACM
- Date Published:
- Journal Name:
- ACM Transactions on Cyber-Physical Systems
- ISSN:
- 2378-962X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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