Deterministically Deterring
Timing Attacks in Deterland

Weiyi Wu and Bryan Ford
Yale University

Conference on Timely Results in Operating Systems (TRIOS)
October 4, 2015, Monterey, CA, USA


The massive parallelism and resource sharing embodying today’s cloud business model not only exacerbate the security challenge of timing channels, but also undermine the viability of defenses based on resource partitioning. We propose hypervisor-enforced timing mitigation to control timing channels in cloud environments. This approach closes “reference clocks” internal to the cloud by imposing a deterministic view of time on guest code, and uses timing mitigators to pace I/O and rate-limit potential information leakage to external observers. Our prototype hypervisor is the first system to mitigate timing-channel leakage across full-scale existing operating systems such as Linux and applications in arbitrary languages. Mitigation incurs a varying performance cost, depending on workload and tunable leakage-limiting parameters, but this cost may be justified for security-critical cloud applications and data.

Paper: PDF

Slides: OpenOffice PDF

This research is sponsored by the National Science Foundation under grants CNS-1017206, CNS-1149936, and CNS-1407454.