Presentation
Levioso: Efficient Compiler-Informed Secure Speculation
SessionWhat's Your Best Side?
DescriptionSpectre-type attacks have demonstrated a major class of vulnerabilities
arising from speculative execution of instructions, the main performance enabler of modern CPUs. These attacks speculatively leak secrets that have been either speculatively loaded (seen in sandboxed programs) or non-speculatively loaded (seen in constant-time programs). Various hardware-only defenses have been proposed to mitigate both speculative and non-speculative secrets via all potential transmission channels. However, these solution rely on limited knowledge of the hardware about the program to conservatively restrict the execution of all instructions that can potentially leak information.
In this work, we discuss that not all instructions depend on older unresolved branches and they can safely execute without leaking speculative information.
We present Levioso, a novel hardware/software co-design, that provides comprehensive secure speculation guarantees while reducing performance overhead compared to the existing methodologies. Levioso informs the hardware about true branch dependencies in order to apply restrictions only when necessary. Our evaluations demonstrate that Levioso is able to significantly reduce the performance overhead compared to two state-of-the-art defenses from 51% and 43% to just 23%.
arising from speculative execution of instructions, the main performance enabler of modern CPUs. These attacks speculatively leak secrets that have been either speculatively loaded (seen in sandboxed programs) or non-speculatively loaded (seen in constant-time programs). Various hardware-only defenses have been proposed to mitigate both speculative and non-speculative secrets via all potential transmission channels. However, these solution rely on limited knowledge of the hardware about the program to conservatively restrict the execution of all instructions that can potentially leak information.
In this work, we discuss that not all instructions depend on older unresolved branches and they can safely execute without leaking speculative information.
We present Levioso, a novel hardware/software co-design, that provides comprehensive secure speculation guarantees while reducing performance overhead compared to the existing methodologies. Levioso informs the hardware about true branch dependencies in order to apply restrictions only when necessary. Our evaluations demonstrate that Levioso is able to significantly reduce the performance overhead compared to two state-of-the-art defenses from 51% and 43% to just 23%.
Event Type
Research Manuscript
TimeWednesday, June 262:45pm - 3:00pm PDT
Location3012, 3rd Floor
Security
Hardware Security: Attack and Defense