arXiv subjects

Mark Silberstein

Publications and source records attributed to Mark Silberstein.

21 records · Page 2Linked to original sources

arXiv2020

A Computational Approach to Packet Classification

Multi-field packet classification is a crucial component in modern software-defined data center networks. To achieve high throughput and low latency, state-of-the-art algorithms strive to fit the rule lookup data structures into on-die caches; however, they do not scale well with the number of rules. We present a novel approach, NuevoMatch, which improves the memory scaling of existing methods. A new data structure, Range Query Recursive Model Index (RQ-RMI), is the key component that enables NuevoMatch to replace most of the accesses to main memory with model inference computations. We describe an efficient training algorithm that guarantees the correctness of the RQ-RMI-based classification. The use of RQ-RMI allows the rules to be compressed into model weights that fit into the hardware cache. Further, it takes advantage of the growing support for fast neural network processing in modern CPUs, such as wide vector instructions, achieving a rate of tens of nanoseconds per lookup. Our evaluation using 500K multi-field rules from the standard ClassBench benchmark shows a geometric mean compression factor of 4.9x, 8x, and 82x, and average performance improvement of 2.4x, 2.6x, and 1.6x in throughput compared to CutSplit, NeuroCuts, and TupleMerge, all state-of-the-art algorithms.

cs.DC↗

arXiv2020

SpecFuzz: Bringing Spectre-type vulnerabilities to the surface

SpecFuzz is the first tool that enables dynamic testing for speculative execution vulnerabilities (e.g., Spectre). The key is a novel concept of speculation exposure: The program is instrumented to simulate speculative execution in software by forcefully executing the code paths that could be triggered due to mispredictions, thereby making the speculative memory accesses visible to integrity checkers (e.g., AddressSanitizer). Combined with the conventional fuzzing techniques, speculation exposure enables more precise identification of potential vulnerabilities compared to state-of-the-art static analyzers. Our prototype for detecting Spectre V1 vulnerabilities successfully identifies all known variations of Spectre V1 and decreases the mitigation overheads across the evaluated applications, reducing the amount of instrumented branches by up to 77% given a sufficient test coverage.

cs.CR↗

arXiv2018

You Shall Not Bypass: Employing data dependencies to prevent Bounds Check Bypass

A recent discovery of a new class of microarchitectural attacks called Spectre picked up the attention of the security community as these attacks can circumvent many traditional mechanisms of defense. One of the attacks---Bounds Check Bypass---can neither be efficiently solved on system nor architectural levels and requires changes in the application itself. So far, the proposed mitigations involved serialization, which reduces the usage of CPU resources and causes high overheads. In this report, we explore methods of delaying the vulnerable instructions without complete serialization. We discuss several ways of achieving it and compare them with Speculative Load Hardening, an existing solution based on a similar idea. The solutions of this type cause 60% overhead across Phoenix benchmark suite, which compares favorably to the full serialization causing 440% slowdown.

cs.CR↗