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Title: Exploiting Logic Locking for a Neural Trojan Attack on Machine Learning Accelerators
Logic locking has been proposed to safeguard intellectual property (IP) during chip fabrication. Logic locking techniques protect hardware IP by making a subset of combinational modules in a design dependent on a secret key that is withheld from untrusted parties. If an incorrect secret key is used, a set of deterministic errors is produced in locked modules, restricting unauthorized use. A common target for logic locking is neural accelerators, especially as machine-learning-as-a-service becomes more prevalent. In this work, we explore how logic locking can be used to compromise the security of a neural accelerator it protects. Specifically, we show how the deterministic errors caused by incorrect keys can be harnessed to produce neural-trojan-style backdoors. To do so, we first outline a motivational attack scenario where a carefully chosen incorrect key, which we call a trojan key, produces misclassifications for an attacker-specified input class in a locked accelerator. We then develop a theoretically-robust attack methodology to automatically identify trojan keys. To evaluate this attack, we launch it on several locked accelerators. In our largest benchmark accelerator, our attack identified a trojan key that caused a 74% decrease in classification accuracy for attacker-specified trigger inputs, while degrading accuracy by only 1.7% for other inputs on average.  more » « less
Award ID(s):
2245573
PAR ID:
10478243
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ACM
Date Published:
Journal Name:
GLSVLSI '23: Proceedings of the Great Lakes Symposium on VLSI 2023
ISBN:
9798400701252
Page Range / eLocation ID:
351 to 356
Subject(s) / Keyword(s):
Logic Locking Neural Trojan Untrusted Foundry Problem Machine Learning Accelerator
Format(s):
Medium: X
Location:
Knoxville TN USA
Sponsoring Org:
National Science Foundation
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