一句话：提出 Chord，通过统一冲突交易模型与动态测试编排，统一检测多种区块链的交易并行性缺陷。
区块链为提升吞吐、降低延迟引入了多种交易并行机制，但也不可避免地引入缺陷，可能导致资产损失、双花、共识失败与 DDoS 等严重后果。然而，现有工作对这些缺陷的症状与根因缺乏分析，也缺少有效检测手段。本文首先对四个商业区块链中的历史交易并行性缺陷进行深入分析，发现多数缺陷源于冲突交易处理不当，且在运行中无明显现象。由于区块链异构性，统一触发冲突处理十分困难。受此启发，作者提出 Chord：它设计统一的冲突交易模型以生成各类冲突交易，动态调整交易提交并在执行中插入主动回滚以进行充分测试，同时结合本地—远程差分预言与 TPS 预言捕获缺陷。评估表明，Chord 成功检测出 54 个交易并行性缺陷，并使 TPS 下降 49.7%、延迟上升 388.0%，优于现有方法，显示出其触发各类冲突场景并暴露缺陷的有效性。
Blockchain systems have implemented various transaction parallelism mechanisms to improve the system throughput and reduce the latency. However, they inevitably introduce bugs. Such bugs can result in severe consequences such as asset loss, double spending, consensus failure, and DDoS. Unfortunately, they have been little analyzed about their symptoms and root causes, leading to a lack of effective detection methods. In this work, we conduct a thorough analysis of historical transaction parallelism bugs in four commercial blockchains. Results show that most of them arise from mishandling conflicting transactions and manifest without obvious phenomena. However, given the heterogeneity of blockchains, it is challenging to trigger conflict handling in a unified way. Effectively identifying these bugs is also hard. Inspired by the findings, we propose Chord, aiming at detecting blockchain transaction parallelism bugs. Chord proposes a unified conflict transaction model to generate various conflict transactions. Chord also dynamically adjust the transaction submission and inserts proactive reverts during transaction execution to conduct thorough testing. Besides, Chord incorporates a local-remote differential oracle and a TPS oracle to capture the bugs. Our evaluation shows that Chord successfully detects 54 transaction parallelism bugs. Besides, Chord outperforms the existing methods by decreasing the TPS by 49.7% and increasing the latency by 388.0%, showing its effectiveness in triggering various conflict scenarios and exposing the bugs.
DOI 原文 ·
@inproceedings{paperbot8903,
title = {Chord: Towards a Unified Detection of Blockchain Transaction Parallelism Bugs},
author = {Yuanhang Zhou and Zhen Yan and Yuanliang Chen and Fuchen Ma and Ting Chen and Yu Jiang},
booktitle = {ICSE},
year = {2025},
doi = {10.1109/icse55347.2025.00205}
}