🤖 AI Summary
SyzHarness结合大语言模型与覆盖引导的模糊测试,有效解决了Linux内核漏洞复现问题,通过补丁合成模糊测试框架,提高漏洞触发成功率。
📝 Abstract
Automated kernel vulnerability reproduction is essential for bug triage, patch validation, and regression testing, but
still lacks an effective and efficient solution. The core challenge is twofold: a reproducer must first recover the
trigger scaffold needed to reach the vulnerable state and determine the precise concrete values that actually trigger
the bug. Existing directed fuzzing approaches are ineffective at recovering the necessary trigger scaffold, while LLM-
only generation is brittle because it struggles with concrete-value discovery and runtime nondeterminism. We design
SyzHarness, a framework that combines LLM reasoning with coverage-guided fuzzing for patch-based Linux kernel
vulnerability reproduction. Given a patch, SyzHarness uses an LLM agent grounded by code navigation tools to
synthesize a parameterized fuzzing harness that fixes the prerequisite setup logic while exposing only uncertain, bug-
critical input parameters to be mutated by Syzkaller. SyzHarness then translates this harness into a Syzkaller-
compatible interface and iteratively refines it using hierarchical reachability feedback. We evaluate SyzHarness on
multiple datasets of triggerable real-world Linux kernel vulnerabilities. On 100 KernelCTF cases, SyzHarness achieves
a 78% bug reproduction success rate. On the SyzDirect benchmark, SyzHarness achieves a 73% bug reproduction success
rate, substantially outperforming prior directed greybox fuzzing. On 50 recent, known-triggerable syzbot bugs fixed
after March 2026, SyzHarness reproduces 40/50 (80%) using only the fix commits as input.