GWP-ASan: Sampling-Based Detection of Memory-Safety Bugs in Production

Kostya Serebryany; Chris Kennelly; Mitch Phillips; Matt Denton; Marco Elver; Alexander Potapenko; Matt Morehouse; Vlad Tsyrklevich; Christian Holler; Julian Lettner; David Kilzer; Lander Brandt

arXiv · 2311.09394

GWP-ASan: Sampling-Based Detection of Memory-Safety Bugs in Production

Kostya Serebryany·Chris Kennelly·Mitch Phillips·Matt Denton·Marco Elver·Alexander Potapenko·Matt Morehouse·Vlad Tsyrklevich·Christian Holler·Julian Lettner·David Kilzer·Lander Brandt

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Abstract

Despite the recent advances in pre-production bug detection, heap-use-after-free and heap-buffer-overflow bugs remain the primary problem for security, reliability, and developer productivity for applications written in C or C++, across all major software ecosystems. Memory-safe languages solve this problem when they are used, but the existing code bases consisting of billions of lines of C and C++ continue to grow, and we need additional bug detection mechanisms. This paper describes a family of tools that detect these two classes of memory-safety bugs, while running in production, at near-zero overhead. These tools combine page-granular guarded allocation and low-rate sampling. In other words, we added an "if" statement to a 36-year-old idea and made it work at scale. We describe the basic algorithm, several of its variants and implementations, and the results of multi-year deployments across mobile, desktop, and server applications.

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Kostya Serebryany, Chris Kennelly, Mitch Phillips, Matt Denton, Marco Elver, Alexander Potapenko, Matt Morehouse, Vlad Tsyrklevich, Christian Holler, Julian Lettner, David Kilzer, Lander Brandt. 2023-11-15. GWP-ASan: Sampling-Based Detection of Memory-Safety Bugs in Production. https://arxiv.org/abs/2311.09394

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