Mohabi: Disaggregating and Sandboxing the Firefox JavaScript Engine
6 hours ago
- Mohabi is a modern Firefox browser with a securely sandboxed JavaScript engine (SpiderMonkey) using software-based fault isolation (SFI).
- The JavaScript engine was disaggregated from the rest of the browser, requiring complex transformation across data structures and control flow.
- An optimized SFI toolchain was developed to handle large memory footprints and unique JavaScript engine challenges.
- Mohabi incurs modest overheads: 24.82% on JetStream and 24.43% on Speedometer benchmarks.
- The x86-64 SFI toolchain is the fastest to date, with overheads between 5.9%–6.6% on SPEC 2017.
- This is the most ambitious case study of retrofitting in-process sandboxing in a large system.