Securing UnSafe Rust Programs with XRust

Rust is a promising systems programming language that embraces both high-level memory safety and low-level resource manipulation. However, the dark side of Rust, unsafe Rust, leaves a large security hole as it bypasses the Rust type system in order to support low-level operations. Recently, several real-world memory corruption vulnerabilities have been discovered in Rust's standard libraries. We present XRust, a new technique that mitigates the security threat of unsafe Rust by ensuring the integrity of data flow from unsafe Rust code to safe Rust code. The cornerstone of XRust is a novel heap allocator that isolates the memory of unsafe Rust from that accessed only in safe Rust, and prevents any cross-region memory corruption. Our design of XRust supports both single- and multi-threaded Rust programs. Our extensive experiments on real-world Rust applications and standard libraries show that XRust is both highly efficient and effective in practice.