The libfuzzer-sys Crate

Barebones wrapper around LLVM's libFuzzer runtime library.

The CPP parts are extracted from compiler-rt git repository with git filter-branch.

libFuzzer relies on LLVM sanitizer support. The Rust compiler has built-in support for LLVM sanitizer support, for now, it's limited to Linux. As a result, libfuzzer-sys only works on Linux.

Usage

Use cargo fuzz!

The recommended way to use this crate with cargo fuzz!.

Manual Usage

This crate can also be used manually as following:

First create a new cargo project:

$ cargo new --bin fuzzed $ cd fuzzed

Then add a dependency on the fuzzer-sys crate and your own crate:

toml [dependencies] libfuzzer-sys = "0.2.0" your_crate = { path = "../path/to/your/crate" }

Change the fuzzed/src/main.rs to fuzz your code:

```rust

![no_main]

use libfuzzersys::fuzztarget;

fuzz_target!(|data: &[u8]| { // code to fuzz goes here }); ```

Build by running the following command:

sh $ cargo rustc -- \ -C passes='sancov' \ -C llvm-args='-sanitizer-coverage-level=3' \ -Z sanitizer=address

And finally, run the fuzzer:

sh $ ./target/debug/fuzzed

Updating libfuzzer from upstream

./update-libfuzzer.sh <llvm/compiler-rt SHA1>

License

All files in libfuzzer directory are licensed NCSA.

Everything else is dual-licensed Apache 2.0 and MIT.