Fuzz ReScript parser

This is an example repository of a fuzing tutorial. If you want to find more detailed manual, please refer to it. For now, this instruction has only been demonstrated in Linux(Ununtu 20.04).

Setup

Prerequisite

• Install AFL++.

  sudo apt-get update
  sudo apt-get -y install afl++

• Install opam.

  apt-get update
  apt-get install ocaml opam

• Install AFL version of OCaml compiler.

  opam switch create afl411 4.11.2+afl
  eval $(opam env)

Build ReScript parser and prepare fuzzing inputs

• Clone this repo. You should clone with --recursive flag, as this repo includes ReScript parser as well as other ReScript projects for being used as fuzz seeds.

  git clone --recursive git@github.com:Sehun0819/fuzz-rescript-parser.git

• Build ReScript parser.

  cd fuzz-rescript-parser
  make parser

• Prepare seed pool(fuzzing inputs).

  make corpus

Fuzz ReScript parser

• Start fuzzing.

  make fuzz

  You will see an interface like below, which shows you fuzzing status.

• Fuzzed inputs can be found in ./fuzz_report/default/crashes/. Execute parser with found input to detect bugs. To trace a call stack, activate an OCaml flag.

  export OCAMLRUNPARAM=b
  ./syntax/_build/default/cli/res_cli.exe ./fuzz_report/default/crashes/<fuzzed input>