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Fuzz Java with libFuzzer.

You need:

  • clang
  • gradle
  • libFuzzer-gv: Get libFuzzer-gv, build, and put libFuzzer.a in this project's root directory
  • Oracle JDK. Set the environment variable JAVA_HOME to the JDK installation directory.

Put your code in the run method in fuzzertarget/fuzzertarget/ Return true from this method to force a crash and write the offending input to disk (for example if a certain exception was thrown).

Set the environment variable JAVA_FUZZER_CLASSPATH to a colon-separated list of paths to JAR files to serve as dependencies.

Type CXX=clang++ make to build.

CXXFLAGS can be empty (you do NOT need to instrument the C++ files).

Run with:

./fuzzer -custom_guided=1 -no_coverage_guided=1 -rss_limit_mb=6000 <corpus directory>

You can run it with less than 6GB, but you then also need to alter the -Xmx4096m option in fuzzerentry.cpp (preferably to a value +/- 2GB lower than your rss_limit_mb).



to crash on very slow inputs.

This project uses portions of Kelinci by Rody Kersten.

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