quickjs-done/fuzz
Renáta Hodován 01454caf78
OSS-Fuzz targets improvements (#267)
* Move fuzz target sources from the oss-fuzz repository here

* Add support to build libFuzzer targets
* Simplify the fuzz_eval and fuzz_compile targets

The use of JS_NewContext instead of JS_NewContextRaw spares to call
JS_AddIntrinsic<XYZ> functions from the fuzz target, since the public
JS_NewContext API does exactly the same.

* Simplify the fuzz_regexp target

fuzz_regexp doesn't need to be dependant on libquickjs since the
runtime and the context - that were provided by libquickjs - were
only created to call two simple functions implemented in libquickjs
which could be mimicked by the fuzzer.
The removal of runtime and context objects implicated further
simplifications, like the omission of their one-time creation.
Finally, writing the result of the regexp operations into a file
is also superfluous, since it's not used by anybody.

* Recreate and destroy JS runtime and context in fuzz_eval and fuzz_compile targets

Before this patch, the test executions were not independent,
since all the executed tests used the same JavaScript runtime and
context, causing irreproducible failure reports.

* Enable bignumber support in eval and compile targets

Big numbers are used by the input corpus, but the targets were not
able to interpret them since they were not compiled into them.
This change improved the inital coverage of the fuzz_eval target with
21% and the coverage of the fuzz_compile target with 25% when using
the official corpus.

* Ensure std and os modules are available in the fuzz_eval and fuzz_compile targets
* Add fuzzer dictionary with builtin and variable names. Furthermore, added a JS script that collects all the builtin
names from the executing engine. 
* Move common fuzzer code into one place
* Enable to define the LIB_FUZZING_ENGINE variable to ease the oss-fuzz integration
* Add README to fuzzers
2024-05-08 18:19:48 +02:00
..
fuzz.dict OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00
fuzz_common.h OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00
fuzz_compile.c OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00
fuzz_eval.c OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00
fuzz_regexp.c OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00
generate_dict.js OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00
README OSS-Fuzz targets improvements (#267) 2024-05-08 18:19:48 +02:00

libFuzzer support for QuickJS
=============================

Build QuickJS with libFuzzer support as follows:

  CONFIG_CLANG=y make libfuzzer

This can be extended with sanitizer support to improve efficacy:

  CONFIG_CLANG=y CONFIG_ASAN=y make libfuzzer


Currently, there are three fuzzing targets defined: fuzz_eval, fuzz_compile and fuzz_regexp.
The above build command will produce an executable binary for each of them, which can be
simply executed as:

  ./fuzz_eval

or with an initial corpus:

  ./fuzz_compile corpus_dir/

or with a predefined dictionary to improve its efficacy:

  ./fuzz_eval -dict fuzz/fuzz.dict

or with arbitrary CLI arguments provided by libFuzzer (https://llvm.org/docs/LibFuzzer.html).