| Index: test/fuzzer/README.md
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| diff --git a/test/fuzzer/README.md b/test/fuzzer/README.md
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| index 7b2955c5a5c6c04a0eed3142c4aa8e8c43bd6706..ed0ce1fa2a17d5cd8c4f0fb6233d405f0fe829cc 100644
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| --- a/test/fuzzer/README.md
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| +++ b/test/fuzzer/README.md
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| @@ -1,34 +1,91 @@
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| # How to make a libFuzzer fuzzer in V8
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|
|
| -This document describes how to make a new libfuzzer fuzzer for V8. A general introduction to libfuzzer can be found at [here](https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/README.md). In short, libFuzzer is an in-process coverage-driven evolutionary fuzzer. libFuzzer serves you with a sequence of byte arrays that you can use to test your code. libFuzzer tries to generate this sequence of byte arrays in a way that maximizes test coverage.
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| +This document describes how to make a new libFuzzer fuzzer for V8. A general
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| +introduction to libFuzzer can be found
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| +[here](https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/README.md).
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| +In short, libFuzzer is an in-process coverage-driven evolutionary fuzzer.
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| +libFuzzer serves you with a sequence of byte arrays that you can use to test
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| +your code. libFuzzer tries to generate this sequence of byte arrays in a way
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| +that maximizes test coverage.
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|
|
| **Warning**: By itself libFuzzer typically does not generate valid JavaScript code.
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|
|
| ## Changes to V8
|
|
|
| -**tldr:** Do the same as https://codereview.chromium.org/2280623002 to introduce a new fuzzer to V8.
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| -This is a step by step guide on how to make a new fuzzer in V8. In the example the fuzzer is called `foo`.
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| -1) Copy one of the existing fuzzer implementations in [test/fuzzer/](https://cs.chromium.org/chromium/src/v8/test/fuzzer/), e.g. `cp wasm.cc foo.cc`
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| - * Copying an existing fuzzer is a good idea to get all the required setup, e.g. setting up the isolate
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| -2) Create a directory called `foo` in [test/fuzzer/](https://cs.chromium.org/chromium/src/v8/test/fuzzer/) which contains at least one file
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| - * The file is used by the trybots to check whether the fuzzer actually compiles and runs
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| -3) Copy the build rules of an existing fuzzer in [BUILD.gn](https://cs.chromium.org/chromium/src/v8/BUILD.gn), e.g. the build rules for the [wasm.cc](https://cs.chromium.org/chromium/src/v8/test/fuzzer/wasm.cc) fuzzer are `v8_source_set("wasm_fuzzer")` and `v8_fuzzer("wasm_fuzzer")`. Note that the name has to be the name of the
|
| -directory created in Step 2 + “_fuzzer” so that the scripts on the trybots work
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| -4) Now you can already compile the fuzzer with `ninja -j 1000 -C out/tmp/v8_simple_foo_fuzzer`
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| - * Use this binary to reproduce issues found by cluster fuzz, e.g. `out/tmp/v8_simple_foo_fuzzer testcase.foo`
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| -5) Copy the build rules of an existing fuzzer in [test/fuzzer/fuzzer.gyp](https://cs.chromium.org/chromium/src/v8/test/fuzzer/fuzzer.gyp), e.g. the build rules for the [wasm.cc](https://cs.chromium.org/chromium/src/v8/test/fuzzer/wasm.cc) fuzzer are `v8_simple_wasm_fuzzer` and `wasm_fuzzer_lib`
|
| +**tldr:** Do the same as https://codereview.chromium.org/2280623002 to introduce
|
| +a new fuzzer to V8.
|
| +
|
| +This is a step by step guide on how to make a new fuzzer in V8. In the example
|
| +the fuzzer is called `foo`.
|
| +
|
| +1. Copy one of the existing fuzzer implementations in
|
| + [test/fuzzer/](https://cs.chromium.org/chromium/src/v8/test/fuzzer/), e.g. `cp wasm.cc foo.cc`
|
| +
|
| + * Copying an existing fuzzer is a good idea to get all the required setup,
|
| + e.g. setting up the isolate
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| +
|
| +2. Create a directory called `foo` in
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| + [test/fuzzer/](https://cs.chromium.org/chromium/src/v8/test/fuzzer/) which
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| + contains at least one file
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| +
|
| + * The file is used by the trybots to check whether the fuzzer actually
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| + compiles and runs
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| +
|
| +3. Copy the build rules of an existing fuzzer in
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| + [BUILD.gn](https://cs.chromium.org/chromium/src/v8/BUILD.gn), e.g. the build
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| + rules for the
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| + [wasm.cc](https://cs.chromium.org/chromium/src/v8/test/fuzzer/wasm.cc) fuzzer
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| + are `v8_source_set("wasm_fuzzer")` and `v8_fuzzer("wasm_fuzzer")`. Note that
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| + the name has to be the name of the directory created in Step 2 + `_fuzzer` so
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| + that the scripts on the trybots work
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| +
|
| +4. Now you can already compile the fuzzer, e.g. with `ninja -j 1000 -C
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| + out/x64.debug/v8_simple_foo_fuzzer`
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| +
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| + * Use this binary to reproduce issues found by cluster fuzz, e.g.
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| + `out/x64.debug/v8_simple_foo_fuzzer testcase.foo`
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| +
|
| +5. Copy the build rules of an existing fuzzer in
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| + [test/fuzzer/fuzzer.gyp](https://cs.chromium.org/chromium/src/v8/test/fuzzer/fuzzer.gyp),
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| + e.g. the build rules for the
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| + [wasm.cc](https://cs.chromium.org/chromium/src/v8/test/fuzzer/wasm.cc) fuzzer
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| + are `v8_simple_wasm_fuzzer` and `wasm_fuzzer_lib`
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| +
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| * This build rule is needed to compile with gyp
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| -6) Copy the binary name and the test directory name in [test/fuzzer/fuzzer.isolate](https://cs.chromium.org/chromium/src/v8/test/fuzzer/fuzzer.isolate)
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| -7) Add the fuzzer to the FuzzerTestSuite in [test/fuzzer/testcfg.py](https://cs.chromium.org/chromium/src/v8/test/fuzzer/testcfg.py)
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| - * This step is needed to run the fuzzer with the files created in Step 2 on the trybots
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| -8) Commit the changes described above to the V8 repository
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| +
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| +6. Copy the binary name and the test directory name in
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| + [test/fuzzer/fuzzer.isolate](https://cs.chromium.org/chromium/src/v8/test/fuzzer/fuzzer.isolate)
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| +
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| +7. Add the fuzzer to the FuzzerTestSuite in
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| + [test/fuzzer/testcfg.py](https://cs.chromium.org/chromium/src/v8/test/fuzzer/testcfg.py)
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| +
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| + * This step is needed to run the fuzzer with the files created in Step 2 on
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| + the trybots
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| +
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| +8. Commit the changes described above to the V8 repository
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|
|
| ## Changes to Chromium
|
| -**tldr:** Do the same as https://codereview.chromium.org/2344823002 to add the new fuzzer to cluster fuzz.
|
| -1) Copy the build rules of an existing fuzzer in [testing/libfuzzer/fuzzers/BUILD.gn](https://cs.chromium.org/chromium/src/testing/libfuzzer/fuzzers/BUILD.gn), e.g. the build rule for the [wasm.cc](https://cs.chromium.org/chromium/src/v8/test/fuzzer/wasm.cc) fuzzer is {v8_wasm_fuzzer}. There is no need to set a dictionary , or a seed_corpus. See [chromium-fuzzing-getting-started](https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/getting_started.md) for more information.
|
| -2) Compile the fuzzer in chromium (for different configurations see: https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reproducing.md):
|
| +
|
| +**tldr:** Do the same as https://codereview.chromium.org/2344823002 to add the
|
| +new fuzzer to cluster fuzz.
|
| +
|
| +1. Copy the build rules of an existing fuzzer in
|
| + [testing/libfuzzer/fuzzers/BUILD.gn](https://cs.chromium.org/chromium/src/testing/libfuzzer/fuzzers/BUILD.gn),
|
| + e.g. the build rule for the
|
| + [wasm.cc](https://cs.chromium.org/chromium/src/v8/test/fuzzer/wasm.cc) fuzzer
|
| + is `v8_wasm_fuzzer`. There is no need to set a `dictionary` , or a `seed_corpus`.
|
| + See
|
| + [chromium-fuzzing-getting-started](https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/getting_started.md)
|
| + for more information.
|
| +
|
| +2. Compile the fuzzer in chromium (for different configurations see:
|
| + https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reproducing.md):
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| +
|
| * `gn gen out/libfuzzer '--args=use_libfuzzer=true is_asan=true is_debug=false enable_nacl=false'`
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| +
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| * `ninja -j 1000 -C out/libfuzzer/ v8_foo_fuzzer`
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| -3) Run the fuzzer locally
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| +
|
| +3. Run the fuzzer locally
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| +
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| * `mkdir /tmp/empty_corpus && out/libfuzzer/v8_foo_fuzzer /tmp/empty_corpus`
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|
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|