These fuzz tests are designed to be included in Google's Adding a new fuzz test
Add the test name on a new line in fuzz_tests.txt.
In fuzzer.c, add a function to be run:
int $test_name (const char* data, size_t size) {
...
return 0;
}
And invoke it from LLVMFuzzerTestOneInput:
#if _Py_FUZZ_YES(fuzz_builtin_float) rv |= _run_fuzz(data, size, fuzz_builtin_float); #endif
LLVMFuzzerTestOneInput will run in oss-fuzz, with each test in
fuzz_tests.txt run separately.
Seed data (corpus) for the test can be provided in a subfolder called
<test_name>_corpus such as fuzz_json_loads_corpus. A wide variety
of good input samples allows the fuzzer to more easily explore a diverse
set of paths and provides a better base to find buggy input from.
Dictionaries of tokens (see oss-fuzz documentation for more details) can
be placed in the dictionaries folder with the name of the test.
For example, dictionaries/fuzz_json_loads.dict contains JSON tokens
to guide the fuzzer.
Libraries written in C that might handle untrusted data are worthwhile. The more complex the logic (e.g. parsing), the more likely this is to be a useful fuzz test. See the existing examples for reference, and refer to the /python_sourcecode/python3.8.1/tree/master/Modules/_xxtestfuzz