qa-assets

Bitcoin Core related blobs used for quality assurance.

Fuzz inputs

qa-assets/fuzz_seed_corpus contains one input corpus per fuzz target (one folder per target named the same as each target).

Contributing inputs

For documentation on how to fuzz Bitcoin Core please see fuzzing.md.

If you want to contribute fuzz inputs, please "merge" the inputs before submitting a pull request. You can use the libFuzzer option -set_cover_merge=1 (recommended with -use_value_profile=0) or the --m_dir option of the fuzz runner: test_runner.py.

Pruning inputs

• Over time fuzz engines reduce inputs (produce a smaller input that yields the same coverage statistics), which causes our corpora to accumulate larger non-reduced inputs.
• Code changes can lead to inputs losing their coverage.

To avoid corpora bloat, stale inputs and potential CI timeouts, we usually prune/minimize our corpora around the branch-off point using the delete_nonreduced_fuzz_inputs.sh script (Recommended to run in a fresh VM, see documentation in the script). The script is usually run twice to ensure that the results are "somewhat" reproducible (e.g. https://github.com/bitcoin-core/qa-assets/pull/119#issuecomment-1518019457).

After pruning the corpora, the coverage should not have dropped at all.

Pulling inputs from oss-fuzz

Use download_oss_fuzz_inputs.py to pull fuzz inputs from oss-fuzz.