TestingOSSFuzz.md

Testing OSS-Fuzz

ASTC-Encoder has been integrated into the Google OSS-Fuzz program, which performs API fuzz testing on a Google-hosted CI infrastructure.

This page is a set of summary instructions explaining how to locally reproduce failures reported by OSS-Fuzz on a Linux machine. Full documentation is provided by the OSS-Fuzz project documentation pages.

Prerequisites

Install Docker:

sudo apt  install docker.io
sudo usermod -aG docker $USER

You will need to log out and log in again for the group changes to take effect.

Running Python-based CLI functional tests

Checkout the OSS-Fuzz project:

git clone --depth=1 https://github.com/google/oss-fuzz.git
cd oss-fuzz

Download the standard Docker images with the tools pre-integrated:

python3 infra/helper.py pull_images

Build the Docker image and the fuzzers for astcenc.

Note

Fuzzers are built for a specific sanitizer, so you will need to build and run the fuzzers multiple times if you want coverage of both ASAN and UBSAN.

python3 infra/helper.py build_image astc-encoder

# Build using clean checkout in the container
python3 infra/helper.py build_fuzzers astc-encoder

# Build using local checkout mounted into the container
python3 infra/helper.py build_fuzzers astc-encoder /mnt/c/work/projects/astcenc/Source --sanitizer <address,undefined, etc>

Run a reproducer testcase downloaded from OSS Fuzz:

python3 infra/helper.py reproduce astc-encoder <fuzz_target> <testcase>

Sometimes reproducers are intermittent and do not always reproduce. Running the the test scenario in a loop can be a useful way to try and make it reproduce.

while python3 infra/helper.py reproduce astc-encoder <fuzz_target> <testcase>; do :; done

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