# How to contribute to syzkaller

## Guidelines

If you want to contribute to the project, feel free to send a pull request.

Before sending a pull request you need to [sign Google CLA](https://cla.developers.google.com/)
(if you don't a bot will ask you to do that) and add yourself to
[AUTHORS](/AUTHORS)/[CONTRIBUTORS](/CONTRIBUTORS) files (in case this is your
first pull request to syzkaller).

Some guildelines to follow:

- Commit messages should follow the following template:
```
dir/path: one-line description
<empty line>
Extended multi-line description that includes
the problem you are solving and how it is solved.
```
`dir/path` is a relative path to the main dir this commit changes
(look at examples in the [commit history](https://github.com/google/syzkaller/commits/master)).\
Please pay attention to punctuation. In particular:
- `one-line description` does *not* start with a Capital letter.
- there is *no dot* at the end of `one-line description`.
- `Extended multi-line description` is full English sentenses with Capital letters and dots.

Also:
- If you commit fixes an issue, please include `Fixes #NNN` line into commit message
(where `NNN` is issue number). This will auto-close the issue. If you need to mention
an issue without closing it, add `Update #NNN`.
- The pull request text is mostly irrelevant.
- Run `make presubmit` and ensure that it passes before sending a PR.
  It may require some additional packages to be installed (try `sudo make install_prerequisites`).
- `*.const` files are checked-in with the `*.txt` changes in the same commit.
- Rebase your pull request onto the master branch before submitting.
- If you're asked to add some fixes to your pull requested, please squash the new commits with the old ones.

## What to work on

Extending/improving [system call descriptions](syscall_descriptions.md) is always a good idea.

Unassigned issues from the [bug tracker](https://github.com/google/syzkaller/issues) are worth doing, but some of them might be complicated.

If you want to contribute code or syscall descriptions, at the very least you need to be able to build and run syzkaller, see the instructions [here](/docs/setup.md).

If you want to work on something non-trivial, please briefly describe it on the [syzkaller@googlegroups.com](https://groups.google.com/forum/#!forum/syzkaller) mailing list first,
so that there is agreement on high level approach and no duplication of work between contributors.

## How to create a pull request

- First, you need an own git fork of syzkaller repository. Nagivate to
[github.com/google/syzkaller](https://github.com/google/syzkaller) and press `Fork` button in the top-right corner of
the page. This will create `https://github.com/YOUR_GITHUB_USERNAME/syzkaller` repository.

- Checkout main syzkaller repository if you have not already. To work with `go` command the checkout must be under
`$GOPATH`. The simplest way to do it is to run `go get -u -d github.com/google/syzkaller/prog`, this will checkout
the repository in `$GOPATH/src/github.com/google/syzkaller`.
- Remember to `export PATH=$GOPATH/bin:$PATH` if you have not already.
- Then add your repository as an additional origin:

```shell
cd $GOPATH/src/github.com/google/syzkaller
git remote add my-origin https://github.com/YOUR_GITHUB_USERNAME/syzkaller.git
git fetch my-origin
git checkout -b my-branch my-origin/master
```

This adds git origin `my-origin` with your repository and checks out new branch `my-branch` based on `master` branch.

- Change/add files as necessary.
- Commit changes locally. For this you need to run `git add` for all changed files, e.g. `git add sys/linux/sys.txt`. You can run `git status` to see what files were changed/created. When all files are added (`git status` shows no files in `Changes not staged for commit` section and no relevant files in `Untracked files` section), run `git commit` and enter commit description in your editor.
- Run tests locally (`make install_prerequisites` followed by `make presubmit`).
- Push the commit to your fork on github with `git push my-origin my-branch`.
- Nagivate to [github.com/google/syzkaller](https://github.com/google/syzkaller) and you should see green `Compare & pull request` button, press it. Then press `Create pull request`. Now your pull request should show up on [pull requests page](https://github.com/google/syzkaller/pulls).
- If you don't see `Create pull request` button for any reason, you can create pull request manually. For that nagivate to [pull requests page](https://github.com/google/syzkaller/pulls), press `New pull request`, then `compare across forks` and choose `google/syzkaller`/`master` as base and `YOUR_GITHUB_USERNAME/syzkaller`/`my-branch` as compare and press `Create pull request`.
- If you decided to rebase commits in `my-branch` (e.g. to rebase them onto updated master) after you created a pull-request, you will need to do a force push: `git push -f my-origin my-branch`.