bpflint
Linting functionality for BPF C kernel programs. The Linux kernel's BPF sub-system is continuously being improved and certain patterns recommended in the past may no longer be state-of-the-art today. Similarly, some "foot guns" exist that by definition may not be obvious to new comers.
bpflint contains a linter for BPF C kernel programs that accepts
such a .bpf.c file as input and scans it for such known issues,
pointing them out and providing recommendations on how to fix them.
Provided is a Rust library, a command line interface, a Web UI, as well as a GitHub Action for linting of BPF C programs.
📚 Frequently Asked Questions (FAQ)
❓ Q: Why are there so few lints?
A: This repository provides basic infrastructure components to build on, but we hope for contributions from the community for best practices and how to formalize them.
❓ Q: I am interested in helping out. How can I get started?
A: We have a list of issues with ideas for contributions, which mark a good starting point. For documentation on lints specifically and how to add a new one, please check out the lints/ sub-directory. All other questions are probably best asked in one of the existing issues (or a new one).
❓ Q: I have a repository with BPF code, can I lint contributions easily?
A: If you are using GitHub Actions as the continuous integration
solution of choice, you can add a separate job using the
lint-bpf Action.
For other CI systems some manual plumbing will be necessary. We
provide statically linked bpflinter CLI binaries that can be
downloaded from each cli-vX.Y.Z release and used directly on
any Linux. E.g.,
https://github.com/d-e-s-o/bpflint/releases/download/cli-v0.1.2/bpflinter-x86_64-unknown-linux-musl
❓ Q: I got a false-positive, what can I do?
A: Some lints require context that is not possible or feasible for
the linter to acquire. E.g., kprobe attach point usage may be
flagged as being an unstable attach point, but the linter cannot
know whether a better alternative, say, in the form of a
tracepoint, exists. bpflint recognizes C comments of the
following form on blocks and statements:
/* bpflint: disable=<lint-name> */
When encountered, the named lint will be disabled for the
directly following item (block, statement, ...).