la-stack 0.4.6

Fast, stack-allocated linear algebra for fixed dimensions
Documentation
# Security Policy

## Supported Versions

Use the latest released crate version or the default branch. Security fixes
are not backported to older versions unless noted in a release.

This crate is pre-1.0 and under active development, so API compatibility and
security support are tied to the current release line.

## Reporting a Vulnerability

Please report vulnerabilities privately using GitHub private vulnerability
reporting:

<https://github.com/acgetchell/la-stack/security/advisories/new>

Do not open a public issue for suspected vulnerabilities.

Include:

- Affected crate version or commit.
- Enabled Cargo features, especially `exact` if exact arithmetic is involved.
- Steps to reproduce, ideally with a minimal Rust example or test.
- Expected and observed behavior.
- Security impact, such as a panic, denial of service, or incorrect result.
- Any relevant matrix, vector, or benchmark input shape, with sensitive data
  removed.
- A suggested fix or mitigation, if available.

For numerical correctness issues that are not security-sensitive, open a
normal GitHub issue with a minimal reproduction.

## Disclosure Process

- Reports are acknowledged as maintainer availability allows.
- The issue is triaged and its severity assessed on a best-effort basis.
- Accepted reports receive updates when there is meaningful progress or a
  material change in the assessment.
- For an accepted vulnerability, the project prepares a fix, publishes a
  GitHub Security Advisory, releases the fix, and requests a RustSec advisory
  when appropriate.
- If a report is declined, the reporter receives an explanation.

Please follow coordinated disclosure and avoid public disclosure until a fix
or mitigation is available.

## Scope

The crate uses `#![forbid(unsafe_code)]`, which reduces memory-safety risk.
Security-relevant correctness and availability issues can still exist. In
scope are:

- Panics or crashes triggered by malformed or adversarial matrices or vectors.
- CPU or memory denial of service caused by crafted inputs, including inputs
  to optional exact-arithmetic paths.
- Incorrect numerical results that affect security, data integrity, or
  availability when processing untrusted input.
- Violations of documented exact-arithmetic guarantees, such as silent
  precision loss, when they have a security impact.

Out of scope are:

- Documented floating-point limitations, conditioning behavior, or rounding
  bounds that do not create a security impact.
- Performance limitations that are not exploitable as denial of service.
- Issues caused by use outside the documented API contracts or supported
  problem scope.

## Patch and Advisory Policy

- Fixes are released on the latest supported release line. Older releases
  receive fixes only when explicitly noted.
- Releases are published to crates.io with corresponding GitHub releases.
- Accepted vulnerabilities are documented with GitHub Security Advisories and,
  when appropriate, RustSec advisories.
- Public technical detail may be limited until users have had a reasonable
  opportunity to update.

## RustSec

Applicable vulnerabilities may be disclosed through the
[RustSec Advisory Database](https://github.com/RustSec/advisory-db), enabling
detection with `cargo audit`.

## Safe Harbor

Good-faith security research is welcome. Avoid privacy violations, data
destruction, persistence, service disruption, and public disclosure before a
fix or mitigation is available. Reports that follow coordinated disclosure
and make a reasonable effort to avoid harm are treated as helpful
contributions.

## Acknowledgements

Responsible disclosure is appreciated. Reporters may be credited in
advisories or release notes unless anonymity is requested.

## Security Checks

This project uses GitHub CodeQL, Dependabot security updates, secret scanning
with push protection, `cargo audit`, zizmor, Clippy SARIF analysis, and
repository-owned Semgrep rules.

### Numerical logging false positives

CodeQL's `rust/cleartext-logging` query uses name-based heuristics to identify
potentially sensitive data. Here, `Matrix::certified_error_bound` and the
benchmark helper's `certified_bound` refer to numerical rounding-error bounds.
They contain no credentials, cryptographic certificates, or personal information.

Alerts #171–#178 were reviewed against commit
`bd80cc05df3ebf409d8db9a471b671a5737bf0c4`: their sinks are assertion or panic
diagnostics for deterministic test and benchmark fixtures. These individual
alerts were dismissed as false positives with that rationale. Keep the query
enabled and preserve diagnostic values needed to investigate numerical failures.
Review new alerts on their own data flow.

### Benchmark dependency maintenance

As of September 7, 2026, `paste` 1.0.15 enters through the development dependency
`faer` 0.24.4, via `gemm` 0.19.0 and `pulp` 0.22.3. Those are the latest
published upstream versions checked on that date. Repository-owned Rust code
already uses `pastey`; changing that direct dependency cannot replace upstream
uses of `paste`.

[RUSTSEC-2024-0436](https://rustsec.org/advisories/RUSTSEC-2024-0436.html) is an
unmaintained-package advisory with no patched version. It is a genuine
maintenance concern, separate from the logging false positives. `paste` is absent
from the library's normal and build dependency graph, including with `exact`
enabled, but its procedural macro executes when building development targets.

Keep this advisory visible in `cargo audit`. Recheck the dependency path with
`cargo tree --locked --all-features -i paste` when updating `faer`, `gemm`, or
`pulp`, and remove the dependency through a maintained upstream release when
available.