Fix copy arguments for strict aligned architectures

[haesbaert]

Proposed commit message

Fix copy arguments for strict aligned architectures

Small typo on copy arguments. In practice only affects arm32 and arm64 as I doubt there are users
of other architectures around.

Without this fix, Auditbeat would incorrectly decode ktrace events in non i386/amd64.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

[mergify]

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[mergify]

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git fetch upstream
git checkout -b copy-args upstream/copy-args
git merge upstream/main
git push upstream copy-args

[efd6]

This can be brought into the modern era and have error handling added if it is

func copyInt(dst unsafe.Pointer, src unsafe.Pointer, len uint8) error {
	switch len {
	case 1, 2, 4, 8:
		copy(unsafe.Slice((*byte)(dst), len), unsafe.Slice((*byte)(src), len))
		return nil
	default:
		return errBadSize
	}
}

(we can also remove the array punning below by changing the preamble in readInt to asSlice := unsafe.Slice((*byte)(ptr), len).

[haesbaert]

That's great, but can we do this in a second future step? I've found this just by reading the code and don't have a proper setup in place to test more invasive changes.

[efd6]

Yeah, fair enough.