/unsafe-review

Interactive review session for unsafe Rust code.

Usage

/unsafe-review

Description

Starts an interactive review session that guides you through reviewing unsafe code using the unsafe-checker skill checklists.

Workflow

Identify unsafe code in the current file/selection
Load review checklist from unsafe-checker/checklists/review-unsafe.md
Step through each check:
- Ask clarifying questions
- Verify invariants
- Suggest improvements
Generate report with findings and recommendations

Interactive Prompts

The review will ask questions like:

Reviewing: unsafe { *ptr }

1. Is this pointer guaranteed non-null?
   - How is null prevented?
   - Show me the null check

2. Is the pointer properly aligned?
   - What type is it pointing to?
   - Where does the pointer come from?

3. Is the pointed-to memory valid?
   - Who allocated it?
   - Is it initialized?
   - How long is it valid?

4. Could this panic?
   - What happens if it panics here?
   - Is cleanup needed?

Checklist Categories

Surface-Level

SAFETY comments present and meaningful?
Safety documentation for unsafe fn?
Unsafe blocks minimized?

Memory Safety

Pointer validity (non-null, aligned, valid)
No aliasing violations
No use-after-free
No double-free
Bounds checking

Type Safety

Correct transmutes
Valid enum discriminants
Proper repr attributes

Concurrency

Send/Sync correctness
No data races
Proper synchronization

FFI

Type compatibility
Panic handling
Error handling
Memory ownership

Example Session

/unsafe-review

Scanning for unsafe code...
Found 2 unsafe blocks and 1 unsafe fn.

--- Review 1/3 ---
Location: src/buffer.rs:42
Code: unsafe { slice::from_raw_parts(self.ptr, self.len) }

[Checklist]
[ ] SAFETY comment present?
    > Yes: "// SAFETY: ptr and len are validated in new()"

[ ] Pointer non-null?
    > Checking... new() uses NonNull, so guaranteed

[ ] Pointer aligned?
    > Type is u8, alignment is 1, always aligned

[ ] Length valid?
    > len is set in new() and never changed

[Result] PASS - All checks satisfied

--- Review 2/3 ---
...

Output

After review completes:

=== Unsafe Review Summary ===

Total unsafe items: 3
- Passed: 2
- Warnings: 1
- Errors: 0

Warnings:
1. src/ffi.rs:87 - Missing catch_unwind in extern "C" fn

Recommendations:
- Add panic handling to FFI functions
- Consider using NonNull instead of raw pointers