Lib.rs

Unsafe code in ObjectPool has time-of-check to time-of-use (TOCTOU) bug that can eventually lead to a memory safety violation. ObjectPool and HandlePool implicitly assumes that HandleLike trait methods are pure, i.e., they always return the same value. However, this assumption is unsound since HandleLike is a safe, public trait that allows a custom implementation.

CVE-2020-35889

GHSA-m833-jv95-mfjh

As of version 0.6.0, the ObjectPool explicitly creates an uninitialized instance of its type parameter when it attempts to free an object, and swaps it into the storage. This causes instant undefined behavior due to reading the uninitialized memory in order to write it to the pool storage.

Extremely basic usage of the crate can trigger this issue, e.g. this code from a doctest:

use crayon::prelude::*;
application::oneshot().unwrap();

let mut params = MeshParams::default();

let mesh = video::create_mesh(params, None).unwrap();

// Deletes the mesh object.
video::delete_mesh(mesh); // <-- UB

The Clippy warning for this code was silenced in commit c2fde19caf6149d91faa504263f0bc5cafc35de5.

Discovered via https://asan.saethlin.dev/ub?crate=crayon&version=0.7.1

GHSA-xfhw-6mc4-mgxf