In order to use create a rustix backend for the getrandom crate that would pass its tests using memory sanitizer, these functions nedd to __msan_unpoison their output buffer only when they succeed, when #[cfg(sanitize = "memory")] (only available on Nightly):
rand::getrandom_uninit
- ,io::read
rand::getrandom_uninit is the most urgent, as people probably won't be running memory sanitizer on a kernel so old that getrandom would fall back to reading from /dev/urandom.
See rust-random/getrandom#463 for my attempt to do this directly within getrandom.