Advisories for Cargo/Nanorand package

TlsWyRand's implementation of Deref unconditionally dereferences a raw pointer, and returns multiple mutable references to the same object, which is undefined behavior.

An issue was discovered in the nanorand crate before 0.6.1 for Rust. There can be multiple mutable references to the same object because the TlsWyRand Deref implementation dereferences a raw pointer.

In versions of nanorand prior to 0.5.1, RandomGen implementations for standard unsigned integers could fail to properly generate numbers, due to using bit-shifting to truncate a 64-bit number, rather than just an as conversion. This often manifested as RNGs returning nothing but 0, including the cryptographically secure ChaCha random number generator.