RUSTSEC-2025-0023

Broadcast channel calls clone in parallel, but does not require Sync

Reported

April 7, 2025

Issued

April 7, 2025 (last modified: April 8, 2025)

Package

tokio (crates.io)

Type

INFO Unsound

Categories

memory-corruption

References

https://github.com/tokio-rs/tokio/pull/7232

Patched

>=1.38.2, <1.39.0
>=1.42.1, <1.43.0
>=1.43.1, <1.44.0
>=1.44.2

Unaffected

<0.2.5

Description

The broadcast channel internally calls clone on the stored value when receiving it, and only requires T:Send. This means that using the broadcast channel with values that are Send but not Sync can trigger unsoundness if the clone implementation makes use of the value being !Sync.

Thank you to Austin Bonander for finding and reporting this issue.

Advisory available under CC0-1.0 license.