HistoryEdit

RUSTSEC-2022-0041

Unsoundness of AtomicCell<64> arithmetics on 32-bit targets that support Atomic64

Issued
Package
crossbeam-utils (crates.io)
Type
INFO Unsound
Categories
Aliases
Details
https://github.com/crossbeam-rs/crossbeam/pull/781
Patched
  • >=0.8.7

Description

Impact

Affected versions of this crate incorrectly assumed that the alignment of {i,u}64 was always the same as Atomic{I,U}64.

However, the alignment of {i,u}64 on a 32-bit target can be smaller than Atomic{I,U}64.

This can cause the following problems:

Crates using fetch_* methods with AtomicCell<{i,u}64> are affected by this issue.

32-bit targets without Atomic{I,U}64 and 64-bit targets are not affected by this issue.

32-bit targets with Atomic{I,U}64 and {i,u}64 have the same alignment are also not affected by this issue.

The following is a complete list of the builtin targets that may be affected. (last update: nightly-2022-02-11)

(script to get list)

Patches

This has been fixed in crossbeam-utils 0.8.7.

Affected 0.8.x releases have been yanked.

Thanks to @taiki-e