- Reported
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- Issued
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- Package
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crossbeam-utils
(crates.io)
- Type
-
INFO
Unsound
- Categories
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- Aliases
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- References
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- Patched
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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:
- Unaligned memory accesses
- Data race
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)
- armv7-apple-ios (tier 3)
- armv7s-apple-ios (tier 3)
- i386-apple-ios (tier 3)
- i586-unknown-linux-gnu
- i586-unknown-linux-musl
- i686-apple-darwin (tier 3)
- i686-linux-android
- i686-unknown-freebsd
- i686-unknown-haiku (tier 3)
- i686-unknown-linux-gnu
- i686-unknown-linux-musl
- i686-unknown-netbsd (tier 3)
- i686-unknown-openbsd (tier 3)
- i686-wrs-vxworks (tier 3)
(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
Advisory available under CC0-1.0
license.