In the Linux kernel, the following vulnerability has been resolved:
lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
Restore the SIMD usability check that was removed by commit 773426f4771b
("crypto: arm/poly1305 - Add block-only interface").
This safety check is cheap and is well worth eliminating a footgun.
While the Poly1305 functions should not be called when SIMD registers
are unusable, if they are anyway, they should just do the right thing
instead of corrupting random tasks' registers and/or computing incorrect
MACs. Fixing this is also needed for poly1305_kunit to pass.
Just use may_use_simd() instead of the original crypto_simd_usable(),
since poly1305_kunit won't rely on crypto_simd_disabled_for_test.
lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
Restore the SIMD usability check that was removed by commit 773426f4771b
("crypto: arm/poly1305 - Add block-only interface").
This safety check is cheap and is well worth eliminating a footgun.
While the Poly1305 functions should not be called when SIMD registers
are unusable, if they are anyway, they should just do the right thing
instead of corrupting random tasks' registers and/or computing incorrect
MACs. Fixing this is also needed for poly1305_kunit to pass.
Just use may_use_simd() instead of the original crypto_simd_usable(),
since poly1305_kunit won't rely on crypto_simd_disabled_for_test.
Metrics
Affected Vendors & Products
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Mon, 15 Sep 2025 13:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Description | In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts Restore the SIMD usability check that was removed by commit 773426f4771b ("crypto: arm/poly1305 - Add block-only interface"). This safety check is cheap and is well worth eliminating a footgun. While the Poly1305 functions should not be called when SIMD registers are unusable, if they are anyway, they should just do the right thing instead of corrupting random tasks' registers and/or computing incorrect MACs. Fixing this is also needed for poly1305_kunit to pass. Just use may_use_simd() instead of the original crypto_simd_usable(), since poly1305_kunit won't rely on crypto_simd_disabled_for_test. | |
Title | lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts | |
References |
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-09-15T12:36:44.792Z
Reserved: 2025-04-16T07:20:57.134Z
Link: CVE-2025-39802

No data.

Status : Received
Published: 2025-09-15T13:15:35.703
Modified: 2025-09-15T13:15:35.703
Link: CVE-2025-39802

No data.

No data.