[v2] arm64/fpsimd: Fix use after free in SME when changing SVE VL

[PATCH v2 0/3] arm64/fpsimd: Fix use after free in SME when changing SVE VL

Posted by Mark Brown 2 years, 5 months ago

This series fixes an issue which David Spickett found where if we change
the SVE VL while SME is in use we can end up attempting to save state to
an unallocated buffer and adds testing coverage for that plus a bit more
coverage of VL changes, just for paranioa.

Signed-off-by: Mark Brown <broonie@kernel.org>
---
Changes in v2:
- Always reallocate the SVE state.
- Rebase onto v6.5-rc2.
- Link to v1: https://lore.kernel.org/r/20230713-arm64-fix-sve-sme-vl-change-v1-0-129dd8611413@kernel.org

---
Mark Brown (3):
      arm64/fpsimd: Ensure SME storage is allocated after SVE VL changes
      kselftest/arm64: Add a test case for SVE VL changes with SME active
      kselftest/arm64: Validate that changing one VL type does not affect another

 arch/arm64/kernel/fpsimd.c                    |  33 +++++--
 tools/testing/selftests/arm64/fp/vec-syscfg.c | 127 +++++++++++++++++++++++++-
 2 files changed, 148 insertions(+), 12 deletions(-)
---
base-commit: 06785562d1b99ff6dc1cd0af54be5e3ff999dc02
change-id: 20230713-arm64-fix-sve-sme-vl-change-60eb1fa6a707

Best regards,
-- 
Mark Brown <broonie@kernel.org>

Re: [PATCH v2 0/3] arm64/fpsimd: Fix use after free in SME when changing SVE VL

Posted by Will Deacon 2 years, 4 months ago

On Thu, 20 Jul 2023 19:38:57 +0100, Mark Brown wrote:
> This series fixes an issue which David Spickett found where if we change
> the SVE VL while SME is in use we can end up attempting to save state to
> an unallocated buffer and adds testing coverage for that plus a bit more
> coverage of VL changes, just for paranioa.
> 
> 

Applied to arm64 (for-next/selftests), thanks!

[1/3] arm64/fpsimd: Ensure SME storage is allocated after SVE VL changes
      https://git.kernel.org/arm64/c/d4d5be94a878
[2/3] kselftest/arm64: Add a test case for SVE VL changes with SME active
      https://git.kernel.org/arm64/c/0c7c237b1c35
[3/3] kselftest/arm64: Validate that changing one VL type does not affect another
      https://git.kernel.org/arm64/c/0aeead9bb240

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev

Re: [PATCH v2 0/3] arm64/fpsimd: Fix use after free in SME when changing SVE VL

Posted by Will Deacon 2 years, 5 months ago

On Thu, 20 Jul 2023 19:38:57 +0100, Mark Brown wrote:
> This series fixes an issue which David Spickett found where if we change
> the SVE VL while SME is in use we can end up attempting to save state to
> an unallocated buffer and adds testing coverage for that plus a bit more
> coverage of VL changes, just for paranioa.
> 
> 

Applied first patch to arm64 (for-next/fixes), thanks!

[1/3] arm64/fpsimd: Ensure SME storage is allocated after SVE VL changes
      https://git.kernel.org/arm64/c/d4d5be94a878

I'll look at the selftests stuff for 6.6 when I get to that (probably
next week).

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev