Resolve ARM kCFI build failure in idpf xsk.c

[PATCH 0/3] Resolve ARM kCFI build failure in idpf xsk.c

Posted by Nathan Chancellor 3 months, 2 weeks ago

Hi all,

This series resolves a build failure that is seen in
drivers/net/ethernet/intel/idpf/xsk.c after commit 9705d6552f58 ("idpf:
implement Rx path for AF_XDP") in 6.18-rc1 with ARCH=arm and
CONFIG_CFI=y. See patch 3 for a simplified reproducer on top of
defconfig.

I think this could go via hardening or net.

---
Nathan Chancellor (3):
      compiler_types: Introduce __nocfi_generic
      ARM: Select ARCH_USES_CFI_GENERIC_LLVM_PASS
      libeth: xdp: Disable generic kCFI pass for libeth_xdp_tx_xmit_bulk()

 arch/Kconfig                   | 7 +++++++
 arch/arm/Kconfig               | 2 ++
 include/linux/compiler_types.h | 6 ++++++
 include/net/libeth/xdp.h       | 2 +-
 4 files changed, 16 insertions(+), 1 deletion(-)
---
base-commit: 211ddde0823f1442e4ad052a2f30f050145ccada
change-id: 20251025-idpf-fix-arm-kcfi-build-error-65ae59616374

Best regards,
--  
Nathan Chancellor <nathan@kernel.org>

Re: [PATCH 0/3] Resolve ARM kCFI build failure in idpf xsk.c

Posted by Kees Cook 3 months, 1 week ago

On Sat, 25 Oct 2025 21:53:17 +0100, Nathan Chancellor wrote:
> This series resolves a build failure that is seen in
> drivers/net/ethernet/intel/idpf/xsk.c after commit 9705d6552f58 ("idpf:
> implement Rx path for AF_XDP") in 6.18-rc1 with ARCH=arm and
> CONFIG_CFI=y. See patch 3 for a simplified reproducer on top of
> defconfig.
> 
> I think this could go via hardening or net.
> 
> [...]

Applied to for-linus/hardening, thanks!

[1/3] compiler_types: Introduce __nocfi_generic
      https://git.kernel.org/kees/c/39c89ee6e9c4
[2/3] ARM: Select ARCH_USES_CFI_GENERIC_LLVM_PASS
      https://git.kernel.org/kees/c/1ed9e6b1004f
[3/3] libeth: xdp: Disable generic kCFI pass for libeth_xdp_tx_xmit_bulk()
      https://git.kernel.org/kees/c/c57f5fee54df

Take care,

-- 
Kees Cook