[PATCH] crypto: arm/crc32 - add kCFI annotations to asm routines

[PATCH] crypto: arm/crc32 - add kCFI annotations to asm routines

[Ard Biesheuvel]

From: Ard Biesheuvel <ardb@kernel.org>

The crc32/crc32c implementations using the scalar CRC32 instructions are
accessed via indirect calls, and so they must be annotated with type ids
in order to execute correctly when kCFI is enabled.

Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/arm/crypto/crc32-ce-core.S | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/arm/crypto/crc32-ce-core.S b/arch/arm/crypto/crc32-ce-core.S
index 3f13a76b9066..88f9edf94e95 100644
--- a/arch/arm/crypto/crc32-ce-core.S
+++ b/arch/arm/crypto/crc32-ce-core.S
@@ -48,6 +48,7 @@
  */
 
 #include <linux/linkage.h>
+#include <linux/cfi_types.h>
 #include <asm/assembler.h>
 
 	.text
@@ -123,11 +124,12 @@
 	 * uint crc32_pmull_le(unsigned char const *buffer,
 	 *                     size_t len, uint crc32)
 	 */
-ENTRY(crc32_pmull_le)
+SYM_FUNC_START(crc32_pmull_le)
 	adr		r3, .Lcrc32_constants
 	b		0f
+SYM_FUNC_END(crc32_pmull_le)
 
-ENTRY(crc32c_pmull_le)
+SYM_FUNC_START(crc32c_pmull_le)
 	adr		r3, .Lcrc32c_constants
 
 0:	bic		LEN, LEN, #15
@@ -236,8 +238,7 @@ fold_64:
 	vmov		r0, s5
 
 	bx		lr
-ENDPROC(crc32_pmull_le)
-ENDPROC(crc32c_pmull_le)
+SYM_FUNC_END(crc32c_pmull_le)
 
 	.macro		__crc32, c
 	subs		ip, r2, #8
@@ -296,11 +297,11 @@ ARM_BE8(rev16		r3, r3		)
 	.endm
 
 	.align		5
-ENTRY(crc32_armv8_le)
+SYM_TYPED_FUNC_START(crc32_armv8_le)
 	__crc32
-ENDPROC(crc32_armv8_le)
+SYM_FUNC_END(crc32_armv8_le)
 
 	.align		5
-ENTRY(crc32c_armv8_le)
+SYM_TYPED_FUNC_START(crc32c_armv8_le)
 	__crc32		c
-ENDPROC(crc32c_armv8_le)
+SYM_FUNC_END(crc32c_armv8_le)
-- 
2.45.2.505.gda0bf45e8d-goog

Re: [PATCH] crypto: arm/crc32 - add kCFI annotations to asm routines

[Kees Cook]

On Mon, Jun 10, 2024 at 05:26:39PM +0200, Ard Biesheuvel wrote:
> From: Ard Biesheuvel <ardb@kernel.org>
> 
> The crc32/crc32c implementations using the scalar CRC32 instructions are
> accessed via indirect calls, and so they must be annotated with type ids
> in order to execute correctly when kCFI is enabled.
> 
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Reviewed-by: Kees Cook <kees@kernel.org>

-- 
Kees Cook

Re: [PATCH] crypto: arm/crc32 - add kCFI annotations to asm routines

[Linus Walleij]

On Mon, Jun 10, 2024 at 5:26 PM Ard Biesheuvel <ardb+git@google.com> wrote:

> From: Ard Biesheuvel <ardb@kernel.org>
>
> The crc32/crc32c implementations using the scalar CRC32 instructions are
> accessed via indirect calls, and so they must be annotated with type ids
> in order to execute correctly when kCFI is enabled.
>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Fixes: 1a4fec49efe5 ("ARM: 9392/2: Support CLANG CFI")
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Thanks for helping to iron out the rough corners on these patches!

Yours,
Linus Walleij

Re: [PATCH] crypto: arm/crc32 - add kCFI annotations to asm routines

[Herbert Xu]

On Mon, Jun 10, 2024 at 05:26:39PM +0200, Ard Biesheuvel wrote:
> From: Ard Biesheuvel <ardb@kernel.org>
> 
> The crc32/crc32c implementations using the scalar CRC32 instructions are
> accessed via indirect calls, and so they must be annotated with type ids
> in order to execute correctly when kCFI is enabled.
> 
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
>  arch/arm/crypto/crc32-ce-core.S | 17 +++++++++--------
>  1 file changed, 9 insertions(+), 8 deletions(-)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt