ACK: [PATCH 1/1][Xenial] crypto: arm64/sha - avoid non-standard inline asm tricks

Kleber Souza kleber.souza at canonical.com
Thu Jan 21 17:06:30 UTC 2021


On 16.01.21 00:32, dann frazier wrote:
> From: Ard Biesheuvel <ard.biesheuvel at linaro.org>
> 
> BugLink: https://bugs.launchpad.net/bugs/1907489
> 
> commit f4857f4c2ee9aa4e2aacac1a845352b00197fb57 upstream.
> 
> Replace the inline asm which exports struct offsets as ELF symbols
> with proper const variables exposing the same values. This works
> around an issue with Clang which does not interpret the "i" (or "I")
> constraints in the same way as GCC.
> 
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
> Tested-by: Matthias Kaehlcke <mka at chromium.org>
> Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
> Signed-off-by: Nathan Chancellor <natechancellor at gmail.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Signed-off-by: Juerg Haefliger <juergh at canonical.com>
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>
> Signed-off-by: dann frazier <dann.frazier at canonical.com>

Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>

> ---
>   arch/arm64/crypto/sha1-ce-core.S |  6 ++++--
>   arch/arm64/crypto/sha1-ce-glue.c | 11 +++--------
>   arch/arm64/crypto/sha2-ce-core.S |  6 ++++--
>   arch/arm64/crypto/sha2-ce-glue.c | 13 +++++--------
>   4 files changed, 16 insertions(+), 20 deletions(-)
> 
> diff --git a/arch/arm64/crypto/sha1-ce-core.S b/arch/arm64/crypto/sha1-ce-core.S
> index c98e7e849f06..8550408735a0 100644
> --- a/arch/arm64/crypto/sha1-ce-core.S
> +++ b/arch/arm64/crypto/sha1-ce-core.S
> @@ -82,7 +82,8 @@ ENTRY(sha1_ce_transform)
>   	ldr		dgb, [x0, #16]
>   
>   	/* load sha1_ce_state::finalize */
> -	ldr		w4, [x0, #:lo12:sha1_ce_offsetof_finalize]
> +	ldr_l		w4, sha1_ce_offsetof_finalize, x4
> +	ldr		w4, [x0, x4]
>   
>   	/* load input */
>   0:	ld1		{v8.4s-v11.4s}, [x1], #64
> @@ -132,7 +133,8 @@ CPU_LE(	rev32		v11.16b, v11.16b	)
>   	 * the padding is handled by the C code in that case.
>   	 */
>   	cbz		x4, 3f
> -	ldr		x4, [x0, #:lo12:sha1_ce_offsetof_count]
> +	ldr_l		w4, sha1_ce_offsetof_count, x4
> +	ldr		x4, [x0, x4]
>   	movi		v9.2d, #0
>   	mov		x8, #0x80000000
>   	movi		v10.2d, #0
> diff --git a/arch/arm64/crypto/sha1-ce-glue.c b/arch/arm64/crypto/sha1-ce-glue.c
> index 01e48b8970b1..1b7b4684c35b 100644
> --- a/arch/arm64/crypto/sha1-ce-glue.c
> +++ b/arch/arm64/crypto/sha1-ce-glue.c
> @@ -17,9 +17,6 @@
>   #include <linux/crypto.h>
>   #include <linux/module.h>
>   
> -#define ASM_EXPORT(sym, val) \
> -	asm(".globl " #sym "; .set " #sym ", %0" :: "I"(val));
> -
>   MODULE_DESCRIPTION("SHA1 secure hash using ARMv8 Crypto Extensions");
>   MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel at linaro.org>");
>   MODULE_LICENSE("GPL v2");
> @@ -32,6 +29,9 @@ struct sha1_ce_state {
>   asmlinkage void sha1_ce_transform(struct sha1_ce_state *sst, u8 const *src,
>   				  int blocks);
>   
> +const u32 sha1_ce_offsetof_count = offsetof(struct sha1_ce_state, sst.count);
> +const u32 sha1_ce_offsetof_finalize = offsetof(struct sha1_ce_state, finalize);
> +
>   static int sha1_ce_update(struct shash_desc *desc, const u8 *data,
>   			  unsigned int len)
>   {
> @@ -52,11 +52,6 @@ static int sha1_ce_finup(struct shash_desc *desc, const u8 *data,
>   	struct sha1_ce_state *sctx = shash_desc_ctx(desc);
>   	bool finalize = !sctx->sst.count && !(len % SHA1_BLOCK_SIZE) && len;
>   
> -	ASM_EXPORT(sha1_ce_offsetof_count,
> -		   offsetof(struct sha1_ce_state, sst.count));
> -	ASM_EXPORT(sha1_ce_offsetof_finalize,
> -		   offsetof(struct sha1_ce_state, finalize));
> -
>   	/*
>   	 * Allow the asm code to perform the finalization if there is no
>   	 * partial data and the input is a round multiple of the block size.
> diff --git a/arch/arm64/crypto/sha2-ce-core.S b/arch/arm64/crypto/sha2-ce-core.S
> index 01cfee066837..679c6c002f4f 100644
> --- a/arch/arm64/crypto/sha2-ce-core.S
> +++ b/arch/arm64/crypto/sha2-ce-core.S
> @@ -88,7 +88,8 @@ ENTRY(sha2_ce_transform)
>   	ld1		{dgav.4s, dgbv.4s}, [x0]
>   
>   	/* load sha256_ce_state::finalize */
> -	ldr		w4, [x0, #:lo12:sha256_ce_offsetof_finalize]
> +	ldr_l		w4, sha256_ce_offsetof_finalize, x4
> +	ldr		w4, [x0, x4]
>   
>   	/* load input */
>   0:	ld1		{v16.4s-v19.4s}, [x1], #64
> @@ -136,7 +137,8 @@ CPU_LE(	rev32		v19.16b, v19.16b	)
>   	 * the padding is handled by the C code in that case.
>   	 */
>   	cbz		x4, 3f
> -	ldr		x4, [x0, #:lo12:sha256_ce_offsetof_count]
> +	ldr_l		w4, sha256_ce_offsetof_count, x4
> +	ldr		x4, [x0, x4]
>   	movi		v17.2d, #0
>   	mov		x8, #0x80000000
>   	movi		v18.2d, #0
> diff --git a/arch/arm64/crypto/sha2-ce-glue.c b/arch/arm64/crypto/sha2-ce-glue.c
> index 7a7f95b94869..356ca9397a86 100644
> --- a/arch/arm64/crypto/sha2-ce-glue.c
> +++ b/arch/arm64/crypto/sha2-ce-glue.c
> @@ -17,9 +17,6 @@
>   #include <linux/crypto.h>
>   #include <linux/module.h>
>   
> -#define ASM_EXPORT(sym, val) \
> -	asm(".globl " #sym "; .set " #sym ", %0" :: "I"(val));
> -
>   MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
>   MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel at linaro.org>");
>   MODULE_LICENSE("GPL v2");
> @@ -32,6 +29,11 @@ struct sha256_ce_state {
>   asmlinkage void sha2_ce_transform(struct sha256_ce_state *sst, u8 const *src,
>   				  int blocks);
>   
> +const u32 sha256_ce_offsetof_count = offsetof(struct sha256_ce_state,
> +					      sst.count);
> +const u32 sha256_ce_offsetof_finalize = offsetof(struct sha256_ce_state,
> +						 finalize);
> +
>   static int sha256_ce_update(struct shash_desc *desc, const u8 *data,
>   			    unsigned int len)
>   {
> @@ -52,11 +54,6 @@ static int sha256_ce_finup(struct shash_desc *desc, const u8 *data,
>   	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
>   	bool finalize = !sctx->sst.count && !(len % SHA256_BLOCK_SIZE) && len;
>   
> -	ASM_EXPORT(sha256_ce_offsetof_count,
> -		   offsetof(struct sha256_ce_state, sst.count));
> -	ASM_EXPORT(sha256_ce_offsetof_finalize,
> -		   offsetof(struct sha256_ce_state, finalize));
> -
>   	/*
>   	 * Allow the asm code to perform the finalization if there is no
>   	 * partial data and the input is a round multiple of the block size.
> 




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