[PATCH v2 2/2] crypto: x86/aesni - Update aesni_set_key() to return void

[Chang S. Bae]

The aesni_set_key() implementation has no error case, yet its prototype
specifies to return an error code.

Modify the function prototype to return void and adjust the related code.

Signed-off-by: Chang S. Bae <chang.seok.bae@xxxxxxxxx>
Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: x86@xxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
V2 <- V1:
* Ensure not to return an uninitialized value. (Ard Biesheuvel)

Previously, Eric identified a similar case in my AES-KL code [1]. Then,
this parallel issue was realized.
[1]: https://lore.kernel.org/lkml/20230607053558.GC941@sol.localdomain/
---
 arch/x86/crypto/aesni-intel_asm.S  | 5 ++---
 arch/x86/crypto/aesni-intel_glue.c | 8 ++++----
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S
index 411d8c83e88a..7ecb55cae3d6 100644
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -1820,8 +1820,8 @@ SYM_FUNC_START_LOCAL(_key_expansion_256b)
 SYM_FUNC_END(_key_expansion_256b)
 
 /*
- * int aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
- *                   unsigned int key_len)
+ * void aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
+ *                    unsigned int key_len)
  */
 SYM_FUNC_START(aesni_set_key)
 	FRAME_BEGIN
@@ -1926,7 +1926,6 @@ SYM_FUNC_START(aesni_set_key)
 	sub $0x10, UKEYP
 	cmp TKEYP, KEYP
 	jb .Ldec_key_loop
-	xor AREG, AREG
 #ifndef __x86_64__
 	popl KEYP
 #endif
diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 8b3b17b065ad..0ea3abaaa645 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -87,8 +87,8 @@ static inline void *aes_align_addr(void *addr)
 	return PTR_ALIGN(addr, AESNI_ALIGN);
 }
 
-asmlinkage int aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
-			     unsigned int key_len);
+asmlinkage void aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
+			      unsigned int key_len);
 asmlinkage void aesni_enc(const void *ctx, u8 *out, const u8 *in);
 asmlinkage void aesni_dec(const void *ctx, u8 *out, const u8 *in);
 asmlinkage void aesni_ecb_enc(struct crypto_aes_ctx *ctx, u8 *out,
@@ -241,9 +241,9 @@ static int aes_set_key_common(struct crypto_aes_ctx *ctx,
 		return err;
 
 	kernel_fpu_begin();
-	err = aesni_set_key(ctx, in_key, key_len);
+	aesni_set_key(ctx, in_key, key_len);
 	kernel_fpu_end();
-	return err;
+	return 0;
 }
 
 static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
-- 
2.34.1