[PATCH 05/22] crypto: powerpc/aes-spe - add check for xts input length equal to zero

[Andrei Botila]

From: Andrei Botila <andrei.botila@xxxxxxx>

Standardize the way input lengths equal to 0 are handled in all skcipher
algorithms. All the algorithms return 0 for input lengths equal to zero.

Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Andrei Botila <andrei.botila@xxxxxxx>
---
 arch/powerpc/crypto/aes-spe-glue.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/crypto/aes-spe-glue.c b/arch/powerpc/crypto/aes-spe-glue.c
index c2b23b69d7b1..f37d8bef322b 100644
--- a/arch/powerpc/crypto/aes-spe-glue.c
+++ b/arch/powerpc/crypto/aes-spe-glue.c
@@ -327,6 +327,9 @@ static int ppc_xts_encrypt(struct skcipher_request *req)
 	u8 b[2][AES_BLOCK_SIZE];
 	int err;
 
+	if (!req->cryptlen)
+		return 0;
+
 	if (req->cryptlen < AES_BLOCK_SIZE)
 		return -EINVAL;
 
@@ -366,6 +369,9 @@ static int ppc_xts_decrypt(struct skcipher_request *req)
 	le128 twk;
 	int err;
 
+	if (!req->cryptlen)
+		return 0;
+
 	if (req->cryptlen < AES_BLOCK_SIZE)
 		return -EINVAL;
 
-- 
2.17.1