[PATCH 10/22] crypto: atmel-aes - add check for xts input length equal to zero

[Andrei Botila]

From: Andrei Botila <andrei.botila at nxp.com>

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: Nicolas Ferre <nicolas.ferre at microchip.com>
Cc: Alexandre Belloni <alexandre.belloni at bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches at microchip.com>
Signed-off-by: Andrei Botila <andrei.botila at nxp.com>
---
 drivers/crypto/atmel-aes.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/crypto/atmel-aes.c b/drivers/crypto/atmel-aes.c
index a6e14491e080..af789ac73478 100644
--- a/drivers/crypto/atmel-aes.c
+++ b/drivers/crypto/atmel-aes.c
@@ -1107,6 +1107,10 @@ static int atmel_aes_crypt(struct skcipher_request *req, unsigned long mode)
 		ctx->block_size = CFB64_BLOCK_SIZE;
 		break;
 
+	case AES_FLAGS_XTS:
+		if (!req->cryptlen)
+			return 0;
+
 	default:
 		ctx->block_size = AES_BLOCK_SIZE;
 		break;
-- 
2.17.1