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

[Andrei Botila]

From: Andrei Botila <andrei.bot...@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: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Signed-off-by: Andrei Botila <andrei.bot...@nxp.com>
---
 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