crypto: caam - check zero-length input

Check zero-length input, for skcipher algorithm, to solve the extra
tests. This is a valid operation, therefore the API will return no error.
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Horia Geanta <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/caam/caamalg.c

@@ -1884,6 +1884,9 @@ static int skcipher_encrypt(struct skcipher_request *req)
 	u32 *desc;
 	int ret = 0;
 
+	if (!req->cryptlen)
+		return 0;
+
 	/* allocate extended descriptor */
 	edesc = skcipher_edesc_alloc(req, DESC_JOB_IO_LEN * CAAM_CMD_SZ);
 	if (IS_ERR(edesc))
@@ -1918,6 +1921,9 @@ static int skcipher_decrypt(struct skcipher_request *req)
 	u32 *desc;
 	int ret = 0;
 
+	if (!req->cryptlen)
+		return 0;
+
 	/* allocate extended descriptor */
 	edesc = skcipher_edesc_alloc(req, DESC_JOB_IO_LEN * CAAM_CMD_SZ);
 	if (IS_ERR(edesc))

drivers/crypto/caam/caamalg_qi.c

@@ -1445,6 +1445,9 @@ static inline int skcipher_crypt(struct skcipher_request *req, bool encrypt)
 	struct caam_ctx *ctx = crypto_skcipher_ctx(skcipher);
 	int ret;
 
+	if (!req->cryptlen)
+		return 0;
+
 	if (unlikely(caam_congested))
 		return -EAGAIN;
 

drivers/crypto/caam/caamalg_qi2.c

@@ -1499,6 +1499,9 @@ static int skcipher_encrypt(struct skcipher_request *req)
 	struct caam_request *caam_req = skcipher_request_ctx(req);
 	int ret;
 
+	if (!req->cryptlen)
+		return 0;
+
 	/* allocate extended descriptor */
 	edesc = skcipher_edesc_alloc(req);
 	if (IS_ERR(edesc))
@@ -1527,6 +1530,8 @@ static int skcipher_decrypt(struct skcipher_request *req)
 	struct caam_request *caam_req = skcipher_request_ctx(req);
 	int ret;
 
+	if (!req->cryptlen)
+		return 0;
 	/* allocate extended descriptor */
 	edesc = skcipher_edesc_alloc(req);
 	if (IS_ERR(edesc))