Some skcipher algo has no IV buffer such as ecb(aes) also, here add
checking with ivsize.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
---
 .../virtio/virtio_crypto_skcipher_algs.c      | 39 +++++++++++--------
 1 file changed, 23 insertions(+), 16 deletions(-)

diff --git a/drivers/crypto/virtio/virtio_crypto_skcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_skcipher_algs.c
index 3d47e7c30c6b..a5e6993da2ef 100644
--- a/drivers/crypto/virtio/virtio_crypto_skcipher_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_skcipher_algs.c
@@ -345,7 +345,9 @@ __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
 			src_nents, dst_nents);
 
 	/* Why 3?  outhdr + iv + inhdr */
-	sg_total = src_nents + dst_nents + 3;
+	sg_total = src_nents + dst_nents + 2;
+	if (ivsize)
+		sg_total += 1;
 	sgs = kcalloc_node(sg_total, sizeof(*sgs), GFP_KERNEL,
 				dev_to_node(&vcrypto->vdev->dev));
 	if (!sgs)
@@ -402,15 +404,17 @@ __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
 	 * Avoid to do DMA from the stack, switch to using
 	 * dynamically-allocated for the IV
 	 */
-	iv = vc_sym_req->iv;
-	memcpy(iv, req->iv, ivsize);
-	if (!vc_sym_req->encrypt)
-		scatterwalk_map_and_copy(req->iv, req->src,
-					 req->cryptlen - ivsize,
-					 ivsize, 0);
-
-	sg_init_one(&iv_sg, iv, ivsize);
-	sgs[num_out++] = &iv_sg;
+	if (ivsize) {
+		iv = vc_sym_req->iv;
+		memcpy(iv, req->iv, ivsize);
+		if (!vc_sym_req->encrypt)
+			scatterwalk_map_and_copy(req->iv, req->src,
+					req->cryptlen - ivsize,
+					ivsize, 0);
+
+		sg_init_one(&iv_sg, iv, ivsize);
+		sgs[num_out++] = &iv_sg;
+	}
 
 	/* Source data */
 	for (sg = req->src; src_nents; sg = sg_next(sg), src_nents--)
@@ -437,7 +441,8 @@ __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
 	return 0;
 
 free_iv:
-	memzero_explicit(iv, ivsize);
+	if (ivsize)
+		memzero_explicit(iv, ivsize);
 free:
 	memzero_explicit(req_data, sizeof(*req_data));
 	kfree(sgs);
@@ -543,11 +548,13 @@ static void virtio_crypto_skcipher_finalize_req(
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	unsigned int ivsize = crypto_skcipher_ivsize(tfm);
 
-	if (vc_sym_req->encrypt)
-		scatterwalk_map_and_copy(req->iv, req->dst,
-					 req->cryptlen - ivsize,
-					 ivsize, 0);
-	memzero_explicit(vc_sym_req->iv, ivsize);
+	if (ivsize) {
+		if (vc_sym_req->encrypt)
+			scatterwalk_map_and_copy(req->iv, req->dst,
+					req->cryptlen - ivsize,
+					ivsize, 0);
+		memzero_explicit(vc_sym_req->iv, ivsize);
+	}
 	virtcrypto_clear_request(&vc_sym_req->base);
 
 	crypto_finalize_skcipher_request(vc_sym_req->base.dataq->engine,
-- 
2.39.3