[PATCH 8/8] crypto: null - use memcpy_sglist()

[Eric Biggers <ebiggers@kernel.org>]

From: Eric Biggers <ebiggers@google.com>

Make null_skcipher_crypt() use memcpy_sglist() instead of the
skcipher_walk API, as this is simpler.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 crypto/crypto_null.c | 17 ++++-------------
 1 file changed, 4 insertions(+), 13 deletions(-)

diff --git a/crypto/crypto_null.c b/crypto/crypto_null.c
index 48c71b925f37..34588f39fdfc 100644
--- a/crypto/crypto_null.c
+++ b/crypto/crypto_null.c
@@ -13,10 +13,11 @@
  */
 
 #include <crypto/null.h>
 #include <crypto/internal/hash.h>
 #include <crypto/internal/skcipher.h>
+#include <crypto/scatterwalk.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/string.h>
 
 static int null_init(struct shash_desc *desc)
@@ -58,23 +59,13 @@ static void null_crypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 	memcpy(dst, src, NULL_BLOCK_SIZE);
 }
 
 static int null_skcipher_crypt(struct skcipher_request *req)
 {
-	struct skcipher_walk walk;
-	int err;
-
-	err = skcipher_walk_virt(&walk, req, false);
-
-	while (walk.nbytes) {
-		if (walk.src.virt.addr != walk.dst.virt.addr)
-			memcpy(walk.dst.virt.addr, walk.src.virt.addr,
-			       walk.nbytes);
-		err = skcipher_walk_done(&walk, 0);
-	}
-
-	return err;
+	if (req->src != req->dst)
+		memcpy_sglist(req->dst, req->src, req->cryptlen);
+	return 0;
 }
 
 static struct shash_alg digest_null = {
 	.digestsize		=	NULL_DIGEST_SIZE,
 	.setkey   		=	null_hash_setkey,
-- 
2.49.0