crypto: skcipher - pass instance to crypto_grab_skcipher()

Initializing a crypto_skcipher_spawn currently requires:

1. Set spawn->base.inst to point to the instance.
2. Call crypto_grab_skcipher().

But there's no reason for these steps to be separate, and in fact this
unneeded complication has caused at least one bug, the one fixed by
commit 6db4341017 ("crypto: adiantum - initialize crypto_spawn::inst")

So just make crypto_grab_skcipher() take the instance as an argument.

To keep the function calls from getting too unwieldy due to this extra
argument, also introduce a 'mask' variable into the affected places
which weren't already using one.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/cts.c

@@ -328,6 +328,7 @@ static int crypto_cts_create(struct crypto_template *tmpl, struct rtattr **tb)
 	struct crypto_attr_type *algt;
 	struct skcipher_alg *alg;
 	const char *cipher_name;
+	u32 mask;
 	int err;
 
 	algt = crypto_get_attr_type(tb);
@@ -337,6 +338,8 @@ static int crypto_cts_create(struct crypto_template *tmpl, struct rtattr **tb)
 	if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask)
 		return -EINVAL;
 
+	mask = crypto_requires_sync(algt->type, algt->mask);
+
 	cipher_name = crypto_attr_alg_name(tb[1]);
 	if (IS_ERR(cipher_name))
 		return PTR_ERR(cipher_name);
@@ -347,10 +350,8 @@ static int crypto_cts_create(struct crypto_template *tmpl, struct rtattr **tb)
 
 	spawn = skcipher_instance_ctx(inst);
 
-	crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst));
-	err = crypto_grab_skcipher(spawn, cipher_name, 0,
-				   crypto_requires_sync(algt->type,
-							algt->mask));
+	err = crypto_grab_skcipher(spawn, skcipher_crypto_instance(inst),
+				   cipher_name, 0, mask);
 	if (err)
 		goto err_free_inst;