crypto: mcryptd - pass through absence of ->setkey()

When the mcryptd template is used to wrap an unkeyed hash algorithm,
don't install a ->setkey() method to the mcryptd instance.  This change
is necessary for mcryptd to keep working with unkeyed hash algorithms
once we start enforcing that ->setkey() is called when present.

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

crypto/mcryptd.c

@@ -534,7 +534,8 @@ static int mcryptd_create_hash(struct crypto_template *tmpl, struct rtattr **tb,
 	inst->alg.finup  = mcryptd_hash_finup_enqueue;
 	inst->alg.export = mcryptd_hash_export;
 	inst->alg.import = mcryptd_hash_import;
-	inst->alg.setkey = mcryptd_hash_setkey;
+	if (crypto_hash_alg_has_setkey(halg))
+		inst->alg.setkey = mcryptd_hash_setkey;
 	inst->alg.digest = mcryptd_hash_digest_enqueue;
 
 	err = ahash_register_instance(tmpl, inst);