diff --git a/lib/luks2/luks2_json_metadata.c b/lib/luks2/luks2_json_metadata.c
index b681ce21..52782f2f 100644
--- a/lib/luks2/luks2_json_metadata.c
+++ b/lib/luks2/luks2_json_metadata.c
@@ -447,15 +447,15 @@ static int hdr_validate_json_size(json_object *hdr_jobj)
 {
 	json_object *jobj, *jobj1;
 	const char *json;
-	size_t json_area_size, json_size;
+	uint64_t json_area_size, json_size;
 
 	json_object_object_get_ex(hdr_jobj, "config", &jobj);
 	json_object_object_get_ex(jobj, "json_size", &jobj1);
 
 	json = json_object_to_json_string_ext(hdr_jobj,
 		JSON_C_TO_STRING_PLAIN | JSON_C_TO_STRING_NOSLASHESCAPE);
-	json_area_size = (size_t)json_object_get_uint64(jobj1);
-	json_size = strlen(json);
+	json_area_size = json_object_get_uint64(jobj1);
+	json_size = (uint64_t)strlen(json);
 
 	return json_size > json_area_size ? 1 : 0;
 }
diff --git a/lib/luks2/luks2_keyslot.c b/lib/luks2/luks2_keyslot.c
index f31980e5..1519ccaa 100644
--- a/lib/luks2/luks2_keyslot.c
+++ b/lib/luks2/luks2_keyslot.c
@@ -594,7 +594,7 @@ int LUKS2_keyslots_validate(json_object *hdr_jobj)
 		json_object_object_get_ex(val, "type", &jobj_type);
 		h = LUKS2_keyslot_handler_type(NULL, json_object_get_string(jobj_type));
 		if (!h)
-			return 0;
+			continue;
 		if (h->validate && h->validate(NULL, val)) {
 			log_dbg("Keyslot type %s validation failed on keyslot %d.", h->name, keyslot);
 			return -EINVAL;