net/hns3: fix RSS key with null

Since the patch '1848b117' has initialized the variable 'key' in
'struct rte_flow_action_rss' with 'NULL', the PMD will use the
default RSS key when create the first RSS rule with NULL RSS key.
Then, if create a repeated RSS rule with the above, it will not
identify duplicate rules and return an error message.

To solve the preceding problem, determine whether the current RSS keys
are the same based on whether the length of key_len of rss is 0.

Fixes: 1848b11 ("app/testpmd: fix RSS key for flow API RSS rule")
Cc: stable@dpdk.org

Signed-off-by: Lijun Ou <oulijun@huawei.com>

drivers/net/hns3/hns3_flow.c

@@ -1286,6 +1286,7 @@ static bool
 hns3_action_rss_same(const struct rte_flow_action_rss *comp,
 		     const struct rte_flow_action_rss *with)
 {
+	bool rss_key_is_same;
 	bool func_is_same;
 
 	/*
@@ -1302,11 +1303,16 @@ hns3_action_rss_same(const struct rte_flow_action_rss *comp,
 		func_is_same = (with->func != RTE_ETH_HASH_FUNCTION_DEFAULT) ?
 				(comp->func == with->func) : true;
 
-	return (func_is_same &&
+	if (with->key_len == 0 || with->key == NULL)
+		rss_key_is_same = 1;
+	else
+		rss_key_is_same = comp->key_len == with->key_len &&
+		!memcmp(comp->key, with->key, with->key_len);
+
+	return (func_is_same && rss_key_is_same &&
 		comp->types == (with->types & HNS3_ETH_RSS_SUPPORT) &&
-		comp->level == with->level && comp->key_len == with->key_len &&
+		comp->level == with->level &&
 		comp->queue_num == with->queue_num &&
-		!memcmp(comp->key, with->key, with->key_len) &&
 		!memcmp(comp->queue, with->queue,
 			sizeof(*with->queue) * with->queue_num));
 }