Merge branch 'bugfix/mdns_service_memory_leak_3.2' into 'release/v3.2'

mdns: fix memory leak when query for service plus various other fixes (Backport v3.2)

See merge request idf/esp-idf!4287

Author: projectgus

components/mdns/mdns.c

@@ -2741,8 +2741,10 @@ void mdns_parse_packet(mdns_rx_packet_t * packet)
 
                 if (search_result) {
                     if (search_result->type == MDNS_TYPE_PTR) {
-                        result->port = port;
-                        result->hostname = strdup(name->host);
+                        if (!result->hostname) { // assign host/port for this entry only if not previously set
+                            result->port = port;
+                            result->hostname = strdup(name->host);
+                        }
                     } else {
                         _mdns_search_result_add_srv(search_result, name->host, port, packet->tcpip_if, packet->ip_protocol);
                     }
@@ -2829,7 +2831,10 @@ void mdns_parse_packet(mdns_rx_packet_t * packet)
                             }
                         }
                     } else {
-                        _mdns_search_result_add_txt(search_result, txt, txt_count, packet->tcpip_if, packet->ip_protocol);
+                        _mdns_result_txt_create(data_ptr, data_len, &txt, &txt_count);
+                        if (txt_count) {
+                            _mdns_search_result_add_txt(search_result, txt, txt_count, packet->tcpip_if, packet->ip_protocol);
+                        }
                     }
                 } else if (ours) {
                     if (parsed_packet->questions && !parsed_packet->probe) {
@@ -4015,8 +4020,6 @@ static esp_err_t _mdns_service_task_stop()
     MDNS_SERVICE_LOCK();
     _mdns_stop_timer();
     MDNS_SERVICE_UNLOCK();
-    vSemaphoreDelete(_mdns_service_semaphore);
-    _mdns_service_semaphore = NULL;
     if (_mdns_service_task_handle) {
         mdns_action_t action;
         mdns_action_t * a = &action;
@@ -4029,6 +4032,8 @@ static esp_err_t _mdns_service_task_stop()
             vTaskDelay(10 / portTICK_PERIOD_MS);
         }
     }
+    vSemaphoreDelete(_mdns_service_semaphore);
+    _mdns_service_semaphore = NULL;
     return ESP_OK;
 }
 

components/mdns/mdns_networking.c

@@ -301,6 +301,7 @@ static err_t _mdns_udp_pcb_write_api(struct tcpip_api_call_data *api_call_msg)
     mdns_pcb_t * _pcb = &_mdns_server->interfaces[msg->tcpip_if].pcbs[msg->ip_protocol];
     esp_err_t err = tcpip_adapter_get_netif(msg->tcpip_if, &nif);
     if (err) {
+        pbuf_free(msg->pbt);
         msg->err = err;
         return err;
     }

examples/protocols/mdns/main/mdns_example_main.c

@@ -143,7 +143,7 @@ static void mdns_print_results(mdns_result_t * results){
         }
         a = r->addr;
         while(a){
-            if(a->addr.type == MDNS_IP_PROTOCOL_V6){
+            if(a->addr.type == IPADDR_TYPE_V6){
                 printf("  AAAA: " IPV6STR "\n", IPV62STR(a->addr.u_addr.ip6));
             } else {
                 printf("  A   : " IPSTR "\n", IP2STR(&(a->addr.u_addr.ip4)));