From 58ed22461fc5dc9b93dedf154d3c839c026eb73a Mon Sep 17 00:00:00 2001
From: David Cermak <cermak@espressif.com>
Date: Mon, 4 Mar 2019 12:32:10 +0100
Subject: [PATCH] mdns: enable pcbs before starting service thread to avoid
 updating pcb's internal variables from concurent tasks

possible race condition: user task runs mdns_init, which enables pcbs while mdns-task already created could execute enable/disable of the same pcbs if an appropriate system event received
---
 components/mdns/mdns.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/components/mdns/mdns.c b/components/mdns/mdns.c
index 268f7c280..b8c7edb99 100644
--- a/components/mdns/mdns.c
+++ b/components/mdns/mdns.c
@@ -4084,12 +4084,6 @@ esp_err_t mdns_init()
         goto free_lock;
     }
 
-    if (_mdns_service_task_start()) {
-        //service start failed!
-        err = ESP_FAIL;
-        goto free_all;
-    }
-
     uint8_t i;
     ip6_addr_t tmp_addr6;
     tcpip_adapter_ip_info_t if_ip_info;
@@ -4103,9 +4097,19 @@ esp_err_t mdns_init()
         }
     }
 
+    if (_mdns_service_task_start()) {
+        //service start failed!
+        err = ESP_FAIL;
+        goto free_all_and_disable_pcbs;
+    }
+
     return ESP_OK;
 
-free_all:
+free_all_and_disable_pcbs:
+    for (i=0; i<TCPIP_ADAPTER_IF_MAX; i++) {
+        _mdns_disable_pcb(i, MDNS_IP_PROTOCOL_V6);
+        _mdns_disable_pcb(i, MDNS_IP_PROTOCOL_V4);
+    }
     vQueueDelete(_mdns_server->action_queue);
 free_lock:
     vSemaphoreDelete(_mdns_server->lock);