From 0050fa940c7d719a5f7f182e7b51bfdfb2a49fad Mon Sep 17 00:00:00 2001
From: Viktor Babrian <viktor.babrian@gmail.com>
Date: Tue, 14 Feb 2023 11:43:02 +0100
Subject: [PATCH] components/mdns: use semaphore instead of task notification
 bits (IDFGH-9380)

Component should not alter the task notification bits of the calling task.
---
 components/mdns/mdns.c                         | 15 ++++++++++++---
 components/mdns/private_include/mdns_private.h |  2 +-
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/components/mdns/mdns.c b/components/mdns/mdns.c
index 6a5c7b1097..b658b16ea1 100644
--- a/components/mdns/mdns.c
+++ b/components/mdns/mdns.c
@@ -4354,7 +4354,7 @@ static void _mdns_execute_action(mdns_action_t * action)
         _mdns_server->hostname = action->data.hostname_set.hostname;
         _mdns_self_host.hostname = action->data.hostname_set.hostname;
         _mdns_restart_all_pcbs();
-        xTaskNotifyGive(action->data.hostname_set.calling_task);
+        xSemaphoreGive(_mdns_server->action_sema);
         break;
     case ACTION_INSTANCE_SET:
         _mdns_send_bye_all_pcbs_no_instance(false);
@@ -4808,6 +4808,13 @@ esp_err_t mdns_init(void)
         err = ESP_ERR_NO_MEM;
         goto free_lock;
     }
+
+    _mdns_server->action_sema = xSemaphoreCreateBinary();
+    if (!_mdns_server->action_sema) {
+        err = ESP_ERR_NO_MEM;
+        goto free_queue;
+    }
+
     if ((err = esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &event_handler, NULL)) != ESP_OK) {
         goto free_event_handlers;
     }
@@ -4855,6 +4862,8 @@ free_event_handlers:
 #if CONFIG_ETH_ENABLED
     esp_event_handler_unregister(ETH_EVENT, ESP_EVENT_ANY_ID, &event_handler);
 #endif
+    vSemaphoreDelete(_mdns_server->action_sema);
+free_queue:
     vQueueDelete(_mdns_server->action_queue);
 free_lock:
     vSemaphoreDelete(_mdns_server->lock);
@@ -4908,6 +4917,7 @@ void mdns_free(void)
         }
         free(h);
     }
+    vSemaphoreDelete(_mdns_server->action_sema);
     vSemaphoreDelete(_mdns_server->lock);
     free(_mdns_server);
     _mdns_server = NULL;
@@ -4934,13 +4944,12 @@ esp_err_t mdns_hostname_set(const char * hostname)
     }
     action->type = ACTION_HOSTNAME_SET;
     action->data.hostname_set.hostname = new_hostname;
-    action->data.hostname_set.calling_task = xTaskGetCurrentTaskHandle();
     if (xQueueSend(_mdns_server->action_queue, &action, (portTickType)0) != pdPASS) {
         free(new_hostname);
         free(action);
         return ESP_ERR_NO_MEM;
     }
-    xTaskNotifyWait(0, 0, NULL, portMAX_DELAY);
+    xSemaphoreTake(_mdns_server->action_sema, portMAX_DELAY);
     return ESP_OK;
 }
 
diff --git a/components/mdns/private_include/mdns_private.h b/components/mdns/private_include/mdns_private.h
index 059d1ad252..bc937ff176 100644
--- a/components/mdns/private_include/mdns_private.h
+++ b/components/mdns/private_include/mdns_private.h
@@ -385,6 +385,7 @@ typedef struct mdns_server_s {
     mdns_srv_item_t * services;
     SemaphoreHandle_t lock;
     QueueHandle_t action_queue;
+    SemaphoreHandle_t action_sema;
     mdns_tx_packet_t * tx_queue_head;
     mdns_search_once_t * search_once;
     esp_timer_handle_t timer_handle;
@@ -395,7 +396,6 @@ typedef struct {
     union {
         struct {
             char * hostname;
-            xTaskHandle calling_task;
         } hostname_set;
         char * instance;
         struct {