From d906034d9505750345c5bd122f01154cb1266521 Mon Sep 17 00:00:00 2001
From: Shubham Patil <shubham.patil@espressif.com>
Date: Fri, 25 Aug 2023 18:23:00 +0530
Subject: [PATCH] [ESP32] Enable LWIP_TCPIP_CORE_LOCKING by default and added
 static assert for the same (#28798)

* [ESP32] Enable LWIP_TCPIP_CORE_LOCKING by default and acquire lwip locks
when initializing route_hook

* inet: static assert if LWIP_TCPIP_CORE_LOCKING is disabled

Static assert is disabled for ASR and bouffalolab platforms

* typo
---
 config/esp32/components/chip/Kconfig          | 11 ++++++++
 src/inet/UDPEndPointImplLwIP.cpp              |  5 ++++
 .../ESP32/route_hook/ESP32RouteHook.c         | 25 +++++++++++++++++--
 3 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/config/esp32/components/chip/Kconfig b/config/esp32/components/chip/Kconfig
index ee259a3244b4ca..aef77a9941826c 100644
--- a/config/esp32/components/chip/Kconfig
+++ b/config/esp32/components/chip/Kconfig
@@ -174,6 +174,17 @@ menu "CHIP Core"
             help
                 Enable this option to start a UDP Endpoint queue filter for mDNS Broadcast packets
 
+        config ENABLE_LWIP_THREAD_SAFETY
+            bool "Enable LwIP Thread safety options"
+            default y
+            select LWIP_TCPIP_CORE_LOCKING
+            select LWIP_CHECK_THREAD_SAFETY
+            help
+                CHIP SDK performs LwIP core locking before calling an LwIP API.
+                To make the calls thread safe we have to enable LWIP_TCPIP_CORE_LOCKING.
+                Here, we are also enabling LWIP_CHECK_THREAD_SAFETY which will assert when
+                LwIP code gets called from any other context or without holding the LwIP lock.
+
     endmenu # "Networking Options"
 
     menu "System Options"
diff --git a/src/inet/UDPEndPointImplLwIP.cpp b/src/inet/UDPEndPointImplLwIP.cpp
index d3e87e1dd0ca42..8690fb3839377c 100644
--- a/src/inet/UDPEndPointImplLwIP.cpp
+++ b/src/inet/UDPEndPointImplLwIP.cpp
@@ -41,6 +41,11 @@
 
 static_assert(LWIP_VERSION_MAJOR > 1, "CHIP requires LwIP 2.0 or later");
 
+#if !(CHIP_DEVICE_LAYER_TARGET_BL602 || CHIP_DEVICE_LAYER_TARGET_BL702 || CHIP_DEVICE_LAYER_TARGET_BL702L ||                       \
+      CHIP_DEVICE_LAYER_TARGET_ASR)
+static_assert(LWIP_TCPIP_CORE_LOCKING, "CHIP requires config LWIP_TCPIP_CORE_LOCKING enabled");
+#endif
+
 #if !defined(RAW_FLAGS_MULTICAST_LOOP) || !defined(UDP_FLAGS_MULTICAST_LOOP) || !defined(raw_clear_flags) ||                       \
     !defined(raw_set_flags) || !defined(udp_clear_flags) || !defined(udp_set_flags)
 #define HAVE_LWIP_MULTICAST_LOOP 0
diff --git a/src/platform/ESP32/route_hook/ESP32RouteHook.c b/src/platform/ESP32/route_hook/ESP32RouteHook.c
index df19adf1de13e8..f19cf59ebf90b2 100644
--- a/src/platform/ESP32/route_hook/ESP32RouteHook.c
+++ b/src/platform/ESP32/route_hook/ESP32RouteHook.c
@@ -17,10 +17,12 @@
 #include "lwip/icmp6.h"
 #include "lwip/mld6.h"
 #include "lwip/netif.h"
+#include "lwip/opt.h"
 #include "lwip/prot/icmp6.h"
 #include "lwip/prot/ip6.h"
 #include "lwip/prot/nd6.h"
 #include "lwip/raw.h"
+#include "lwip/tcpip.h"
 
 #define HOPLIM_MAX 255
 #define PIO_FLAG_ON_LINK (1 << 7)
@@ -155,25 +157,41 @@ esp_err_t esp_route_hook_init(esp_netif_t * netif)
     esp_err_t ret           = ESP_OK;
 
     ESP_RETURN_ON_FALSE(netif != NULL, ESP_ERR_INVALID_ARG, TAG, "Invalid network interface");
+
+    LOCK_TCPIP_CORE();
+
     int netif_idx = esp_netif_get_netif_impl_index(netif);
     if (netif_idx < 0 || netif_idx > UINT8_MAX)
     {
+        UNLOCK_TCPIP_CORE();
         return ESP_ERR_INVALID_SIZE;
     }
     lwip_netif = netif_get_by_index((uint8_t) netif_idx);
-    ESP_RETURN_ON_FALSE(lwip_netif != NULL, ESP_ERR_INVALID_ARG, TAG, "Invalid network interface");
+
+    if (lwip_netif == NULL)
+    {
+        UNLOCK_TCPIP_CORE();
+        ESP_LOGE(TAG, "Invalid network interface");
+        return ESP_ERR_INVALID_ARG;
+    }
 
     for (esp_route_hook_t * iter = s_hooks; iter != NULL; iter = iter->next)
     {
         if (iter->netif == lwip_netif)
         {
+            UNLOCK_TCPIP_CORE();
             ESP_LOGI(TAG, "Hook already installed on netif, skip...");
             return ESP_OK;
         }
     }
 
     hook = (esp_route_hook_t *) malloc(sizeof(esp_route_hook_t));
-    ESP_RETURN_ON_FALSE(hook != NULL, ESP_ERR_NO_MEM, TAG, "Cannot allocate hook");
+    if (hook == NULL)
+    {
+        UNLOCK_TCPIP_CORE();
+        ESP_LOGE(TAG, "Cannot allocate hook");
+        return ESP_ERR_NO_MEM;
+    }
 
     ESP_GOTO_ON_FALSE(mld6_joingroup_netif(lwip_netif, ip_2_ip6(&router_group)) == ESP_OK, ESP_FAIL, exit, TAG,
                       "Failed to join multicast group");
@@ -189,6 +207,9 @@ esp_err_t esp_route_hook_init(esp_netif_t * netif)
     s_hooks    = hook;
 
 exit:
+
+    UNLOCK_TCPIP_CORE();
+
     if (ret != ESP_OK && hook != NULL)
     {
         free(hook);