fix(lwip): Cleanup freertos port to use more readable checks

It also removes incorrect comment that's not valid any more (leftover from 6933c103e5)
It also removes ESP_THREAD_SAFE macro and sys_mbox_set_owner() which were not used
It also fixes CID 460613: Uninitialized pointer read in api_lib.c, netconn_gethostbyname_addrtype
Updated lwip submodule: git log --oneline 4297782b..aa4f6e78
* api_msg: Fix unused local variable if LWIP_NETCONN_SEM_PER_THREAD=1 (espressif/esp-lwip@aa4f6e78)

components/lwip/lwip

@@ -1 +1 @@
-Subproject commit 4297782bf9e614be1bb8605f30d46af8697fab17
+Subproject commit aa4f6e780f374af5e10730960fe0262a916166d1

components/lwip/port/freertos/include/arch/sys_arch.h

@@ -3,7 +3,7 @@
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
- * SPDX-FileContributor: 2018-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileContributor: 2018-2024 Espressif Systems (Shanghai) CO LTD
  */
 #ifndef __SYS_ARCH_H__
 #define __SYS_ARCH_H__
@@ -24,7 +24,6 @@ typedef TaskHandle_t sys_thread_t;
 
 typedef struct sys_mbox_s {
   QueueHandle_t os_mbox;
-  void *owner;
 }* sys_mbox_t;
 
 /** This is returned by _fromisr() sys functions to tell the outermost function
@@ -38,33 +37,17 @@ void sys_delay_ms(uint32_t ms);
 #define LWIP_COMPAT_MUTEX 0
 
 #if !LWIP_COMPAT_MUTEX
-#define sys_mutex_valid( x ) ( ( ( *x ) == NULL) ? pdFALSE : pdTRUE )
+#define sys_mutex_valid_val(mutex)   ((mutex) != NULL)
-#define sys_mutex_set_invalid( x ) ( ( *x ) = NULL )
+#define sys_mutex_valid(mutex)       (((mutex) != NULL) && sys_mutex_valid_val(*(mutex)))
+#define sys_mutex_set_invalid(mutex) ((*(mutex)) = NULL)
 #endif
 
-#define sys_mbox_valid( x ) ( ( ( *x ) == NULL) ? pdFALSE : pdTRUE )
+#define sys_mbox_valid(mbox)       (*(mbox) != NULL)
+#define sys_mbox_set_invalid(mbox) (*(mbox) = NULL)
 
-/* Define the sys_mbox_set_invalid() to empty to support lock-free mbox in ESP LWIP.
+#define sys_sem_valid_val(sema)   ((sema) != NULL)
- *
+#define sys_sem_valid(sema)       (((sema) != NULL) && sys_sem_valid_val(*(sema)))
- * The basic idea about the lock-free mbox is that the mbox should always be valid unless
+#define sys_sem_set_invalid(sema) ((*(sema)) = NULL)
- * no socket APIs are using the socket and the socket is closed. ESP LWIP achieves this by
- * following two changes to official LWIP:
- * 1. Postpone the deallocation of mbox to netconn_free(), in other words, free the mbox when
- *    no one is using the socket.
- * 2. Define the sys_mbox_set_invalid() to empty if the mbox is not actually freed.
-
- * The second change is necessary. Consider a common scenario: the application task calls
- * recv() to receive packets from the socket, the sys_mbox_valid() returns true. Because there
- * is no lock for the mbox, the LWIP CORE can call sys_mbox_set_invalid() to set the mbox at
- * anytime and the thread-safe issue may happen.
- *
- * However, if the sys_mbox_set_invalid() is not called after sys_mbox_free(), e.g. in netconn_alloc(),
- * we need to initialize the mbox to invalid explicitly since sys_mbox_set_invalid() now is empty.
- */
-#define sys_mbox_set_invalid( x )  *x = NULL
-
-#define sys_sem_valid( x ) ( ( (x) == NULL ) ? pdFALSE : ( ( *x ) == NULL ? pdFALSE : pdTRUE ) )
-#define sys_sem_set_invalid( x ) ( ( *x ) = NULL )
 
 void sys_delay_ms(uint32_t ms);
 sys_sem_t* sys_thread_sem_init(void);

components/lwip/port/freertos/sys_arch.c

@@ -3,7 +3,7 @@
  *
  * SPDX-License-Identifier: BSD-3-Clause
  *
- * SPDX-FileContributor: 2018-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileContributor: 2018-2024 Espressif Systems (Shanghai) CO LTD
  */
 
 /* lwIP includes. */
@@ -219,10 +219,6 @@ sys_mbox_new(sys_mbox_t *mbox, int size)
     return ERR_MEM;
   }
 
-#if ESP_THREAD_SAFE
-  (*mbox)->owner = NULL;
-#endif
-
   LWIP_DEBUGF(ESP_THREAD_SAFE_DEBUG, ("new *mbox ok mbox=%p os_mbox=%p\n", *mbox, (*mbox)->os_mbox));
   return ERR_OK;
 }
@@ -352,15 +348,6 @@ sys_arch_mbox_tryfetch(sys_mbox_t *mbox, void **msg)
   return 0;
 }
 
-void
-sys_mbox_set_owner(sys_mbox_t *mbox, void* owner)
-{
-  if (mbox && *mbox) {
-    (*mbox)->owner = owner;
-    LWIP_DEBUGF(ESP_THREAD_SAFE_DEBUG, ("set mbox=%p owner=%p", *mbox, owner));
-  }
-}
-
 /**
  * @brief Delete a mailbox
  *
@@ -444,7 +431,7 @@ sys_jiffies(void)
 }
 
 /**
- * @brief Get current time, in miliseconds
+ * @brief Get current time, in milliseconds
  *
  * @return current time
  */

components/lwip/port/include/lwipopts.h

@@ -1592,7 +1592,7 @@ static inline uint32_t timeout_from_offered(uint32_t lease, uint32_t min)
 #define ESP_LWIP                        1
 #define ESP_LWIP_ARP                    1
 #define ESP_PER_SOC_TCP_WND             0
-#define ESP_THREAD_SAFE                 1
+#define ESP_THREAD_SAFE                 1       /* Not used (to be removed in v6.x) */
 #define ESP_THREAD_SAFE_DEBUG           LWIP_DBG_OFF
 #define ESP_DHCP                        1
 #define ESP_DNS                         1
@@ -1630,12 +1630,10 @@ static inline uint32_t timeout_from_offered(uint32_t lease, uint32_t min)
 
 
 #if LWIP_NETCONN_SEM_PER_THREAD
-#if ESP_THREAD_SAFE
 #define LWIP_NETCONN_THREAD_SEM_GET() sys_thread_sem_get()
 #define LWIP_NETCONN_THREAD_SEM_ALLOC() sys_thread_sem_init()
 #define LWIP_NETCONN_THREAD_SEM_FREE() sys_thread_sem_deinit()
 #endif
-#endif
 
 /**
  * If CONFIG_ALLOC_MEMORY_IN_SPIRAM_FIRST is enabled, Try to