From 4c9b6d24c683e917bc40fabd4c52e24e4cf394e3 Mon Sep 17 00:00:00 2001
From: "Earle F. Philhower, III" <earlephilhower@yahoo.com>
Date: Sat, 27 Jul 2024 11:35:52 -0700
Subject: [PATCH] LwIpIntfDev.end() check _started to prevent crash

From @JAndrassy https://github.com/esp8266/Arduino/pull/9173
---
 libraries/lwIP_Ethernet/src/LwipIntfDev.h | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/libraries/lwIP_Ethernet/src/LwipIntfDev.h b/libraries/lwIP_Ethernet/src/LwipIntfDev.h
index d90a15710..a6756f43c 100644
--- a/libraries/lwIP_Ethernet/src/LwipIntfDev.h
+++ b/libraries/lwIP_Ethernet/src/LwipIntfDev.h
@@ -427,18 +427,20 @@ bool LwipIntfDev<RawDev>::begin(const uint8_t* macAddress, const uint16_t mtu) {
 
 template<class RawDev>
 void LwipIntfDev<RawDev>::end() {
-    if (_intrPin < 0) {
-        __removeEthernetPacketHandler(_phID);
-    } else {
-        detachInterrupt(_intrPin);
-        __removeEthernetGPIO(_intrPin);
-    }
+    if (_started) {
+        if (_intrPin < 0) {
+            __removeEthernetPacketHandler(_phID);
+        } else {
+            detachInterrupt(_intrPin);
+            __removeEthernetGPIO(_intrPin);
+        }
 
-    RawDev::end();
+        RawDev::end();
 
-    netif_remove(&_netif);
+        netif_remove(&_netif);
 
-    _started = false;
+        _started = false;
+    }
 }
 
 template<class RawDev>