From f55aadfedf73ba3a653c2cd440bb4d101bfe6e3c Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Mon, 11 Jul 2022 09:17:18 +1000
Subject: [PATCH] HAL_SITL: fixed undefined behaviour in GPIO

---
 libraries/AP_HAL_SITL/GPIO.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/libraries/AP_HAL_SITL/GPIO.cpp b/libraries/AP_HAL_SITL/GPIO.cpp
index 27c9b06c0a..9ad575b908 100644
--- a/libraries/AP_HAL_SITL/GPIO.cpp
+++ b/libraries/AP_HAL_SITL/GPIO.cpp
@@ -29,6 +29,9 @@ uint8_t GPIO::read(uint8_t pin)
     if (!_sitlState->_sitl) {
         return 0;
     }
+    if (!valid_pin(pin)) {
+        return 0;
+    }
     
     // weight on wheels pin support
     if (pin == _sitlState->_sitl->wow_pin.get()) {
@@ -45,6 +48,9 @@ void GPIO::write(uint8_t pin, uint8_t value)
         return;
     }
 
+    if (!valid_pin(pin)) {
+        return;
+    }
     if (pin < 8) {
         if (!(pin_mode_is_write & (1U<<pin))) {
             // ignore setting of pull-up resistors