From bfc905ff75ce3a35c0f874937a6def8d117f1c8b Mon Sep 17 00:00:00 2001
From: Nico de Poel <ndepoel@gmail.com>
Date: Sun, 16 Mar 2025 19:09:54 +0100
Subject: [PATCH] Added some extra safety checks

---
 FSR3UnityPlugin.cpp | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/FSR3UnityPlugin.cpp b/FSR3UnityPlugin.cpp
index c2baf1c..df16636 100644
--- a/FSR3UnityPlugin.cpp
+++ b/FSR3UnityPlugin.cpp
@@ -173,16 +173,15 @@ static uint32_t AllocateFeatureSlot()
 
 static void FreeFeatureSlot(uint32_t featureSlot)
 {
+    // Prevent duplicate free slots
+    auto& slots = s_FeatureSlots._Get_container();
+    if (std::find(slots.begin(), slots.end(), featureSlot) != slots.end())
+        return;
+
     s_FeatureSlots.push(featureSlot);
     memset(&s_Features[featureSlot], 0, sizeof(FSR3Feature));
 }
 
-static PFN_vkVoidFunction GetVulkanDeviceProcAddr(VkDevice device, const char* pName)
-{
-    UnityVulkanInstance instance = s_GraphicsVulkan->Instance();
-    return instance.getInstanceProcAddr(instance.instance, pName);
-}
-
 static bool LoadFidelityFXLibrary(_In_ LPCWSTR lpLibFileName)
 {
     s_ffxModule = LoadLibrary(lpLibFileName);
@@ -229,6 +228,12 @@ static bool LoadFidelityFXLibrary(_In_ LPCWSTR lpLibFileName)
     return true;
 }
 
+static PFN_vkVoidFunction GetVulkanDeviceProcAddr(VkDevice device, const char* pName)
+{
+    UnityVulkanInstance instance = s_GraphicsVulkan->Instance();
+    return instance.getInstanceProcAddr(instance.instance, pName);
+}
+
 extern "C" bool UNITY_INTERFACE_EXPORT UNITY_INTERFACE_API AMDUP_InitApi()
 {
     std::lock_guard<std::mutex> lock(s_FeatureMutex);
@@ -276,6 +281,8 @@ extern "C" bool UNITY_INTERFACE_EXPORT UNITY_INTERFACE_API AMDUP_InitApi()
 static void DestroyFeature(uint32_t featureSlot)
 {
     auto& feature = s_Features[featureSlot];
+    if (feature.upscalingContext == nullptr && !feature.isValid)
+        return;
 
     if (s_GraphicsD3D12 != nullptr)
     {