From 486f13440fc98e294b42012010ebe87671803d47 Mon Sep 17 00:00:00 2001
From: duncanspumpkin <duncans_pumpkin@hotmail.co.uk>
Date: Sat, 17 Aug 2019 11:02:14 +0100
Subject: [PATCH] Fix #9875. Check for valid tile element before dereferencing

---
 src/openrct2/ride/TrackDesign.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/openrct2/ride/TrackDesign.cpp b/src/openrct2/ride/TrackDesign.cpp
index 2a690c1365..94acdb97f7 100644
--- a/src/openrct2/ride/TrackDesign.cpp
+++ b/src/openrct2/ride/TrackDesign.cpp
@@ -1648,6 +1648,11 @@ static bool track_design_place_ride(TrackDesign* td6, int16_t x, int16_t y, int1
                     TileElement* tile_element = map_get_first_element_at(tile.x >> 5, tile.y >> 5);
                     z = gTrackPreviewOrigin.z / 8;
                     z += (entrance.z == (int8_t)(uint8_t)0x80) ? -1 : entrance.z;
+                    if (tile_element == nullptr)
+                    {
+                        _trackDesignPlaceCost = MONEY32_UNDEFINED;
+                        return false;
+                    }
 
                     do
                     {