From 0078554d6a9df92ce25e07706c4e51143151b2c8 Mon Sep 17 00:00:00 2001
From: frosch <frosch@openttd.org>
Date: Sun, 10 Jan 2021 15:10:03 +0100
Subject: [PATCH] Fix: GetCargoTranslation could return out-of-bounds index for
 old-style NewGRF using cargo-slots.

---
 src/newgrf_cargo.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/newgrf_cargo.cpp b/src/newgrf_cargo.cpp
index 22c7120d82..c2859b71ef 100644
--- a/src/newgrf_cargo.cpp
+++ b/src/newgrf_cargo.cpp
@@ -91,7 +91,10 @@ uint16 GetCargoCallback(CallbackID callback, uint32 param1, uint32 param2, const
 CargoID GetCargoTranslation(uint8 cargo, const GRFFile *grffile, bool usebit)
 {
 	/* Pre-version 7 uses the 'climate dependent' ID in callbacks and properties, i.e. cargo is the cargo ID */
-	if (grffile->grf_version < 7 && !usebit) return cargo;
+	if (grffile->grf_version < 7 && !usebit) {
+		if (cargo >= CargoSpec::GetArraySize() || !CargoSpec::Get(cargo)->IsValid()) return CT_INVALID;
+		return cargo;
+	}
 
 	/* Other cases use (possibly translated) cargobits */