From ee750edd0a104f379e48dc64dbbf742c9a3b334b Mon Sep 17 00:00:00 2001
From: blueshogun96 <blueshogun96@aim.com>
Date: Tue, 2 May 2017 14:50:50 -0700
Subject: [PATCH] Error checking for D3DVertexBuffer_Lock

---
 src/CxbxKrnl/EmuD3D8.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/CxbxKrnl/EmuD3D8.cpp b/src/CxbxKrnl/EmuD3D8.cpp
index 6c99283ef..316f0a267 100644
--- a/src/CxbxKrnl/EmuD3D8.cpp
+++ b/src/CxbxKrnl/EmuD3D8.cpp
@@ -7591,6 +7591,13 @@ VOID WINAPI XTL::EMUPATCH(D3DVertexBuffer_Lock)
 
     IDirect3DVertexBuffer8 *pVertexBuffer8 = pVertexBuffer->EmuVertexBuffer8;
 
+	// Let's verify this VB exists before trying to lock it...
+	if( !pVertexBuffer8 )
+	{
+		EmuWarning("EmuVertexBuffer8 == NULL!");
+		return;
+	}
+
     HRESULT hRet = pVertexBuffer8->Lock(OffsetToLock, SizeToLock, ppbData, Flags);
     if(FAILED(hRet))
         EmuWarning("VertexBuffer Lock Failed!");