ole32: Fail before constructing an object in CreateStreamOnHGlobal to avoid a memory leak.
diff --git a/dlls/ole32/hglobalstream.c b/dlls/ole32/hglobalstream.c
index e6d2f73..2175214 100644
--- a/dlls/ole32/hglobalstream.c
+++ b/dlls/ole32/hglobalstream.c
@@ -721,6 +721,9 @@
 {
   HGLOBALStreamImpl* newStream;
 
+  if (!ppstm)
+    return E_INVALIDARG;
+
   newStream = HGLOBALStreamImpl_Construct(hGlobal,
 					  fDeleteOnRelease);