Return STATUS_INSUFFICIENT_BUFFER in SetupDiGetDeviceRegistryPropertyW if buffer for data was not specified.
This is not the same behaviour as RegQueryValueExW which returns a success in this case...

Modified: trunk/reactos/lib/setupapi/devinst.c

--- trunk/reactos/lib/setupapi/devinst.c	2005-10-25 15:29:42 UTC (rev 18771)
+++ trunk/reactos/lib/setupapi/devinst.c	2005-10-25 15:43:06 UTC (rev 18772)
@@ -2383,7 +2383,10 @@

                     *RequiredSize = BufferSize;
                 switch(rc) {
                     case ERROR_SUCCESS:

-                        ret = TRUE;

+                        if (PropertyBuffer != NULL || BufferSize == 0)
+                            ret = TRUE;
+                        else
+                            SetLastError(ERROR_INSUFFICIENT_BUFFER);

                         break;
                     case ERROR_MORE_DATA:
                         SetLastError(ERROR_INSUFFICIENT_BUFFER);