diff --git a/reactos/drivers/usb/usbuhci/usb_request.cpp b/reactos/drivers/usb/usbuhci/usb_request.cpp
index 685d09c7dbe..0b4a074c7fd 100644
--- a/reactos/drivers/usb/usbuhci/usb_request.cpp
+++ b/reactos/drivers/usb/usbuhci/usb_request.cpp
@@ -1020,6 +1020,9 @@ CUSBRequest::BuildBulkInterruptTransferDescriptor(
     {
         // get buffer base
         m_Base = MmGetMdlVirtualAddress(m_TransferBufferMDL);
+
+        // sanity check
+        ASSERT(m_Base != NULL);
     }
 
     // get new buffer offset