diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index 96a70789b4c215376914aaa1196785bff53ce312..4d6a5c672a3d1fd388c6f318c3000e1cfef354cb 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -496,12 +496,10 @@ static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
 	void *dmabuf;
 	int result;
 
-	dmabuf = kmalloc(bufsize, GFP_KERNEL);
+	dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
 	if (!dmabuf)
 		return -ENOMEM;
 
-	memcpy(dmabuf, buf, bufsize);
-
 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 			req, REQTYPE_HOST_TO_INTERFACE, 0,
 			port_priv->bInterfaceNumber, dmabuf, bufsize,