diff --git a/drivers/usb/serial/mos7720.c b/drivers/usb/serial/mos7720.c
index b418a0d4adb8..c713d98b4a20 100644
--- a/drivers/usb/serial/mos7720.c
+++ b/drivers/usb/serial/mos7720.c
@@ -226,8 +226,10 @@ static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
 	int status;
 
 	buf = kmalloc(1, GFP_KERNEL);
-	if (!buf)
+	if (!buf) {
+		*data = 0;
 		return -ENOMEM;
+	}
 
 	status = usb_control_msg(usbdev, pipe, request, requesttype, value,
 				     index, buf, 1, MOS_WDR_TIMEOUT);