4 files changed, 9 insertions, 6 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 38bfdb0..3f10459 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -550,7 +550,7 @@ static void acm_waker(struct work_struct *waker)
 static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 {
 	struct acm *acm;
-	int rv = -EINVAL;
+	int rv = -ENODEV;
 	int i;
 	dbg("Entering acm_tty_open.");
 
@@ -677,7 +677,7 @@ static void acm_tty_close(struct tty_struct *tty, struct file *filp)
 
 	/* Perform the closing process and see if we need to do the hardware
 	   shutdown */
-	if (tty_port_close_start(&acm->port, tty, filp) == 0)
+	if (!acm || tty_port_close_start(&acm->port, tty, filp) == 0)
 		return;
 	acm_port_down(acm, 0);
 	tty_port_close_end(&acm->port, tty);
diff --git a/drivers/usb/gadget/f_phonet.c b/drivers/usb/gadget/f_phonet.c
index 96fb118..d17f108 100644
--- a/drivers/usb/gadget/f_phonet.c
+++ b/drivers/usb/gadget/f_phonet.c
@@ -256,7 +256,7 @@ out:
 		dev_kfree_skb(skb);
 		dev->stats.tx_dropped++;
 	}
-	return 0;
+	return NETDEV_TX_OK;
 }
 
 static int pn_net_mtu(struct net_device *dev, int new_mtu)
diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c
index 016f63b..aac69b5 100644
--- a/drivers/usb/gadget/u_ether.c
+++ b/drivers/usb/gadget/u_ether.c
@@ -487,7 +487,7 @@ static int eth_start_xmit(struct sk_buff *skb, struct net_device *net)
 
 	if (!in) {
 		dev_kfree_skb_any(skb);
-		return 0;
+		return NETDEV_TX_OK;
 	}
 
 	/* apply outgoing CDC or RNDIS filters */
@@ -506,7 +506,7 @@ static int eth_start_xmit(struct sk_buff *skb, struct net_device *net)
 				type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
 			if (!(cdc_filter & type)) {
 				dev_kfree_skb_any(skb);
-				return 0;
+				return NETDEV_TX_OK;
 			}
 		}
 		/* ignores USB_CDC_PACKET_TYPE_DIRECTED */
@@ -586,7 +586,7 @@ drop:
 		list_add(&req->list, &dev->tx_reqs);
 		spin_unlock_irqrestore(&dev->req_lock, flags);
 	}
-	return 0;
+	return NETDEV_TX_OK;
 }
 
 /*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index d595aa5..a842164 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -333,6 +333,9 @@ static void serial_close(struct tty_struct *tty, struct file *filp)
 {
 	struct usb_serial_port *port = tty->driver_data;
 
+	if (!port)
+		return;
+
 	dbg("%s - port %d", __func__, port->number);