1 files changed, 31 insertions, 14 deletions

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index c04d49e31f8..cff74b81a7d 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -391,14 +391,19 @@ static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
                 goto error;
         // else network stack removes extra byte if we forced a short packet
 
-        if (skb->len)
-                usbnet_skb_return (dev, skb);
-        else {
-                netif_dbg(dev, rx_err, dev->net, "drop\n");
-error:
-                dev->net->stats.rx_errors++;
-                skb_queue_tail (&dev->done, skb);
+        if (skb->len) {
+                /* all data was already cloned from skb inside the driver */
+                if (dev->driver_info->flags & FLAG_MULTI_PACKET)
+                        dev_kfree_skb_any(skb);
+                else
+                        usbnet_skb_return(dev, skb);
+                return;
         }
+
+        netif_dbg(dev, rx_err, dev->net, "drop\n");
+error:
+        dev->net->stats.rx_errors++;
+        skb_queue_tail(&dev->done, skb);
 }
 
 /*-------------------------------------------------------------------------*/
@@ -971,7 +976,8 @@ static void tx_complete (struct urb *urb)
         struct usbnet           *dev = entry->dev;
 
         if (urb->status == 0) {
-                dev->net->stats.tx_packets++;
+                if (!(dev->driver_info->flags & FLAG_MULTI_PACKET))
+                        dev->net->stats.tx_packets++;
                 dev->net->stats.tx_bytes += entry->length;
         } else {
                 dev->net->stats.tx_errors++;
@@ -1044,8 +1050,13 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
         if (info->tx_fixup) {
                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
                 if (!skb) {
-                        netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
-                        goto drop;
+                        if (netif_msg_tx_err(dev)) {
+                                netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
+                                goto drop;
+                        } else {
+                                /* cdc_ncm collected packet; waits for more */
+                                goto not_drop;
+                        }
                 }
         }
         length = skb->len;
@@ -1067,13 +1078,18 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
         /* don't assume the hardware handles USB_ZERO_PACKET
          * NOTE:  strictly conforming cdc-ether devices should expect
          * the ZLP here, but ignore the one-byte packet.
+         * NOTE2: CDC NCM specification is different from CDC ECM when
+         * handling ZLP/short packets, so cdc_ncm driver will make short
+         * packet itself if needed.
          */
         if (length % dev->maxpacket == 0) {
                 if (!(info->flags & FLAG_SEND_ZLP)) {
-                        urb->transfer_buffer_length++;
-                        if (skb_tailroom(skb)) {
-                                skb->data[skb->len] = 0;
-                                __skb_put(skb, 1);
+                        if (!(info->flags & FLAG_MULTI_PACKET)) {
+                                urb->transfer_buffer_length++;
+                                if (skb_tailroom(skb)) {
+                                        skb->data[skb->len] = 0;
+                                        __skb_put(skb, 1);
+                                }
                         }
                 } else
                         urb->transfer_flags |= URB_ZERO_PACKET;
@@ -1122,6 +1138,7 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
 drop:
                 dev->net->stats.tx_dropped++;
+not_drop:
                 if (skb)
                         dev_kfree_skb_any (skb);
                 usb_free_urb (urb);