Commit 39707c2a authored by Hemant Kumar's avatar Hemant Kumar Committed by David S. Miller
Browse files

net: usb: Fix memory leak on Tx data path

Driver anchors the tx urbs and defers the urb submission if
a transmit request comes when the interface is suspended.
Anchoring urb increments the urb reference count. These
deferred urbs are later accessed by calling usb_get_from_anchor()
for submission during interface resume. usb_get_from_anchor()
unanchors the urb but urb reference count remains same.
This causes the urb reference count to remain non-zero
after usb_free_urb() gets called and urb never gets freed.
Hence call usb_put_urb() after anchoring the urb to properly
balance the reference count for these deferred urbs. Also,
unanchor these deferred urbs during disconnect, to free them
Signed-off-by: default avatarHemant Kumar <>
Acked-by: default avatarOliver Neukum <>
Signed-off-by: default avatarDavid S. Miller <>
parent bfc0d8c3
...@@ -1158,6 +1158,7 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb, ...@@ -1158,6 +1158,7 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
usb_anchor_urb(urb, &dev->deferred); usb_anchor_urb(urb, &dev->deferred);
/* no use to process more packets */ /* no use to process more packets */
netif_stop_queue(net); netif_stop_queue(net);
spin_unlock_irqrestore(&dev->txq.lock, flags); spin_unlock_irqrestore(&dev->txq.lock, flags);
netdev_dbg(dev->net, "Delaying transmission for resumption\n"); netdev_dbg(dev->net, "Delaying transmission for resumption\n");
goto deferred; goto deferred;
...@@ -1310,6 +1311,8 @@ void usbnet_disconnect (struct usb_interface *intf) ...@@ -1310,6 +1311,8 @@ void usbnet_disconnect (struct usb_interface *intf)
cancel_work_sync(&dev->kevent); cancel_work_sync(&dev->kevent);
if (dev->driver_info->unbind) if (dev->driver_info->unbind)
dev->driver_info->unbind (dev, intf); dev->driver_info->unbind (dev, intf);
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