can: usb_8dev: usb_8dev_start_xmit(): fix double dev_kfree_skb() in error path

commit 3d3925ff64 upstream.

There is no need to call dev_kfree_skb() when usb_submit_urb() fails
because can_put_echo_skb() deletes original skb and
can_free_echo_skb() deletes the cloned skb.

Fixes: 0024d8ad16 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices")
Link: https://lore.kernel.org/all/20220311080614.45229-1-hbh25y@gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hangyu Hua 2022-03-11 16:06:14 +08:00 committed by Greg Kroah-Hartman
parent 869016a293
commit 5318cdf4fd

View file

@ -670,9 +670,20 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
atomic_inc(&priv->active_tx_urbs);
err = usb_submit_urb(urb, GFP_ATOMIC);
if (unlikely(err))
goto failed;
else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
if (unlikely(err)) {
can_free_echo_skb(netdev, context->echo_index);
usb_unanchor_urb(urb);
usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
atomic_dec(&priv->active_tx_urbs);
if (err == -ENODEV)
netif_device_detach(netdev);
else
netdev_warn(netdev, "failed tx_urb %d\n", err);
stats->tx_dropped++;
} else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
/* Slow down tx path */
netif_stop_queue(netdev);
@ -691,19 +702,6 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
return NETDEV_TX_BUSY;
failed:
can_free_echo_skb(netdev, context->echo_index);
usb_unanchor_urb(urb);
usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
atomic_dec(&priv->active_tx_urbs);
if (err == -ENODEV)
netif_device_detach(netdev);
else
netdev_warn(netdev, "failed tx_urb %d\n", err);
nomembuf:
usb_free_urb(urb);