can: ems_usb: fix urb leaks on failure paths

There are a couple failure paths where urb leaks.
Is spare code within ems_usb_start_xmit(),
usb_free_urb() should be used to deallocate urb instead of usb_unanchor_urb().
In ems_usb_start() there is no usb_free_urb() if usb_submit_urb() fails.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Sebastian Haas <dev@sebastianhaas.info>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/usb/ems_usb.c b/drivers/net/can/usb/ems_usb.c
index 5f9a7ad..8aeec0b 100644 (file)
--- a/drivers/net/can/usb/ems_usb.c
+++ b/drivers/net/can/usb/ems_usb.c
@@ -625,6 +625,7 @@ static int ems_usb_start(struct ems_usb *dev)
                        usb_unanchor_urb(urb);
                        usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
                                          urb->transfer_dma);
+                       usb_free_urb(urb);
                        break;
                }
 
@@ -798,8 +799,8 @@ static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *ne
         * allowed (MAX_TX_URBS).
         */
        if (!context) {
-               usb_unanchor_urb(urb);
                usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
+               usb_free_urb(urb);
 
                netdev_warn(netdev, "couldn't find free context\n");