[ldv-project] [PATCH] can: ems_usb: fix urb leaks on failure paths

[Sebastian Haas]

Looks good. Thanks Alexey.

Acked-by: Sebastian Haas <dev at sebastianhaas.info>

On 07 Dec 2013, at 12:42, Oliver Hartkopp <socketcan at hartkopp.net> wrote:

> Hello Alexey,
> 
> looks better :-)
> 
> I added the author of this driver to double check the patch and for his
> Acked-by ...
> 
> @Sebastian: Would you like to update your e-mail address too?
> 
> Best regards,
> Oliver
> 
> 
> On 07.12.2013 00:10, Alexey Khoroshilov wrote:
>> 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 at ispras.ru>
>> ---
>> drivers/net/can/usb/ems_usb.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/net/can/usb/ems_usb.c b/drivers/net/can/usb/ems_usb.c
>> index 5f9a7ad9b964..8aeec0b4601a 100644
>> --- 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");
>> 
>>