If the rx-offload skb_queue is full can_rx_offload_queue_sorted() will
not queue the skb and return with an error.
None of the callers of this function, issue a kfree_skb() to free the
not queued skb. This results in a memory leak.
This patch fixes the problem by freeing the skb in case of a full queue.
The return value is adjusted to -ENOBUFS to better reflect the actual
problem.
The device stats handling is left to the callers, as this function might
be used in both the rx and tx path.
Fixes: 55059f2b7f ("can: rx-offload: introduce can_rx_offload_get_echo_skb() and can_rx_offload_queue_sorted() functions")
Cc: linux-stable <stable@vger.kernel.org>
Cc: Martin Hundebøll <martin@geanix.com>
Reported-by: Martin Hundebøll <martin@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>