We are calling usbnet_start_xmit() to flush any remaining data,
depending on the side effect that tx_curr_skb is set to NULL,
ensuring a new allocation using the updated tx_max. But this
side effect will only happen if there were any cached data ready
to transmit. If not, then an empty tx_curr_skb is still allocated
using the old tx_max size. Free it to avoid a buffer overrun.
Fixes: 68864abf08 ("net: cdc_ncm: support rx_max/tx_max updates when running")
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
1ba5d0ff36