can: esd_usb2: don't touch skb after netif_rx()

There is no guarantee that the skb is in the same state after calling
net_receive_skb() or netif_rx(). It might be freed or reused. Not really
harmful as its a read access, except you turn on the proper debugging options
which catch a use after free.

Cc: Thomas Körper <thomas.koerper@esd.eu>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/usb/esd_usb2.c b/drivers/net/can/usb/esd_usb2.c
index 411c1af..0e5a449 100644 (file)
--- a/drivers/net/can/usb/esd_usb2.c
+++ b/drivers/net/can/usb/esd_usb2.c
@@ -301,13 +301,12 @@ static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
                        cf->data[7] = rxerr;
                }
 
-               netif_rx(skb);
-
                priv->bec.txerr = txerr;
                priv->bec.rxerr = rxerr;
 
                stats->rx_packets++;
                stats->rx_bytes += cf->can_dlc;
+               netif_rx(skb);
        }
 }
 
@@ -347,10 +346,9 @@ static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
                                cf->data[i] = msg->msg.rx.data[i];
                }
 
-               netif_rx(skb);
-
                stats->rx_packets++;
                stats->rx_bytes += cf->can_dlc;
+               netif_rx(skb);
        }
 
        return;