can: cc770: 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: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/cc770/cc770.c b/drivers/net/can/cc770/cc770.c
index c11d4498403617e4dddcea42d085e08355c9a5d2..70a8cbb29e75844a02bea49a937bf0c05a200910 100644 (file)
--- a/drivers/net/can/cc770/cc770.c
+++ b/drivers/net/can/cc770/cc770.c
@@ -504,10 +504,10 @@ static void cc770_rx(struct net_device *dev, unsigned int mo, u8 ctrl1)
                for (i = 0; i < cf->can_dlc; i++)
                        cf->data[i] = cc770_read_reg(priv, msgobj[mo].data[i]);
        }
-       netif_rx(skb);
 
        stats->rx_packets++;
        stats->rx_bytes += cf->can_dlc;
+       netif_rx(skb);
 }
 
 static int cc770_err(struct net_device *dev, u8 status)
@@ -584,10 +584,10 @@ static int cc770_err(struct net_device *dev, u8 status)
                }
        }
 
-       netif_rx(skb);
 
        stats->rx_packets++;
        stats->rx_bytes += cf->can_dlc;
+       netif_rx(skb);
 
        return 0;
 }