can: Unify droping of invalid tx skbs and netdev stats
To prevent the CAN drivers to operate on invalid socketbuffers the skbs are
now checked and silently dropped at the xmit-function consistently.
Also the netdev stats are consistently using the CAN data length code (dlc)
for [rx|tx]_bytes now.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 3db7767..7e7c98a 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -60,6 +60,21 @@
*/
#define get_can_dlc(i) (min_t(__u8, (i), 8))
+/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
+static inline int can_dropped_invalid_skb(struct net_device *dev,
+ struct sk_buff *skb)
+{
+ const struct can_frame *cf = (struct can_frame *)skb->data;
+
+ if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) {
+ kfree_skb(skb);
+ dev->stats.tx_dropped++;
+ return 1;
+ }
+
+ return 0;
+}
+
struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
void free_candev(struct net_device *dev);