Subject: Re: [PATCH net-next-2.6] can: Unify droping of invalid tx skbs and netdev stats

From: Marc Kleine-Budde <[email-masked]>
Date: Mon, 11 Jan 2010 20:11:15 +0100

Oliver Hartkopp wrote:
> Wolfgang Grandegger wrote:
> 
>>>  
>>> +	if (skb->len != sizeof(*cf) || cf->can_dlc > 8) {
>>> +		kfree_skb(skb);
>>> +		dev->stats.tx_dropped++;
>>> +		return NETDEV_TX_OK;
>>> +	}
>> A static inline function "invalid_can_skb(skb)" (or "no_can_skb") would
>> be handy here:
>>
>> 	if (invalid_can_skb(skb)) {
>> 		kfree_skb(skb);
>> 		dev->stats.tx_dropped++;
>> 		return NETDEV_TX_OK;		
>> 	}
> 
> Another idea could be:
> 
> 	if (can_dropped_invalid_skb(skb, dev))
> 		return NETDEV_TX_OK;
> 
> with
> 
> static inline int can_dropped_invalid_skb(struct sk_buff *skb, struct net_device *dev)
> {
> 	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;
> }

this functions looks nice, but I'd swap its arguments, in order to have
the same signature as the alloc_can_skb() functions

cheers, Marc

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