how to replace a skb in NF_IP_LOCAL_OUT hook

["jywang" <jywang@xxxxxxx>]

i want to replace the skb with my own, and in my skb i will change the data
in it. 

How to do it?

what i do as below:

 cp = skb_copy_expand(*skb, skb_headroom(*skb)+12, skb_tailroom(*skb), GFP_ATOMIC);
//change the skb->data here
 skb_set_owner_w(cp, (*skb)->sk);
 *skb = cp;
 return NF_ACCEPT;

but, it can't work.




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 姓名：      王金一   
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 Name:       jinyi wang
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