skb_copy -- copy an sk_buff
struct sk_buff * skb_copy
(const struct sk_buff * skb, int gfp_mask);
buffer to copy
Make a copy of both an &sk_buff and its data. This is used when the
caller wishes to modify the data and needs a private copy of the
data to alter. Returns NULL on failure or the pointer to the buffer
on success. The returned buffer has a reference count of 1.
You must pass GFP_ATOMIC as the allocation priority if this function
is called from an interrupt.