tree c0470809aa6a3e92fce6c0b37757ab58e75e9dc5
parent 9672723973f1e70189b8409eb2da189a980481c5
author Eric Dumazet <edumazet@google.com> 1423831632 -0800
committer David S. Miller <davem@davemloft.net> 1423840300 -0800

tcp: make sure skb is not shared before using skb_get()

IPv6 can keep a copy of SYN message using skb_get() in
tcp_v6_conn_request() so that caller wont free the skb when calling
kfree_skb() later.

Therefore TCP fast open has to clone the skb it is queuing in
child->sk_receive_queue, as all skbs consumed from receive_queue are
freed using __kfree_skb() (ie assuming skb->users == 1)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Fixes: 5b7ed0892f2af ("tcp: move fastopen functions to tcp_fastopen.c")
Signed-off-by: David S. Miller <davem@davemloft.net>