From mboxrd@z Thu Jan  1 00:00:00 1970
From: RongQing Li <roy.qing.li@gmail.com>
Subject: Re: [PATCH net-next 1/2] ipv6: remove unnecessary codes in tcp_ipv6.c
Date: Mon, 2 Jul 2012 13:23:09 +0800
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	<20120701.202610.12425223200611171.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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2012/7/2 David Miller <davem@davemloft.net>:
> From: roy.qing.li@gmail.com
> Date: Mon,  2 Jul 2012 11:18:59 +0800
>
>> -     if (opt) {
>> -             newnp->opt = ipv6_dup_options(newsk, opt);
>> -             if (opt != np->opt)
>> -                     sock_kfree_s(sk, opt, opt->tot_len);
>
> This is bogus, if we copy the options into a new copy in
> ipv6_dup_options() we have to free the old one or else we
> leak it.

Do you mean I should free newnp->opt firstly ?

If I understand it right, I think we do not need to free it. the
process is below:

newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst);
..
newnp = inet6_sk(newsk);
..
memcpy(newnp, np, sizeof(struct ipv6_pinfo));
..
newnp->opt         = NULL;

So newnp->opt is not a effective memory.


Thanks.
-Roy