From mboxrd@z Thu Jan  1 00:00:00 1970
From: Weilong Chen <chenweilong@huawei.com>
Subject: Re: [PATCH net-next] net: Check frag_lists first to prevent data out
 of order
Date: Fri, 28 Aug 2015 13:34:13 +0800
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> From: Weilong Chen <chenweilong@huawei.com>
> Date: Fri, 28 Aug 2015 11:35:40 +0800
>
>> In my test, @to has a fraglist, but skb_tailroom(to) is not 0!
>> The test is about tipc, the function tipc_buf_append will merge 3 skbs
>> to one:
>> packet 1: len = 1420 skb_tailroom = 190
>> packet 2: len = 1420
>> 	packet 2 will be add to 1' fraglist, but not update skb_tailroom
>
> This operation is illegal.
>
> Once there are frags, tailroom is not permitted.
>
> .
>

Agree

Thanks