From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] tcp: reduce skb overhead in selected places
Date: Wed, 25 Jan 2017 10:38:52 -0800
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         <20170125.131717.489451306351372553.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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On Wed, 2017-01-25 at 13:17 -0500, David Miller wrote:

> Applied, thanks Eric.

Thanks David.

It looks IPv6 potential big network headers are also a threat :

Various pskb_may_pull() to pull headers might reallocate skb->head,
but skb->truesize is not updated in __pskb_pull_tail()

We probably need to update skb->truesize, but it is tricky as the prior
skb->truesize value might have been used for memory accounting when skb
was stored in some queue.

Do you think we could change __pskb_pull_tail() right away and fix the
few places that would break, or should we add various helpers with extra
parameters to take a safe route ?