From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: skb_ip_make_writable and skbs not owned by a socket
Date: Tue, 18 Jan 2005 00:13:35 +0100
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Cc: rusty@rustcorp.com.au, netfilter-devel@lists.netfilter.org
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To: "David S. Miller" <davem@davemloft.net>
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David S. Miller wrote:

>This code is doing something different.  Even if we unclone and
>unshare the SKB, the packet header portion can still be non-linear.
>
>It will be possible for devices to create this situation on receive.
>That's why we have all the pskb_may_pull() checks in all the major
>ipv4 protocol input paths.
>
The patch already calls pskb_may_pull for unshared/uncloned skbs, so it
linearizes them up to the requested size. It just replaces skb_copy by
pskb_may_pull when the data area of unshared/uncloned skbs needs to be
mangled.

Regards
Patrick