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From: "Max Laier" <max@love2party.net>
To: "Haijin Yan" <yan@cs.uga.edu>, <freebsd-net@freebsd.org>
References: <Pine.GSO.4.44.0309031549530.2002-100000@atlas.cs.uga.edu>
Date: Wed, 3 Sep 2003 22:16:38 +0200
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cc: yan@cs.uga.edu
Subject: Re: ip_forward() crash
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So this page fault happens where? Maybe you want m_dup() rather than
m_copypacket() - esp. in case you get the page fault when trying to modify
the packet before sending it back to the sender.

Max

> Hi,
>   I am using freebsd 4.5 and in the ip_input.c at the place
> where IP decides to forward a mbuf not destined to itself,
> I added one of my function which included a call of ip_forward() to send
> out a my m_copyed mbuf to the sender. so basically there are two calls to
> ip_forward(), one is to relay mbuf from the sender and the other is
> forward back a copy of it. However, this behavior crashed my freebsd with
> trap 12 saying page fault in kernel. Does anyone have the same experience
> and know what's wrong with this?
>
>  Any suggestion is highly appreciated.
> please cc to me because I am not on the list.
>
> Thanks,
>
> -Haijin Yan