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Date: Wed, 5 Jul 2017 13:05:12 +0200
From: Marius Strobl <marius@freebsd.org>
To: Vincenzo Maffione <v.maffione@gmail.com>
Cc: FreeBSD Net <freebsd-net@freebsd.org>
Subject: Re: NULL pointer dereference bug triggered by netmap
Message-ID: <20170705110512.GA28058@alchemy.franken.de>
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On Mon, Jul 03, 2017 at 05:08:09PM +0200, Vincenzo Maffione wrote:
> Details here:
> 
> https://github.com/luigirizzo/netmap/issues/322
> 
> Is it acceptable to commit the proposed patch?

As suggested by hselasky@, the outliner problem at hand is better solved
by a dummy if_start method in order to not hurt the fast-path. Thus, if
anything at all, a KASSERT(ifp->if_start != NULL, "no if_start method")
should be added to if_handoff() and if_start().

Marius