Subject: Re: m_copyback patch.
To: Wolfgang Solfrank <ws@tools.de>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-kern
Date: 01/12/1998 10:16:45
On Mon, 12 Jan 1998 13:18:08 +0100 
 ws@tools.de (Wolfgang Solfrank) wrote:

 > The problem is that you cannot be sure that the mbuf does have MLEN/MHLEN
 > at the address pointer to by mh_data (and thus returned by the mtod macro).
 > The mh_data pointer might have been incremented beyond its initial value.
 > Hell, it even might have been setup with an offset to allow later insertion
 > of a header in front of the data placed into it initially.

Won't M_TRAILINGSPACE() give this to you?

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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