Mbuf double-free guilty party detection patch

[Mike Silbersack]

On Sat, 25 Jun 2005, Peter Holm wrote:

> Maybe a panic is better: I got quite a few before I had to reset the
> box:
>
> 71 This memory last freed by: 0
> 18 This memory last freed by: 0x800
> 17 This memory last freed by: 0xdeadc0df
> 17 This memory last freed by: 0x1

Well, all of those are bad addresses due to the buggy first patch.  Try 
the new one I just sent out and see what you get.

If looking at caller addresses doesn't prove to be helpful, maybe we 
should print out the contents of each bad mbuf so that we can try 
to detect a pattern.

> I also added a backtrace and here's the high score:

Backtraces in the ctor or fini routine are meaningless, they just point to 
the next legitimate user of a mbuf, not the user who previously freed it 
(and then presumably used it after freeing it.)

Mike "Silby" Silbersack