On the gated mailing list, there is currently a thread discussing
possibilities where BSD based kernels will have serious problems if you have
more than 2^16 routes associated with any one interface.  This is something
that has the real possibility of happening with modern BGP routers.

I read that the FreeBSD solution was to change "short ifa_refcnt" in if.h to a
long.

Looking at the "netbsd-current" source at ftp.netbsd.org, it looks like we
have ifa_refcnt as a short.  I guess its possible that this is a problem with
NetBSD.  I couldn't find anything related to it in the gnats database.

I'm forwarding this information to the list in case anybody was interested in
this potential problem.  Maybe Somebody Who Knows What They Are Doing might
want to look at it.

Erik 

---------- Forwarded message ----------
Date: Wed, 14 Jul 1999 20:51:34 -0400
From: Mike Tancsa <mike@sentex.net>
To: Andrew Bangs <andrewb@demon.net>
Cc: gated-people@merit.edu
Subject: Re: 64K problems?

>> Quoting from the PR,
>> -------------
>> The total number of routes isn't the problem, but if the number of
>> routes on a single interface goes above 2^16 and later falls below
>> 2^16 then the reference counter hits zero and we free (IFAFREE in
>> if.h and ifafree() in route.c) the ifa.  Subsequent route deletions
>> cause a panic was we flail around looking for a reference counter
>> to decrement in a structure that we've just freed (at least, that's
>> the behaviour in OpenBSD, and the code elsewhere looks the same).
>> -------------
>
>... which is why we found and fixed this bug. It wasn't fun.
>
>(and I still don't know how I missed the typo right in the middle of
>the bit you quoted. Probably a coffee deficiency that day.)

Hi,

Did you fix it on 2.2.x as well ? Or just on 3.x ?

	---Mike
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