Subject: Re: PR15662, why was it backed out?
To: Tad Hunt <tad@entrisphere.com>
From: Sean Boudreau <seanb@qnx.com>
List: tech-kern
Date: 01/06/2003 08:55:05
FWIW, 1.72 was only around for about half an hour.  1.73
should have the fix without the bug.

-seanb

On Fri, Jan 03, 2003 at 03:52:53PM -0800, Tad Hunt wrote:
> 
> I'm running into the same problem described in PR15662, though I
> can reproduce the behavior with a simpler setup.  I believe that
> the code Christos committed to fix this problem should be fixed,
> not backed out.

<snip>

> 
> According to the commit message from itojun when the code was backed
> out:
> 
> 	> CVS log for src/sys/netinet/in.c  Revision 1.76
> 	>
> 	> backout 1.72.  it is not correct for the kernel to remove routes
> 	> by itself, and the code was buggy (dereferenced null pointer when
> 	> IFAFREE removes the route).
> 
> Other than backing it out because it was buggy, I am not clear on
> why the kernel is not *required* to remove routes which no longer
> make any sense.
> 
> When an interface address is removed or changed, I don't think that
> any more packets should exit the box stamped with that source
> address.  This problem is clearly in the domain of the kernel to
> rectify.  Those routes no longer make sense, and userland apparently
> has no knowledge of which source address the kernel is going to
> stamp into the outgoing packet.
> 
> -Tad