Re: [PATCH] net/ipv4/arp.c: Fix arp reply when sender ip 0

David Miller
2007-11-16T09:06:14Z

From: "Jonas Danielsson" <the.sator@gmail.com>
Date: Fri, 16 Nov 2007 09:30:11 +0100

> 2007/11/16, David Miller <davem@davemloft.net>:
> > From: "Jonas Danielsson" <the.sator@gmail.com>
> > Date: Thu, 15 Nov 2007 22:40:13 +0100
> >
> > > Is there a reason that the target hardware address isn't the target
> > > hardware address?
> >
>
>
> > Because of this, in cases where a choice can be made Linux will
> > advertise what is most likely to result in successful communication.
> >
> > This is likely why we are changing that target address to the one of
> > the interface actually sending back the reply rather than the zero
> > value you used.
> >
> > In fact I think this information can be useful to the sender of
> > the DAD request.
> >
>
> There seem to be some confusion about what my patch really does. It
> does not set the hardware address to a zero value.

I knew you were talking about the IP address not the hardware
address.

> The reply from the Linux kernel in computer A, before the patch would look like:
>
> Reply:
> Opcode: reply (0x0002)
> Sender HW: 00:AA.00:AA:00:AA
> Sender IP: 192.168.0.1
> Target HW: 00:AA:00:AA:00:AA
> Target IP: 192.168.0.1

And this is exactly a sensible response in my opinion.