Re: [PATCH 4.9 27/75] net: igmp: Use correct source address on IGMPv3 reports

From: Kevin Cernekee
Date: Mon Jan 15 2018 - 23:32:44 EST


On Mon, Jan 15, 2018 at 8:26 PM, Sebastian Gottschall
<s.gottschall@xxxxxxxxxx> wrote:
> havent check the source addresses right now. i basicly discovered that this
> patch breaks the igmp routing and all traffic stops
> this here is from a working system with the reverted patch. if you really
> need that i break it again using the patch you need to wait a little bit
>
> 05:14:22.697962 IP 10.88.195.138 > 239.35.100.8: igmp v2 report 239.35.100.8

The patch should only affect IGMPv3 behavior. I did not intend to
change IGMPv2 behavior. If it does, that might be a bug.

Is it possible that the kernel is using a source IP of 0.0.0.0, but
another host does not recognize it because it does not comply with RFC
3376?

Before/after packet traces would be the best way to see if the kernel
change is causing it to violate the standard.