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.