[pim] IGMP "General Query" "Group-Specific Query" src and the Linux Kernel

<mal.hubert@bt.com> Thu, 14 March 2019 13:40 UTC

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From: mal.hubert@bt.com
To: pim@ietf.org
Thread-Topic: IGMP "General Query" "Group-Specific Query" src and the Linux Kernel
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Subject: [pim] IGMP "General Query" "Group-Specific Query" src and the Linux Kernel
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Hopefully someone on here can answer this basic query for me. It would appear that the Linux kernel by default will allow IGMPv3 "General Query" if it has a source IP of but will drop any "Group-Specific Queries" if the source IP is This doesn't appear to be specific to my implementation and seems to be the implementation in the Linux Kernel.

Some questions about this, if someone would be so kind as to help.

1)    Is this by design in the rfc3367 standard and would someone point out to me where it is and enlighten me as to why this is the case.

2)    Is this by design in the Kernel and would enlighten me as to why this is the case.

3)    Is this a bug in the Kernel and would it be worth raising on Kernel Bugzilla.

Many Thanks

Mal Hubert