Re: [PATCH net-next 0/3] rtnetlink: dump link-layer multicast addresses

Le 05/09/2026 à 11:39, Yuyang Huang a écrit :

"ip maddr show" prints three kinds of entries: link-layer, IPv4 and
IPv6. The IPv4 and IPv6 ones can be read over netlink today: IPv6 has
had RTM_GETMULTICAST for a long time and IPv4 got it in eb4e17a1d915
("netlink: support dumping IPv4 multicast addresses"), with IFA_MC_USERS
added later so the user count no longer has to come from procfs.

quoted

The link-layer list is the missing piece. dev->mc, the addresses

programmed into the device filter, is only exported via
/proc/net/dev_mcast, so iproute2 still carries a procfs parser just for

These addresses could be listed with 'bridge fdb' (RTM_GETNEIGH on AF_BRIDGE).
Instead of having a new message to get the missing info (users), maybe it would
be better to update the current API.

that. This series closes the gap so that "ip maddr show" can be served
from rtnetlink alone.

Patch 1 handles RTM_GETMULTICAST dumps with ifa_family set to AF_PACKET

FWIW, AF_PACKET seems strange to me. Isn't AF_UNSPEC (like for interface, cf
rtnl_fill_ifinfo) more appropriate?

Regards,
Nicolas