On Fri, Feb 06, 2026 at 03:52:12AM +0100, Linus Lüssing wrote: > If we are the only potential MLD querier but don't have an IPv6 > link-local address configured on our bridge interface then we can't > create a valid MLD query and in turn can't reliably receive MLD reports > and can't build a complete MDB. Hence disable the new multicast active > state variable then. Or reenable it if an IPv6 link-local address > became available. > > No functional change for the fast/data path yet. > > Signed-off-by: Linus Lüssing <[email protected]>
Reviewed-by: Ido Schimmel <[email protected]> > --- > net/bridge/br_multicast.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c > index 0fc29875db9c..a1cde2ba2a3e 100644 > --- a/net/bridge/br_multicast.c > +++ b/net/bridge/br_multicast.c > @@ -1125,6 +1125,7 @@ static void br_multicast_notify_active(struct > net_bridge_mcast *brmctx, > * The multicast active state is set, per protocol family, if: > * > * - an IGMP/MLD querier is present > + * - for own IPv6 MLD querier: an IPv6 address is configured on the bridge an IPv6 link-local address > * > * And is unset otherwise. > * > @@ -1222,10 +1223,12 @@ static struct sk_buff > *br_ip6_multicast_alloc_query(struct net_bridge_mcast *brm > &ip6h->daddr, 0, &ip6h->saddr)) { > kfree_skb(skb); > br_opt_toggle(brmctx->br, BROPT_HAS_IPV6_ADDR, false); > + br_multicast_update_active(brmctx); > return NULL; > } > > br_opt_toggle(brmctx->br, BROPT_HAS_IPV6_ADDR, true); > + br_multicast_update_active(brmctx); > ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest); > > hopopt = (u8 *)(ip6h + 1); > -- > 2.51.0 >
