[PATCH iproute2-next] bridge: mcast: add mcast_active_v4 / mcast_active_v6 output

[PATCH iproute2-next] bridge: mcast: add mcast_active_v4 / mcast_active_v6 output

[Linus Lüssing]

Add output for the mcast_active_v4 and mcast_active_v6 states. If their
output is 1 then IGMP/MLD snooping is applied to multicast payload
traffic of their according protocol family. This is the case when:

* the bridge interface is up
* multicast snooping is enabled
* an IGMP/MLD querier is present
* for own IPv6 MLD querier: an IPv6 address is configured on the bridge

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
 bridge/vlan.c                  | 10 ++++++++++
 include/uapi/linux/if_bridge.h |  2 ++
 include/uapi/linux/if_link.h   |  2 ++
 ip/iplink_bridge.c             | 12 ++++++++++++
 4 files changed, 26 insertions(+)

diff --git a/bridge/vlan.c b/bridge/vlan.c
index 3c240207028b..d0b6afdee49d 100644
--- a/bridge/vlan.c
+++ b/bridge/vlan.c
@@ -920,6 +920,16 @@ static void print_vlan_global_opts(struct rtattr *a, int ifindex)
 		print_uint(PRINT_ANY, "msti", "msti %u ",
 			   rta_getattr_u16(vattr));
 	}
+	if (vtb[BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V4]) {
+		vattr = vtb[BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V4];
+		print_uint(PRINT_ANY, "mcast_active_v4", "mcast_active_v4 %u ",
+			   rta_getattr_u8(vattr));
+	}
+	if (vtb[BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V6]) {
+		vattr = vtb[BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V6];
+		print_uint(PRINT_ANY, "mcast_active_v6", "mcast_active_v6 %u ",
+			   rta_getattr_u8(vattr));
+	}
 	print_nl();
 	if (vtb[BRIDGE_VLANDB_GOPTS_MCAST_ROUTER_PORTS]) {
 		vattr = RTA_DATA(vtb[BRIDGE_VLANDB_GOPTS_MCAST_ROUTER_PORTS]);
diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 4d7509c4b84d..be0935057c56 100644
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -584,6 +584,8 @@ enum {
 	BRIDGE_VLANDB_GOPTS_MCAST_ROUTER_PORTS,
 	BRIDGE_VLANDB_GOPTS_MCAST_QUERIER_STATE,
 	BRIDGE_VLANDB_GOPTS_MSTI,
+	BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V4,
+	BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V6,
 	__BRIDGE_VLANDB_GOPTS_MAX
 };
 #define BRIDGE_VLANDB_GOPTS_MAX (__BRIDGE_VLANDB_GOPTS_MAX - 1)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index d05f5cc750ff..7d36cfd6b30c 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -794,6 +794,8 @@ enum {
 	IFLA_BR_MCAST_QUERIER_STATE,
 	IFLA_BR_FDB_N_LEARNED,
 	IFLA_BR_FDB_MAX_LEARNED,
+	IFLA_BR_MCAST_ACTIVE_V4,
+	IFLA_BR_MCAST_ACTIVE_V6,
 	__IFLA_BR_MAX,
 };
 
diff --git a/ip/iplink_bridge.c b/ip/iplink_bridge.c
index df3264c3f45d..b3c0d6bb5310 100644
--- a/ip/iplink_bridge.c
+++ b/ip/iplink_bridge.c
@@ -784,6 +784,18 @@ static void bridge_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 			   "mcast_mld_version %u ",
 			   rta_getattr_u8(tb[IFLA_BR_MCAST_MLD_VERSION]));
 
+	if (tb[IFLA_BR_MCAST_ACTIVE_V4])
+		print_uint(PRINT_ANY,
+			   "mcast_active_v4",
+			   "mcast_active_v4 %u ",
+			   rta_getattr_u8(tb[IFLA_BR_MCAST_ACTIVE_V4]));
+
+	if (tb[IFLA_BR_MCAST_ACTIVE_V6])
+		print_uint(PRINT_ANY,
+			   "mcast_active_v6",
+			   "mcast_active_v6 %u ",
+			   rta_getattr_u8(tb[IFLA_BR_MCAST_ACTIVE_V6]));
+
 	if (tb[IFLA_BR_NF_CALL_IPTABLES])
 		print_uint(PRINT_ANY,
 			   "nf_call_iptables",
-- 
2.51.0

Re: [PATCH iproute2-next] bridge: mcast: add mcast_active_v4 / mcast_active_v6 output

[Ido Schimmel]

On Fri, Feb 06, 2026 at 03:37:04AM +0100, Linus Lüssing wrote:
> Add output for the mcast_active_v4 and mcast_active_v6 states. If their
> output is 1 then IGMP/MLD snooping is applied to multicast payload
> traffic of their according protocol family. This is the case when:
> 
> * the bridge interface is up
> * multicast snooping is enabled
> * an IGMP/MLD querier is present
> * for own IPv6 MLD querier: an IPv6 address is configured on the bridge
> 
> Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
> ---
>  bridge/vlan.c                  | 10 ++++++++++
>  include/uapi/linux/if_bridge.h |  2 ++
>  include/uapi/linux/if_link.h   |  2 ++

Code looks fine, but note that David asks to split the uAPI header
changes to a separate patch as a hint for him to sync the headers. See
commit a3ec2778576b ("Update kernel headers") for example.

>  ip/iplink_bridge.c             | 12 ++++++++++++
>  4 files changed, 26 insertions(+)