[PATCH net-next v4 01/14] net: bridge: mcast: export ip{4,6}_active state to netlink

Linus Lüssing
2026-03-07T04:46:11Z

Export the new ip{4,6}_active variables to netlink, to be able to
check from userspace that they are updated as intended.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
---
include/uapi/linux/if_bridge.h | 2 ++
include/uapi/linux/if_link.h | 12 ++++++++++++
net/bridge/br_netlink.c | 20 +++++++++++++++++++-
net/bridge/br_private.h | 2 +-
net/bridge/br_vlan_options.c | 25 +++++++++++++++++++++++--
net/core/rtnetlink.c | 2 +-
6 files changed, 58 insertions(+), 5 deletions(-)

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index e52f8207ab27..910103b1ef03 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 83a96c56b8ca..66c59953d301 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -744,6 +744,16 @@ enum in6_addr_gen_mode {
* @IFLA_BR_FDB_MAX_LEARNED
* Set the number of max dynamically learned FDB entries for the current
* bridge.
+ *
+ * @IFLA_BR_MCAST_ACTIVE_V4
+ * Bridge IPv4 mcast active state, read only.
+ *
+ * 1 if an IGMP querier is present, 0 otherwise.
+ *
+ * @IFLA_BR_MCAST_ACTIVE_V6
+ * Bridge IPv6 mcast active state, read only.
+ *
+ * 1 if an MLD querier is present, 0 otherwise.
*/
enum {
IFLA_BR_UNSPEC,
@@ -796,6 +806,8 @@ 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/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 0264730938f4..7fff59c3bf76 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -1264,7 +1264,9 @@ static const struct nla_policy br_policy[IFLA_BR_MAX + 1] = {
[IFLA_BR_VLAN_STATS_ENABLED] = { .type = NLA_U8 },
[IFLA_BR_MCAST_STATS_ENABLED] = { .type = NLA_U8 },
[IFLA_BR_MCAST_IGMP_VERSION] = { .type = NLA_U8 },
+ [IFLA_BR_MCAST_ACTIVE_V4] = { .type = NLA_REJECT },
[IFLA_BR_MCAST_MLD_VERSION] = { .type = NLA_U8 },
+ [IFLA_BR_MCAST_ACTIVE_V6] = { .type = NLA_REJECT },
[IFLA_BR_VLAN_STATS_PER_PORT] = { .type = NLA_U8 },
[IFLA_BR_MULTI_BOOLOPT] =
NLA_POLICY_EXACT_LEN(sizeof(struct br_boolopt_multi)),
@@ -1625,7 +1627,9 @@ static size_t br_get_size(const struct net_device *brdev)
nla_total_size_64bit(sizeof(u64)) + /* IFLA_BR_MCAST_QUERY_RESPONSE_INTVL */
nla_total_size_64bit(sizeof(u64)) + /* IFLA_BR_MCAST_STARTUP_QUERY_INTVL */
nla_total_size(sizeof(u8)) + /* IFLA_BR_MCAST_IGMP_VERSION */
+ nla_total_size(sizeof(u8)) + /* IFLA_BR_MCAST_ACTIVE_V4 */
nla_total_size(sizeof(u8)) + /* IFLA_BR_MCAST_MLD_VERSION */
+ nla_total_size(sizeof(u8)) + /* IFLA_BR_MCAST_ACTIVE_V6 */
br_multicast_querier_state_size() + /* IFLA_BR_MCAST_QUERIER_STATE */
#endif
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
@@ -1639,6 +1643,8 @@ static size_t br_get_size(const struct net_device *brdev)

static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev)
{
+ struct ethhdr eth6 __maybe_unused = { .h_proto = htons(ETH_P_IPV6) };
+ struct ethhdr eth4 __maybe_unused = { .h_proto = htons(ETH_P_IP) };
struct net_bridge *br = netdev_priv(brdev);
u32 forward_delay = jiffies_to_clock_t(br->forward_delay);
u32 hello_time = jiffies_to_clock_t(br->hello_time);
@@ -1717,12 +1723,24 @@ static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev)
br->multicast_ctx.multicast_startup_query_count) ||
nla_put_u8(skb, IFLA_BR_MCAST_IGMP_VERSION,
br->multicast_ctx.multicast_igmp_version) ||
+ nla_put_u8(skb, IFLA_BR_MCAST_ACTIVE_V4,
+ netif_running(brdev) &&
+ br_opt_get(br, BROPT_MULTICAST_ENABLED) &&
+ !br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED) &&
+ br_multicast_querier_exists(&br->multicast_ctx, &eth4,
+ NULL)) ||
br_multicast_dump_querier_state(skb, &br->multicast_ctx,
IFLA_BR_MCAST_QUERIER_STATE))
return -EMSGSIZE;
#if IS_ENABLED(CONFIG_IPV6)
if (nla_put_u8(skb, IFLA_BR_MCAST_MLD_VERSION,
- br->multicast_ctx.multicast_mld_version))
+ br->multicast_ctx.multicast_mld_version) ||
+ nla_put_u8(skb, IFLA_BR_MCAST_ACTIVE_V6,
+ netif_running(brdev) &&
+ br_opt_get(br, BROPT_MULTICAST_ENABLED) &&
+ !br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED) &&
+ br_multicast_querier_exists(&br->multicast_ctx, &eth6,
+ NULL)))
return -EMSGSIZE;
#endif
clockval = jiffies_to_clock_t(br->multicast_ctx.multicast_last_member_interval);
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 9b55d38ea9ed..545be319b6cb 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1902,7 +1902,7 @@ int br_vlan_rtm_process_global_options(struct net_device *dev,
bool br_vlan_global_opts_can_enter_range(const struct net_bridge_vlan *v_curr,
const struct net_bridge_vlan *r_end);
bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range,
- const struct net_bridge_vlan *v_opts);
+ struct net_bridge_vlan *v_opts);

/* vlan state manipulation helpers using *_ONCE to annotate lock-free access,
* while br_vlan_set_state() may access data protected by multicast_lock.
diff --git a/net/bridge/br_vlan_options.c b/net/bridge/br_vlan_options.c
index 5514e1fc8d1f..06045d68a2d1 100644
--- a/net/bridge/br_vlan_options.c
+++ b/net/bridge/br_vlan_options.c
@@ -367,10 +367,13 @@ bool br_vlan_global_opts_can_enter_range(const struct net_bridge_vlan *v_curr,
}

bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range,
- const struct net_bridge_vlan *v_opts)
+ struct net_bridge_vlan *v_opts)
{
+ struct ethhdr eth6 __maybe_unused = { .h_proto = htons(ETH_P_IPV6) };
+ struct ethhdr eth4 __maybe_unused = { .h_proto = htons(ETH_P_IP) };
struct nlattr *nest2 __maybe_unused;
u64 clockval __maybe_unused;
+ bool mcact __maybe_unused;
struct nlattr *nest;

nest = nla_nest_start(skb, BRIDGE_VLANDB_GLOBAL_OPTIONS);
@@ -385,10 +388,17 @@ bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range,
goto out_err;

#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
+ mcact = netif_running(v_opts->br->dev) &&
+ br_opt_get(v_opts->br, BROPT_MULTICAST_ENABLED) &&
+ br_opt_get(v_opts->br, BROPT_MCAST_VLAN_SNOOPING_ENABLED) &&
+ !br_multicast_ctx_vlan_global_disabled(&v_opts->br_mcast_ctx) &&
+ br_multicast_querier_exists(&v_opts->br_mcast_ctx, &eth4, NULL);
+
if (nla_put_u8(skb, BRIDGE_VLANDB_GOPTS_MCAST_SNOOPING,
!!(v_opts->priv_flags & BR_VLFLAG_GLOBAL_MCAST_ENABLED)) ||
nla_put_u8(skb, BRIDGE_VLANDB_GOPTS_MCAST_IGMP_VERSION,
v_opts->br_mcast_ctx.multicast_igmp_version) ||
+ nla_put_u8(skb, BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V4, mcact) ||
nla_put_u32(skb, BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_CNT,
v_opts->br_mcast_ctx.multicast_last_member_count) ||
nla_put_u32(skb, BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_CNT,
@@ -442,8 +452,15 @@ bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range,
}

#if IS_ENABLED(CONFIG_IPV6)
+ mcact = netif_running(v_opts->br->dev) &&
+ br_opt_get(v_opts->br, BROPT_MULTICAST_ENABLED) &&
+ br_opt_get(v_opts->br, BROPT_MCAST_VLAN_SNOOPING_ENABLED) &&
+ !br_multicast_ctx_vlan_global_disabled(&v_opts->br_mcast_ctx) &&
+ br_multicast_querier_exists(&v_opts->br_mcast_ctx, &eth6, NULL);
+
if (nla_put_u8(skb, BRIDGE_VLANDB_GOPTS_MCAST_MLD_VERSION,
- v_opts->br_mcast_ctx.multicast_mld_version))
+ v_opts->br_mcast_ctx.multicast_mld_version) ||
+ nla_put_u8(skb, BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V6, mcact))
goto out_err;
#endif
#endif
@@ -468,7 +485,9 @@ static size_t rtnl_vlan_global_opts_nlmsg_size(const struct net_bridge_vlan *v)
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
+ nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_GOPTS_MCAST_SNOOPING */
+ nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_GOPTS_MCAST_IGMP_VERSION */
+ + nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V4 */
+ nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_GOPTS_MCAST_MLD_VERSION */
+ + nla_total_size(sizeof(u8)) /* BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V6 */
+ nla_total_size(sizeof(u32)) /* BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_CNT */
+ nla_total_size(sizeof(u32)) /* BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_CNT */
+ nla_total_size(sizeof(u64)) /* BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_INTVL */
@@ -650,9 +669,11 @@ static const struct nla_policy br_vlan_db_gpol[BRIDGE_VLANDB_GOPTS_MAX + 1] = {
[BRIDGE_VLANDB_GOPTS_RANGE] = { .type = NLA_U16 },
[BRIDGE_VLANDB_GOPTS_MCAST_SNOOPING] = { .type = NLA_U8 },
[BRIDGE_VLANDB_GOPTS_MCAST_MLD_VERSION] = { .type = NLA_U8 },
+ [BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V6] = { .type = NLA_REJECT },
[BRIDGE_VLANDB_GOPTS_MCAST_QUERY_INTVL] = { .type = NLA_U64 },
[BRIDGE_VLANDB_GOPTS_MCAST_QUERIER] = { .type = NLA_U8 },
[BRIDGE_VLANDB_GOPTS_MCAST_IGMP_VERSION] = { .type = NLA_U8 },
+ [BRIDGE_VLANDB_GOPTS_MCAST_ACTIVE_V4] = { .type = NLA_REJECT },
[BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_CNT] = { .type = NLA_U32 },
[BRIDGE_VLANDB_GOPTS_MCAST_STARTUP_QUERY_CNT] = { .type = NLA_U32 },
[BRIDGE_VLANDB_GOPTS_MCAST_LAST_MEMBER_INTVL] = { .type = NLA_U64 },
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index dad4b1054955..8febe7475f1f 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -62,7 +62,7 @@

#include "dev.h"

-#define RTNL_MAX_TYPE 50
+#define RTNL_MAX_TYPE 52
#define RTNL_SLAVE_MAX_TYPE 44

struct rtnl_link {
--
2.53.0