2 files changed, 95 insertions, 13 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 5ccac62b4005..b3f17c9b4d06 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -789,6 +789,18 @@ static void br_ip6_multicast_querier_expired(unsigned long data)
 }
 #endif
 
+static void br_multicast_select_own_querier(struct net_bridge *br,
+                                            struct br_ip *ip,
+                                            struct sk_buff *skb)
+{
+        if (ip->proto == htons(ETH_P_IP))
+                br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
+#if IS_ENABLED(CONFIG_IPV6)
+        else
+                br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
+#endif
+}
+
 static void __br_multicast_send_query(struct net_bridge *br,
                                       struct net_bridge_port *port,
                                       struct br_ip *ip)
@@ -804,8 +816,10 @@ static void __br_multicast_send_query(struct net_bridge *br,
                 skb->dev = port->dev;
                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
                         dev_queue_xmit);
-        } else
+        } else {
+                br_multicast_select_own_querier(br, ip, skb);
                 netif_rx(skb);
+        }
 }
 
 static void br_multicast_send_query(struct net_bridge *br,
@@ -1065,6 +1079,62 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 }
 #endif
 
+static bool br_ip4_multicast_select_querier(struct net_bridge *br,
+                                            __be32 saddr)
+{
+        if (!timer_pending(&br->ip4_own_query.timer) &&
+            !timer_pending(&br->ip4_other_query.timer))
+                goto update;
+
+        if (!br->ip4_querier.addr.u.ip4)
+                goto update;
+
+        if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
+                goto update;
+
+        return false;
+
+update:
+        br->ip4_querier.addr.u.ip4 = saddr;
+
+        return true;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static bool br_ip6_multicast_select_querier(struct net_bridge *br,
+                                            struct in6_addr *saddr)
+{
+        if (!timer_pending(&br->ip6_own_query.timer) &&
+            !timer_pending(&br->ip6_other_query.timer))
+                goto update;
+
+        if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
+                goto update;
+
+        return false;
+
+update:
+        br->ip6_querier.addr.u.ip6 = *saddr;
+
+        return true;
+}
+#endif
+
+static bool br_multicast_select_querier(struct net_bridge *br,
+                                        struct br_ip *saddr)
+{
+        switch (saddr->proto) {
+        case htons(ETH_P_IP):
+                return br_ip4_multicast_select_querier(br, saddr->u.ip4);
+#if IS_ENABLED(CONFIG_IPV6)
+        case htons(ETH_P_IPV6):
+                return br_ip6_multicast_select_querier(br, &saddr->u.ip6);
+#endif
+        }
+
+        return false;
+}
+
 static void
 br_multicast_update_query_timer(struct net_bridge *br,
                                 struct bridge_mcast_other_query *query,
@@ -1127,15 +1197,13 @@ timer:
 static void br_multicast_query_received(struct net_bridge *br,
                                         struct net_bridge_port *port,
                                         struct bridge_mcast_other_query *query,
-                                        int saddr,
-                                        bool is_general_query,
+                                        struct br_ip *saddr,
                                         unsigned long max_delay)
 {
-        if (saddr && is_general_query)
-                br_multicast_update_query_timer(br, query, max_delay);
-        else if (timer_pending(&query->timer))
+        if (!br_multicast_select_querier(br, saddr))
                 return;
 
+        br_multicast_update_query_timer(br, query, max_delay);
         br_multicast_mark_router(br, port);
 }
 
@@ -1150,6 +1218,7 @@ static int br_ip4_multicast_query(struct net_bridge *br,
         struct igmpv3_query *ih3;
         struct net_bridge_port_group *p;
         struct net_bridge_port_group __rcu **pp;
+        struct br_ip saddr;
         unsigned long max_delay;
         unsigned long now = jiffies;
         __be32 group;
@@ -1191,11 +1260,14 @@ static int br_ip4_multicast_query(struct net_bridge *br,
                 goto out;
         }
 
-        br_multicast_query_received(br, port, &br->ip4_other_query,
-                                    !!iph->saddr, !group, max_delay);
+        if (!group) {
+                saddr.proto = htons(ETH_P_IP);
+                saddr.u.ip4 = iph->saddr;
 
-        if (!group)
+                br_multicast_query_received(br, port, &br->ip4_other_query,
+                                            &saddr, max_delay);
                 goto out;
+        }
 
         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
         if (!mp)
@@ -1235,6 +1307,7 @@ static int br_ip6_multicast_query(struct net_bridge *br,
         struct mld2_query *mld2q;
         struct net_bridge_port_group *p;
         struct net_bridge_port_group __rcu **pp;
+        struct br_ip saddr;
         unsigned long max_delay;
         unsigned long now = jiffies;
         const struct in6_addr *group = NULL;
@@ -1283,12 +1356,14 @@ static int br_ip6_multicast_query(struct net_bridge *br,
                 goto out;
         }
 
-        br_multicast_query_received(br, port, &br->ip6_other_query,
-                                    !ipv6_addr_any(&ip6h->saddr),
-                                    is_general_query, max_delay);
+        if (is_general_query) {
+                saddr.proto = htons(ETH_P_IPV6);
+                saddr.u.ip6 = ip6h->saddr;
 
-        if (!group)
+                br_multicast_query_received(br, port, &br->ip6_other_query,
+                                            &saddr, max_delay);
                 goto out;
+        }
 
         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
         if (!mp)
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 2469aeeda1ec..97c5e46dde72 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -78,6 +78,11 @@ struct bridge_mcast_other_query {
         struct timer_list               timer;
         unsigned long                   delay_time;
 };
+
+/* selected querier */
+struct bridge_mcast_querier {
+        struct br_ip addr;
+};
 #endif
 
 struct net_port_vlans {
@@ -284,9 +289,11 @@ struct net_bridge
         struct timer_list               multicast_router_timer;
         struct bridge_mcast_other_query ip4_other_query;
         struct bridge_mcast_own_query   ip4_own_query;
+        struct bridge_mcast_querier     ip4_querier;
 #if IS_ENABLED(CONFIG_IPV6)
         struct bridge_mcast_other_query ip6_other_query;
         struct bridge_mcast_own_query   ip6_own_query;
+        struct bridge_mcast_querier     ip6_querier;
 #endif /* IS_ENABLED(CONFIG_IPV6) */
 #endif