Merge branch 'net-bridge-multicast-per-port-eht-hosts-limit'

Nikolay Aleksandrov says:

====================
net: bridge: multicast: per-port EHT hosts limit

This set adds a simple configurable per-port EHT tracked hosts limit.
Patch 01 adds a default limit of 512 tracked hosts per-port, since the EHT
changes are still only in net-next that shouldn't be a problem. Then
patch 02 adds the ability to configure and retrieve the hosts limit
and to retrieve the current number of tracked hosts per port.
Let's be on the safe side and limit the number of tracked hosts by
default while allowing the user to increase that limit if needed.
====================

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

include/uapi/linux/if_link.h

···
 	IFLA_BRPORT_BACKUP_PORT,
 	IFLA_BRPORT_MRP_RING_OPEN,
 	IFLA_BRPORT_MRP_IN_OPEN,
+	IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT,
+	IFLA_BRPORT_MCAST_EHT_HOSTS_CNT,
 	__IFLA_BRPORT_MAX
 };
 #define IFLA_BRPORT_MAX (__IFLA_BRPORT_MAX - 1)

net/bridge/br_multicast.c

···
 int br_multicast_add_port(struct net_bridge_port *port)
 {
 	port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
+	port->multicast_eht_hosts_limit = BR_MCAST_DEFAULT_EHT_HOSTS_LIMIT;
 
 	timer_setup(&port->multicast_router_timer,
 		    br_multicast_router_expired, 0);

net/bridge/br_multicast_eht.c

···
 {
 	WARN_ON(!hlist_empty(&eht_host->set_entries));
 
+	br_multicast_eht_hosts_dec(eht_host->pg);
+
 	rb_erase(&eht_host->rb_node, &eht_host->pg->eht_host_tree);
 	RB_CLEAR_NODE(&eht_host->rb_node);
 	kfree(eht_host);
···
 			return this;
 	}
 
+	if (br_multicast_eht_hosts_over_limit(pg))
+		return NULL;
+
 	eht_host = kzalloc(sizeof(*eht_host), GFP_ATOMIC);
 	if (!eht_host)
 		return NULL;
···
 
 	rb_link_node(&eht_host->rb_node, parent, link);
 	rb_insert_color(&eht_host->rb_node, &pg->eht_host_tree);
+
+	br_multicast_eht_hosts_inc(pg);
 
 	return eht_host;
 }
···
 
 out:
 	return changed;
+}
+
+int br_multicast_eht_set_hosts_limit(struct net_bridge_port *p,
+				     u32 eht_hosts_limit)
+{
+	struct net_bridge *br = p->br;
+
+	if (!eht_hosts_limit)
+		return -EINVAL;
+
+	spin_lock_bh(&br->multicast_lock);
+	p->multicast_eht_hosts_limit = eht_hosts_limit;
+	spin_unlock_bh(&br->multicast_lock);
+
+	return 0;
 }

net/bridge/br_netlink.c

···
 #include "br_private_stp.h"
 #include "br_private_cfm.h"
 #include "br_private_tunnel.h"
+#include "br_private_mcast_eht.h"
 
 static int __get_num_vlan_infos(struct net_bridge_vlan_group *vg,
 				u32 filter_mask)
···
 		+ nla_total_size(sizeof(u16))	/* IFLA_BRPORT_GROUP_FWD_MASK */
 		+ nla_total_size(sizeof(u8))	/* IFLA_BRPORT_MRP_RING_OPEN */
 		+ nla_total_size(sizeof(u8))	/* IFLA_BRPORT_MRP_IN_OPEN */
+		+ nla_total_size(sizeof(u32))	/* IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT */
+		+ nla_total_size(sizeof(u32))	/* IFLA_BRPORT_MCAST_EHT_HOSTS_CNT */
 		+ 0;
 }
 
···
 
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 	if (nla_put_u8(skb, IFLA_BRPORT_MULTICAST_ROUTER,
-		       p->multicast_router))
+		       p->multicast_router) ||
+	    nla_put_u32(skb, IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT,
+			p->multicast_eht_hosts_limit) ||
+	    nla_put_u32(skb, IFLA_BRPORT_MCAST_EHT_HOSTS_CNT,
+			p->multicast_eht_hosts_cnt))
 		return -EMSGSIZE;
 #endif
 
···
 	[IFLA_BRPORT_NEIGH_SUPPRESS] = { .type = NLA_U8 },
 	[IFLA_BRPORT_ISOLATED]	= { .type = NLA_U8 },
 	[IFLA_BRPORT_BACKUP_PORT] = { .type = NLA_U32 },
+	[IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT] = { .type = NLA_U32 },
 };
 
 /* Change the state of the port and notify spanning tree */
···
 		u8 mcast_router = nla_get_u8(tb[IFLA_BRPORT_MULTICAST_ROUTER]);
 
 		err = br_multicast_set_port_router(p, mcast_router);
+		if (err)
+			return err;
+	}
+
+	if (tb[IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT]) {
+		u32 hlimit;
+
+		hlimit = nla_get_u32(tb[IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT]);
+		err = br_multicast_eht_set_hosts_limit(p, hlimit);
 		if (err)
 			return err;
 	}

net/bridge/br_private.h

···
 #if IS_ENABLED(CONFIG_IPV6)
 	struct bridge_mcast_own_query	ip6_own_query;
 #endif /* IS_ENABLED(CONFIG_IPV6) */
+	u32				multicast_eht_hosts_limit;
+	u32				multicast_eht_hosts_cnt;
 	unsigned char			multicast_router;
 	struct bridge_mcast_stats	__percpu *mcast_stats;
 	struct timer_list		multicast_router_timer;

net/bridge/br_private_mcast_eht.h

···
 #ifndef _BR_PRIVATE_MCAST_EHT_H_
 #define _BR_PRIVATE_MCAST_EHT_H_
 
+#define BR_MCAST_DEFAULT_EHT_HOSTS_LIMIT 512
+
 union net_bridge_eht_addr {
 	__be32				ip4;
 #if IS_ENABLED(CONFIG_IPV6)
···
 	struct net_bridge_mcast_gc	mcast_gc;
 };
 
+#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 void br_multicast_eht_clean_sets(struct net_bridge_port_group *pg);
 bool br_multicast_eht_handle(struct net_bridge_port_group *pg,
 			     void *h_addr,
···
 			     u32 nsrcs,
 			     size_t addr_size,
 			     int grec_type);
+int br_multicast_eht_set_hosts_limit(struct net_bridge_port *p,
+				     u32 eht_hosts_limit);
 
 static inline bool
 br_multicast_eht_should_del_pg(const struct net_bridge_port_group *pg)
···
 	return !!((pg->key.port->flags & BR_MULTICAST_FAST_LEAVE) &&
 		  RB_EMPTY_ROOT(&pg->eht_host_tree));
 }
+
+static inline bool
+br_multicast_eht_hosts_over_limit(const struct net_bridge_port_group *pg)
+{
+	const struct net_bridge_port *p = pg->key.port;
+
+	return !!(p->multicast_eht_hosts_cnt >= p->multicast_eht_hosts_limit);
+}
+
+static inline void br_multicast_eht_hosts_inc(struct net_bridge_port_group *pg)
+{
+	struct net_bridge_port *p = pg->key.port;
+
+	p->multicast_eht_hosts_cnt++;
+}
+
+static inline void br_multicast_eht_hosts_dec(struct net_bridge_port_group *pg)
+{
+	struct net_bridge_port *p = pg->key.port;
+
+	p->multicast_eht_hosts_cnt--;
+}
+#endif /* CONFIG_BRIDGE_IGMP_SNOOPING */
 
 #endif /* _BR_PRIVATE_MCAST_EHT_H_ */

net/bridge/br_sysfs_if.c

···
 #include <linux/sched/signal.h>
 
 #include "br_private.h"
+#include "br_private_mcast_eht.h"
 
 struct brport_attribute {
 	struct attribute	attr;
···
 static BRPORT_ATTR(multicast_router, 0644, show_multicast_router,
 		   store_multicast_router);
 
+static ssize_t show_multicast_eht_hosts_limit(struct net_bridge_port *p,
+					      char *buf)
+{
+	return sprintf(buf, "%u\n", p->multicast_eht_hosts_limit);
+}
+
+static int store_multicast_eht_hosts_limit(struct net_bridge_port *p,
+					   unsigned long v)
+{
+	return br_multicast_eht_set_hosts_limit(p, v);
+}
+static BRPORT_ATTR(multicast_eht_hosts_limit, 0644,
+		   show_multicast_eht_hosts_limit,
+		   store_multicast_eht_hosts_limit);
+
+static ssize_t show_multicast_eht_hosts_cnt(struct net_bridge_port *p,
+					    char *buf)
+{
+	return sprintf(buf, "%u\n", p->multicast_eht_hosts_cnt);
+}
+static BRPORT_ATTR(multicast_eht_hosts_cnt, 0444, show_multicast_eht_hosts_cnt,
+		   NULL);
+
 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
 #endif
···
 	&brport_attr_multicast_router,
 	&brport_attr_multicast_fast_leave,
 	&brport_attr_multicast_to_unicast,
+	&brport_attr_multicast_eht_hosts_limit,
+	&brport_attr_multicast_eht_hosts_cnt,
 #endif
 	&brport_attr_proxyarp,
 	&brport_attr_proxyarp_wifi,

net/core/rtnetlink.c

···
 #include <net/net_namespace.h>
 
 #define RTNL_MAX_TYPE		50
-#define RTNL_SLAVE_MAX_TYPE	36
+#define RTNL_SLAVE_MAX_TYPE	40
 
 struct rtnl_link {
 	rtnl_doit_func		doit;