root/net/bridge/br_mdb.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/err.h>
#include <linux/igmp.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rculist.h>
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <net/ip.h>
#include <net/netlink.h>
#include <net/switchdev.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#include <net/addrconf.h>
#endif

#include "br_private.h"

static bool
br_ip4_rports_get_timer(struct net_bridge_mcast_port *pmctx,
                        unsigned long *timer)
{
        *timer = br_timer_value(&pmctx->ip4_mc_router_timer);
        return !hlist_unhashed(&pmctx->ip4_rlist);
}

static bool
br_ip6_rports_get_timer(struct net_bridge_mcast_port *pmctx,
                        unsigned long *timer)
{
#if IS_ENABLED(CONFIG_IPV6)
        *timer = br_timer_value(&pmctx->ip6_mc_router_timer);
        return !hlist_unhashed(&pmctx->ip6_rlist);
#else
        *timer = 0;
        return false;
#endif
}

static size_t __br_rports_one_size(void)
{
        return nla_total_size(sizeof(u32)) + /* MDBA_ROUTER_PORT */
               nla_total_size(sizeof(u32)) + /* MDBA_ROUTER_PATTR_TIMER */
               nla_total_size(sizeof(u8)) +  /* MDBA_ROUTER_PATTR_TYPE */
               nla_total_size(sizeof(u32)) + /* MDBA_ROUTER_PATTR_INET_TIMER */
               nla_total_size(sizeof(u32)) + /* MDBA_ROUTER_PATTR_INET6_TIMER */
               nla_total_size(sizeof(u32));  /* MDBA_ROUTER_PATTR_VID */
}

size_t br_rports_size(const struct net_bridge_mcast *brmctx)
{
        struct net_bridge_mcast_port *pmctx;
        size_t size = nla_total_size(0); /* MDBA_ROUTER */

        rcu_read_lock();
        hlist_for_each_entry_rcu(pmctx, &brmctx->ip4_mc_router_list,
                                 ip4_rlist)
                size += __br_rports_one_size();

#if IS_ENABLED(CONFIG_IPV6)
        hlist_for_each_entry_rcu(pmctx, &brmctx->ip6_mc_router_list,
                                 ip6_rlist)
                size += __br_rports_one_size();
#endif
        rcu_read_unlock();

        return size;
}

int br_rports_fill_info(struct sk_buff *skb,
                        const struct net_bridge_mcast *brmctx)
{
        u16 vid = brmctx->vlan ? brmctx->vlan->vid : 0;
        bool have_ip4_mc_rtr, have_ip6_mc_rtr;
        unsigned long ip4_timer, ip6_timer;
        struct nlattr *nest, *port_nest;
        struct net_bridge_port *p;

        if (!brmctx->multicast_router || !br_rports_have_mc_router(brmctx))
                return 0;

        nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
        if (nest == NULL)
                return -EMSGSIZE;

        list_for_each_entry_rcu(p, &brmctx->br->port_list, list) {
                struct net_bridge_mcast_port *pmctx;

                if (vid) {
                        struct net_bridge_vlan *v;

                        v = br_vlan_find(nbp_vlan_group(p), vid);
                        if (!v)
                                continue;
                        pmctx = &v->port_mcast_ctx;
                } else {
                        pmctx = &p->multicast_ctx;
                }

                have_ip4_mc_rtr = br_ip4_rports_get_timer(pmctx, &ip4_timer);
                have_ip6_mc_rtr = br_ip6_rports_get_timer(pmctx, &ip6_timer);

                if (!have_ip4_mc_rtr && !have_ip6_mc_rtr)
                        continue;

                port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
                if (!port_nest)
                        goto fail;

                if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
                    nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
                                max(ip4_timer, ip6_timer)) ||
                    nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
                               p->multicast_ctx.multicast_router) ||
                    (have_ip4_mc_rtr &&
                     nla_put_u32(skb, MDBA_ROUTER_PATTR_INET_TIMER,
                                 ip4_timer)) ||
                    (have_ip6_mc_rtr &&
                     nla_put_u32(skb, MDBA_ROUTER_PATTR_INET6_TIMER,
                                 ip6_timer)) ||
                    (vid && nla_put_u16(skb, MDBA_ROUTER_PATTR_VID, vid))) {
                        nla_nest_cancel(skb, port_nest);
                        goto fail;
                }
                nla_nest_end(skb, port_nest);
        }

        nla_nest_end(skb, nest);
        return 0;
fail:
        nla_nest_cancel(skb, nest);
        return -EMSGSIZE;
}

static void __mdb_entry_fill_flags(struct br_mdb_entry *e, unsigned char flags)
{
        e->state = flags & MDB_PG_FLAGS_PERMANENT;
        e->flags = 0;
        if (flags & MDB_PG_FLAGS_OFFLOAD)
                e->flags |= MDB_FLAGS_OFFLOAD;
        if (flags & MDB_PG_FLAGS_FAST_LEAVE)
                e->flags |= MDB_FLAGS_FAST_LEAVE;
        if (flags & MDB_PG_FLAGS_STAR_EXCL)
                e->flags |= MDB_FLAGS_STAR_EXCL;
        if (flags & MDB_PG_FLAGS_BLOCKED)
                e->flags |= MDB_FLAGS_BLOCKED;
        if (flags & MDB_PG_FLAGS_OFFLOAD_FAILED)
                e->flags |= MDB_FLAGS_OFFLOAD_FAILED;
}

static void __mdb_entry_to_br_ip(struct br_mdb_entry *entry, struct br_ip *ip,
                                 struct nlattr **mdb_attrs)
{
        memset(ip, 0, sizeof(struct br_ip));
        ip->vid = entry->vid;
        ip->proto = entry->addr.proto;
        switch (ip->proto) {
        case htons(ETH_P_IP):
                ip->dst.ip4 = entry->addr.u.ip4;
                if (mdb_attrs && mdb_attrs[MDBE_ATTR_SOURCE])
                        ip->src.ip4 = nla_get_in_addr(mdb_attrs[MDBE_ATTR_SOURCE]);
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case htons(ETH_P_IPV6):
                ip->dst.ip6 = entry->addr.u.ip6;
                if (mdb_attrs && mdb_attrs[MDBE_ATTR_SOURCE])
                        ip->src.ip6 = nla_get_in6_addr(mdb_attrs[MDBE_ATTR_SOURCE]);
                break;
#endif
        default:
                ether_addr_copy(ip->dst.mac_addr, entry->addr.u.mac_addr);
        }

}

static int __mdb_fill_srcs(struct sk_buff *skb,
                           struct net_bridge_port_group *p)
{
        struct net_bridge_group_src *ent;
        struct nlattr *nest, *nest_ent;

        if (hlist_empty(&p->src_list))
                return 0;

        nest = nla_nest_start(skb, MDBA_MDB_EATTR_SRC_LIST);
        if (!nest)
                return -EMSGSIZE;

        hlist_for_each_entry_rcu(ent, &p->src_list, node,
                                 lockdep_is_held(&p->key.port->br->multicast_lock)) {
                nest_ent = nla_nest_start(skb, MDBA_MDB_SRCLIST_ENTRY);
                if (!nest_ent)
                        goto out_cancel_err;
                switch (ent->addr.proto) {
                case htons(ETH_P_IP):
                        if (nla_put_in_addr(skb, MDBA_MDB_SRCATTR_ADDRESS,
                                            ent->addr.src.ip4)) {
                                nla_nest_cancel(skb, nest_ent);
                                goto out_cancel_err;
                        }
                        break;
#if IS_ENABLED(CONFIG_IPV6)
                case htons(ETH_P_IPV6):
                        if (nla_put_in6_addr(skb, MDBA_MDB_SRCATTR_ADDRESS,
                                             &ent->addr.src.ip6)) {
                                nla_nest_cancel(skb, nest_ent);
                                goto out_cancel_err;
                        }
                        break;
#endif
                default:
                        nla_nest_cancel(skb, nest_ent);
                        continue;
                }
                if (nla_put_u32(skb, MDBA_MDB_SRCATTR_TIMER,
                                br_timer_value(&ent->timer))) {
                        nla_nest_cancel(skb, nest_ent);
                        goto out_cancel_err;
                }
                nla_nest_end(skb, nest_ent);
        }

        nla_nest_end(skb, nest);

        return 0;

out_cancel_err:
        nla_nest_cancel(skb, nest);
        return -EMSGSIZE;
}

static int __mdb_fill_info(struct sk_buff *skb,
                           struct net_bridge_mdb_entry *mp,
                           struct net_bridge_port_group *p)
{
        bool dump_srcs_mode = false;
        struct timer_list *mtimer;
        struct nlattr *nest_ent;
        struct br_mdb_entry e;
        u8 flags = 0;
        int ifindex;

        memset(&e, 0, sizeof(e));
        if (p) {
                ifindex = p->key.port->dev->ifindex;
                mtimer = &p->timer;
                flags = p->flags;
        } else {
                ifindex = mp->br->dev->ifindex;
                mtimer = &mp->timer;
        }

        __mdb_entry_fill_flags(&e, flags);
        e.ifindex = ifindex;
        e.vid = mp->addr.vid;
        if (mp->addr.proto == htons(ETH_P_IP)) {
                e.addr.u.ip4 = mp->addr.dst.ip4;
#if IS_ENABLED(CONFIG_IPV6)
        } else if (mp->addr.proto == htons(ETH_P_IPV6)) {
                e.addr.u.ip6 = mp->addr.dst.ip6;
#endif
        } else {
                ether_addr_copy(e.addr.u.mac_addr, mp->addr.dst.mac_addr);
                e.state = MDB_PERMANENT;
        }
        e.addr.proto = mp->addr.proto;
        nest_ent = nla_nest_start_noflag(skb,
                                         MDBA_MDB_ENTRY_INFO);
        if (!nest_ent)
                return -EMSGSIZE;

        if (nla_put_nohdr(skb, sizeof(e), &e) ||
            nla_put_u32(skb,
                        MDBA_MDB_EATTR_TIMER,
                        br_timer_value(mtimer)))
                goto nest_err;

        switch (mp->addr.proto) {
        case htons(ETH_P_IP):
                dump_srcs_mode = !!(mp->br->multicast_ctx.multicast_igmp_version == 3);
                if (mp->addr.src.ip4) {
                        if (nla_put_in_addr(skb, MDBA_MDB_EATTR_SOURCE,
                                            mp->addr.src.ip4))
                                goto nest_err;
                        break;
                }
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case htons(ETH_P_IPV6):
                dump_srcs_mode = !!(mp->br->multicast_ctx.multicast_mld_version == 2);
                if (!ipv6_addr_any(&mp->addr.src.ip6)) {
                        if (nla_put_in6_addr(skb, MDBA_MDB_EATTR_SOURCE,
                                             &mp->addr.src.ip6))
                                goto nest_err;
                        break;
                }
                break;
#endif
        default:
                ether_addr_copy(e.addr.u.mac_addr, mp->addr.dst.mac_addr);
        }
        if (p) {
                if (nla_put_u8(skb, MDBA_MDB_EATTR_RTPROT, p->rt_protocol))
                        goto nest_err;
                if (dump_srcs_mode &&
                    (__mdb_fill_srcs(skb, p) ||
                     nla_put_u8(skb, MDBA_MDB_EATTR_GROUP_MODE,
                                p->filter_mode)))
                        goto nest_err;
        }
        nla_nest_end(skb, nest_ent);

        return 0;

nest_err:
        nla_nest_cancel(skb, nest_ent);
        return -EMSGSIZE;
}

static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
                            struct net_device *dev)
{
        int idx = 0, s_idx = cb->args[1], err = 0, pidx = 0, s_pidx = cb->args[2];
        struct net_bridge *br = netdev_priv(dev);
        struct net_bridge_mdb_entry *mp;
        struct nlattr *nest, *nest2;

        nest = nla_nest_start_noflag(skb, MDBA_MDB);
        if (nest == NULL)
                return -EMSGSIZE;

        hlist_for_each_entry_rcu(mp, &br->mdb_list, mdb_node) {
                struct net_bridge_port_group *p;
                struct net_bridge_port_group __rcu **pp;

                if (idx < s_idx)
                        goto skip;

                nest2 = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
                if (!nest2) {
                        err = -EMSGSIZE;
                        break;
                }

                if (!s_pidx && mp->host_joined) {
                        err = __mdb_fill_info(skb, mp, NULL);
                        if (err) {
                                nla_nest_cancel(skb, nest2);
                                break;
                        }
                }

                for (pp = &mp->ports; (p = rcu_dereference(*pp)) != NULL;
                      pp = &p->next) {
                        if (!p->key.port)
                                continue;
                        if (pidx < s_pidx)
                                goto skip_pg;

                        err = __mdb_fill_info(skb, mp, p);
                        if (err) {
                                nla_nest_end(skb, nest2);
                                goto out;
                        }
skip_pg:
                        pidx++;
                }
                pidx = 0;
                s_pidx = 0;
                nla_nest_end(skb, nest2);
skip:
                idx++;
        }

out:
        cb->args[1] = idx;
        cb->args[2] = pidx;
        nla_nest_end(skb, nest);
        return err;
}

int br_mdb_dump(struct net_device *dev, struct sk_buff *skb,
                struct netlink_callback *cb)
{
        struct net_bridge *br = netdev_priv(dev);
        struct br_port_msg *bpm;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
                        cb->nlh->nlmsg_seq, RTM_GETMDB, sizeof(*bpm),
                        NLM_F_MULTI);
        if (!nlh)
                return -EMSGSIZE;

        bpm = nlmsg_data(nlh);
        memset(bpm, 0, sizeof(*bpm));
        bpm->ifindex = dev->ifindex;

        rcu_read_lock();

        err = br_mdb_fill_info(skb, cb, dev);
        if (err)
                goto out;
        err = br_rports_fill_info(skb, &br->multicast_ctx);
        if (err)
                goto out;

out:
        rcu_read_unlock();
        nlmsg_end(skb, nlh);
        return err;
}

static int nlmsg_populate_mdb_fill(struct sk_buff *skb,
                                   struct net_device *dev,
                                   struct net_bridge_mdb_entry *mp,
                                   struct net_bridge_port_group *pg,
                                   int type)
{
        struct nlmsghdr *nlh;
        struct br_port_msg *bpm;
        struct nlattr *nest, *nest2;

        nlh = nlmsg_put(skb, 0, 0, type, sizeof(*bpm), 0);
        if (!nlh)
                return -EMSGSIZE;

        bpm = nlmsg_data(nlh);
        memset(bpm, 0, sizeof(*bpm));
        bpm->family  = AF_BRIDGE;
        bpm->ifindex = dev->ifindex;
        nest = nla_nest_start_noflag(skb, MDBA_MDB);
        if (nest == NULL)
                goto cancel;
        nest2 = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
        if (nest2 == NULL)
                goto end;

        if (__mdb_fill_info(skb, mp, pg))
                goto end;

        nla_nest_end(skb, nest2);
        nla_nest_end(skb, nest);
        nlmsg_end(skb, nlh);
        return 0;

end:
        nla_nest_end(skb, nest);
cancel:
        nlmsg_cancel(skb, nlh);
        return -EMSGSIZE;
}

static size_t rtnl_mdb_nlmsg_pg_size(const struct net_bridge_port_group *pg)
{
        struct net_bridge_group_src *ent;
        size_t nlmsg_size, addr_size = 0;

                     /* MDBA_MDB_ENTRY_INFO */
        nlmsg_size = nla_total_size(sizeof(struct br_mdb_entry)) +
                     /* MDBA_MDB_EATTR_TIMER */
                     nla_total_size(sizeof(u32));

        if (!pg)
                goto out;

        /* MDBA_MDB_EATTR_RTPROT */
        nlmsg_size += nla_total_size(sizeof(u8));

        switch (pg->key.addr.proto) {
        case htons(ETH_P_IP):
                /* MDBA_MDB_EATTR_SOURCE */
                if (pg->key.addr.src.ip4)
                        nlmsg_size += nla_total_size(sizeof(__be32));
                if (pg->key.port->br->multicast_ctx.multicast_igmp_version == 2)
                        goto out;
                addr_size = sizeof(__be32);
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case htons(ETH_P_IPV6):
                /* MDBA_MDB_EATTR_SOURCE */
                if (!ipv6_addr_any(&pg->key.addr.src.ip6))
                        nlmsg_size += nla_total_size(sizeof(struct in6_addr));
                if (pg->key.port->br->multicast_ctx.multicast_mld_version == 1)
                        goto out;
                addr_size = sizeof(struct in6_addr);
                break;
#endif
        }

        /* MDBA_MDB_EATTR_GROUP_MODE */
        nlmsg_size += nla_total_size(sizeof(u8));

        /* MDBA_MDB_EATTR_SRC_LIST nested attr */
        if (!hlist_empty(&pg->src_list))
                nlmsg_size += nla_total_size(0);

        hlist_for_each_entry(ent, &pg->src_list, node) {
                /* MDBA_MDB_SRCLIST_ENTRY nested attr +
                 * MDBA_MDB_SRCATTR_ADDRESS + MDBA_MDB_SRCATTR_TIMER
                 */
                nlmsg_size += nla_total_size(0) +
                              nla_total_size(addr_size) +
                              nla_total_size(sizeof(u32));
        }
out:
        return nlmsg_size;
}

static size_t rtnl_mdb_nlmsg_size(const struct net_bridge_port_group *pg)
{
        return NLMSG_ALIGN(sizeof(struct br_port_msg)) +
               /* MDBA_MDB */
               nla_total_size(0) +
               /* MDBA_MDB_ENTRY */
               nla_total_size(0) +
               /* Port group entry */
               rtnl_mdb_nlmsg_pg_size(pg);
}

static void __br_mdb_notify(struct net_device *dev,
                            struct net_bridge_mdb_entry *mp,
                            struct net_bridge_port_group *pg,
                            int type, bool notify_switchdev)
{
        struct net *net = dev_net(dev);
        struct sk_buff *skb;
        int err = -ENOBUFS;

        if (notify_switchdev)
                br_switchdev_mdb_notify(dev, mp, pg, type);

        skb = nlmsg_new(rtnl_mdb_nlmsg_size(pg), GFP_ATOMIC);
        if (!skb)
                goto errout;

        err = nlmsg_populate_mdb_fill(skb, dev, mp, pg, type);
        if (err < 0) {
                kfree_skb(skb);
                goto errout;
        }

        rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC);
        return;
errout:
        rtnl_set_sk_err(net, RTNLGRP_MDB, err);
}

void br_mdb_notify(struct net_device *dev,
                   struct net_bridge_mdb_entry *mp,
                   struct net_bridge_port_group *pg,
                   int type)
{
        __br_mdb_notify(dev, mp, pg, type, true);
}

void br_mdb_flag_change_notify(struct net_device *dev,
                               struct net_bridge_mdb_entry *mp,
                               struct net_bridge_port_group *pg)
{
        __br_mdb_notify(dev, mp, pg, RTM_NEWMDB, false);
}

static int nlmsg_populate_rtr_fill(struct sk_buff *skb,
                                   struct net_device *dev,
                                   int ifindex, u16 vid, u32 pid,
                                   u32 seq, int type, unsigned int flags)
{
        struct nlattr *nest, *port_nest;
        struct br_port_msg *bpm;
        struct nlmsghdr *nlh;

        nlh = nlmsg_put(skb, pid, seq, type, sizeof(*bpm), 0);
        if (!nlh)
                return -EMSGSIZE;

        bpm = nlmsg_data(nlh);
        memset(bpm, 0, sizeof(*bpm));
        bpm->family = AF_BRIDGE;
        bpm->ifindex = dev->ifindex;
        nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
        if (!nest)
                goto cancel;

        port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
        if (!port_nest)
                goto end;
        if (nla_put_nohdr(skb, sizeof(u32), &ifindex)) {
                nla_nest_cancel(skb, port_nest);
                goto end;
        }
        if (vid && nla_put_u16(skb, MDBA_ROUTER_PATTR_VID, vid)) {
                nla_nest_cancel(skb, port_nest);
                goto end;
        }
        nla_nest_end(skb, port_nest);

        nla_nest_end(skb, nest);
        nlmsg_end(skb, nlh);
        return 0;

end:
        nla_nest_end(skb, nest);
cancel:
        nlmsg_cancel(skb, nlh);
        return -EMSGSIZE;
}

static inline size_t rtnl_rtr_nlmsg_size(void)
{
        return NLMSG_ALIGN(sizeof(struct br_port_msg))
                + nla_total_size(sizeof(__u32))
                + nla_total_size(sizeof(u16));
}

void br_rtr_notify(struct net_device *dev, struct net_bridge_mcast_port *pmctx,
                   int type)
{
        struct net *net = dev_net(dev);
        struct sk_buff *skb;
        int err = -ENOBUFS;
        int ifindex;
        u16 vid;

        ifindex = pmctx ? pmctx->port->dev->ifindex : 0;
        vid = pmctx && br_multicast_port_ctx_is_vlan(pmctx) ? pmctx->vlan->vid :
                                                              0;
        skb = nlmsg_new(rtnl_rtr_nlmsg_size(), GFP_ATOMIC);
        if (!skb)
                goto errout;

        err = nlmsg_populate_rtr_fill(skb, dev, ifindex, vid, 0, 0, type,
                                      NTF_SELF);
        if (err < 0) {
                kfree_skb(skb);
                goto errout;
        }

        rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC);
        return;

errout:
        rtnl_set_sk_err(net, RTNLGRP_MDB, err);
}

static const struct nla_policy
br_mdbe_src_list_entry_pol[MDBE_SRCATTR_MAX + 1] = {
        [MDBE_SRCATTR_ADDRESS] = NLA_POLICY_RANGE(NLA_BINARY,
                                                  sizeof(struct in_addr),
                                                  sizeof(struct in6_addr)),
};

static const struct nla_policy
br_mdbe_src_list_pol[MDBE_SRC_LIST_MAX + 1] = {
        [MDBE_SRC_LIST_ENTRY] = NLA_POLICY_NESTED(br_mdbe_src_list_entry_pol),
};

static const struct nla_policy br_mdbe_attrs_pol[MDBE_ATTR_MAX + 1] = {
        [MDBE_ATTR_SOURCE] = NLA_POLICY_RANGE(NLA_BINARY,
                                              sizeof(struct in_addr),
                                              sizeof(struct in6_addr)),
        [MDBE_ATTR_GROUP_MODE] = NLA_POLICY_RANGE(NLA_U8, MCAST_EXCLUDE,
                                                  MCAST_INCLUDE),
        [MDBE_ATTR_SRC_LIST] = NLA_POLICY_NESTED(br_mdbe_src_list_pol),
        [MDBE_ATTR_RTPROT] = NLA_POLICY_MIN(NLA_U8, RTPROT_STATIC),
};

static bool is_valid_mdb_source(struct nlattr *attr, __be16 proto,
                                struct netlink_ext_ack *extack)
{
        switch (proto) {
        case htons(ETH_P_IP):
                if (nla_len(attr) != sizeof(struct in_addr)) {
                        NL_SET_ERR_MSG_MOD(extack, "IPv4 invalid source address length");
                        return false;
                }
                if (ipv4_is_multicast(nla_get_in_addr(attr))) {
                        NL_SET_ERR_MSG_MOD(extack, "IPv4 multicast source address is not allowed");
                        return false;
                }
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case htons(ETH_P_IPV6): {
                struct in6_addr src;

                if (nla_len(attr) != sizeof(struct in6_addr)) {
                        NL_SET_ERR_MSG_MOD(extack, "IPv6 invalid source address length");
                        return false;
                }
                src = nla_get_in6_addr(attr);
                if (ipv6_addr_is_multicast(&src)) {
                        NL_SET_ERR_MSG_MOD(extack, "IPv6 multicast source address is not allowed");
                        return false;
                }
                break;
        }
#endif
        default:
                NL_SET_ERR_MSG_MOD(extack, "Invalid protocol used with source address");
                return false;
        }

        return true;
}

static struct net_bridge_mcast *
__br_mdb_choose_context(struct net_bridge *br,
                        const struct br_mdb_entry *entry,
                        struct netlink_ext_ack *extack)
{
        struct net_bridge_mcast *brmctx = NULL;
        struct net_bridge_vlan *v;

        if (!br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED)) {
                brmctx = &br->multicast_ctx;
                goto out;
        }

        if (!entry->vid) {
                NL_SET_ERR_MSG_MOD(extack, "Cannot add an entry without a vlan when vlan snooping is enabled");
                goto out;
        }

        v = br_vlan_find(br_vlan_group(br), entry->vid);
        if (!v) {
                NL_SET_ERR_MSG_MOD(extack, "Vlan is not configured");
                goto out;
        }
        if (br_multicast_ctx_vlan_global_disabled(&v->br_mcast_ctx)) {
                NL_SET_ERR_MSG_MOD(extack, "Vlan's multicast processing is disabled");
                goto out;
        }
        brmctx = &v->br_mcast_ctx;
out:
        return brmctx;
}

static int br_mdb_replace_group_sg(const struct br_mdb_config *cfg,
                                   struct net_bridge_mdb_entry *mp,
                                   struct net_bridge_port_group *pg,
                                   struct net_bridge_mcast *brmctx,
                                   unsigned char flags)
{
        unsigned long now = jiffies;

        pg->flags = flags;
        pg->rt_protocol = cfg->rt_protocol;
        if (!(flags & MDB_PG_FLAGS_PERMANENT) && !cfg->src_entry)
                mod_timer(&pg->timer,
                          now + brmctx->multicast_membership_interval);
        else
                timer_delete(&pg->timer);

        br_mdb_notify(cfg->br->dev, mp, pg, RTM_NEWMDB);

        return 0;
}

static int br_mdb_add_group_sg(const struct br_mdb_config *cfg,
                               struct net_bridge_mdb_entry *mp,
                               struct net_bridge_mcast *brmctx,
                               unsigned char flags,
                               struct netlink_ext_ack *extack)
{
        struct net_bridge_port_group __rcu **pp;
        struct net_bridge_port_group *p;
        unsigned long now = jiffies;

        for (pp = &mp->ports;
             (p = mlock_dereference(*pp, cfg->br)) != NULL;
             pp = &p->next) {
                if (p->key.port == cfg->p) {
                        if (!(cfg->nlflags & NLM_F_REPLACE)) {
                                NL_SET_ERR_MSG_MOD(extack, "(S, G) group is already joined by port");
                                return -EEXIST;
                        }
                        return br_mdb_replace_group_sg(cfg, mp, p, brmctx,
                                                       flags);
                }
                if ((unsigned long)p->key.port < (unsigned long)cfg->p)
                        break;
        }

        p = br_multicast_new_port_group(cfg->p, &cfg->group, *pp, flags, NULL,
                                        MCAST_INCLUDE, cfg->rt_protocol, extack);
        if (unlikely(!p))
                return -ENOMEM;

        rcu_assign_pointer(*pp, p);
        if (!(flags & MDB_PG_FLAGS_PERMANENT) && !cfg->src_entry)
                mod_timer(&p->timer,
                          now + brmctx->multicast_membership_interval);
        br_mdb_notify(cfg->br->dev, mp, p, RTM_NEWMDB);

        /* All of (*, G) EXCLUDE ports need to be added to the new (S, G) for
         * proper replication.
         */
        if (br_multicast_should_handle_mode(brmctx, cfg->group.proto)) {
                struct net_bridge_mdb_entry *star_mp;
                struct br_ip star_group;

                star_group = p->key.addr;
                memset(&star_group.src, 0, sizeof(star_group.src));
                star_mp = br_mdb_ip_get(cfg->br, &star_group);
                if (star_mp)
                        br_multicast_sg_add_exclude_ports(star_mp, p);
        }

        return 0;
}

static int br_mdb_add_group_src_fwd(const struct br_mdb_config *cfg,
                                    struct br_ip *src_ip,
                                    struct net_bridge_mcast *brmctx,
                                    struct netlink_ext_ack *extack)
{
        struct net_bridge_mdb_entry *sgmp;
        struct br_mdb_config sg_cfg;
        struct br_ip sg_ip;
        u8 flags = 0;

        sg_ip = cfg->group;
        sg_ip.src = src_ip->src;
        sgmp = br_multicast_new_group(cfg->br, &sg_ip);
        if (IS_ERR(sgmp)) {
                NL_SET_ERR_MSG_MOD(extack, "Failed to add (S, G) MDB entry");
                return PTR_ERR(sgmp);
        }

        if (cfg->entry->state == MDB_PERMANENT)
                flags |= MDB_PG_FLAGS_PERMANENT;
        if (cfg->filter_mode == MCAST_EXCLUDE)
                flags |= MDB_PG_FLAGS_BLOCKED;

        memset(&sg_cfg, 0, sizeof(sg_cfg));
        sg_cfg.br = cfg->br;
        sg_cfg.p = cfg->p;
        sg_cfg.entry = cfg->entry;
        sg_cfg.group = sg_ip;
        sg_cfg.src_entry = true;
        sg_cfg.filter_mode = MCAST_INCLUDE;
        sg_cfg.rt_protocol = cfg->rt_protocol;
        sg_cfg.nlflags = cfg->nlflags;
        return br_mdb_add_group_sg(&sg_cfg, sgmp, brmctx, flags, extack);
}

static int br_mdb_add_group_src(const struct br_mdb_config *cfg,
                                struct net_bridge_port_group *pg,
                                struct net_bridge_mcast *brmctx,
                                struct br_mdb_src_entry *src,
                                struct netlink_ext_ack *extack)
{
        struct net_bridge_group_src *ent;
        unsigned long now = jiffies;
        int err;

        ent = br_multicast_find_group_src(pg, &src->addr);
        if (!ent) {
                ent = br_multicast_new_group_src(pg, &src->addr);
                if (!ent) {
                        NL_SET_ERR_MSG_MOD(extack, "Failed to add new source entry");
                        return -ENOSPC;
                }
        } else if (!(cfg->nlflags & NLM_F_REPLACE)) {
                NL_SET_ERR_MSG_MOD(extack, "Source entry already exists");
                return -EEXIST;
        }

        if (cfg->filter_mode == MCAST_INCLUDE &&
            cfg->entry->state == MDB_TEMPORARY)
                mod_timer(&ent->timer, now + br_multicast_gmi(brmctx));
        else
                timer_delete(&ent->timer);

        /* Install a (S, G) forwarding entry for the source. */
        err = br_mdb_add_group_src_fwd(cfg, &src->addr, brmctx, extack);
        if (err)
                goto err_del_sg;

        ent->flags = BR_SGRP_F_INSTALLED | BR_SGRP_F_USER_ADDED;

        return 0;

err_del_sg:
        __br_multicast_del_group_src(ent);
        return err;
}

static void br_mdb_del_group_src(struct net_bridge_port_group *pg,
                                 struct br_mdb_src_entry *src)
{
        struct net_bridge_group_src *ent;

        ent = br_multicast_find_group_src(pg, &src->addr);
        if (WARN_ON_ONCE(!ent))
                return;
        br_multicast_del_group_src(ent, false);
}

static int br_mdb_add_group_srcs(const struct br_mdb_config *cfg,
                                 struct net_bridge_port_group *pg,
                                 struct net_bridge_mcast *brmctx,
                                 struct netlink_ext_ack *extack)
{
        int i, err;

        for (i = 0; i < cfg->num_src_entries; i++) {
                err = br_mdb_add_group_src(cfg, pg, brmctx,
                                           &cfg->src_entries[i], extack);
                if (err)
                        goto err_del_group_srcs;
        }

        return 0;

err_del_group_srcs:
        for (i--; i >= 0; i--)
                br_mdb_del_group_src(pg, &cfg->src_entries[i]);
        return err;
}

static int br_mdb_replace_group_srcs(const struct br_mdb_config *cfg,
                                     struct net_bridge_port_group *pg,
                                     struct net_bridge_mcast *brmctx,
                                     struct netlink_ext_ack *extack)
{
        struct net_bridge_group_src *ent;
        struct hlist_node *tmp;
        int err;

        hlist_for_each_entry(ent, &pg->src_list, node)
                ent->flags |= BR_SGRP_F_DELETE;

        err = br_mdb_add_group_srcs(cfg, pg, brmctx, extack);
        if (err)
                goto err_clear_delete;

        hlist_for_each_entry_safe(ent, tmp, &pg->src_list, node) {
                if (ent->flags & BR_SGRP_F_DELETE)
                        br_multicast_del_group_src(ent, false);
        }

        return 0;

err_clear_delete:
        hlist_for_each_entry(ent, &pg->src_list, node)
                ent->flags &= ~BR_SGRP_F_DELETE;
        return err;
}

static int br_mdb_replace_group_star_g(const struct br_mdb_config *cfg,
                                       struct net_bridge_mdb_entry *mp,
                                       struct net_bridge_port_group *pg,
                                       struct net_bridge_mcast *brmctx,
                                       unsigned char flags,
                                       struct netlink_ext_ack *extack)
{
        unsigned long now = jiffies;
        int err;

        err = br_mdb_replace_group_srcs(cfg, pg, brmctx, extack);
        if (err)
                return err;

        pg->flags = flags;
        pg->filter_mode = cfg->filter_mode;
        pg->rt_protocol = cfg->rt_protocol;
        if (!(flags & MDB_PG_FLAGS_PERMANENT) &&
            cfg->filter_mode == MCAST_EXCLUDE)
                mod_timer(&pg->timer,
                          now + brmctx->multicast_membership_interval);
        else
                timer_delete(&pg->timer);

        br_mdb_notify(cfg->br->dev, mp, pg, RTM_NEWMDB);

        if (br_multicast_should_handle_mode(brmctx, cfg->group.proto))
                br_multicast_star_g_handle_mode(pg, cfg->filter_mode);

        return 0;
}

static int br_mdb_add_group_star_g(const struct br_mdb_config *cfg,
                                   struct net_bridge_mdb_entry *mp,
                                   struct net_bridge_mcast *brmctx,
                                   unsigned char flags,
                                   struct netlink_ext_ack *extack)
{
        struct net_bridge_port_group __rcu **pp;
        struct net_bridge_port_group *p;
        unsigned long now = jiffies;
        int err;

        for (pp = &mp->ports;
             (p = mlock_dereference(*pp, cfg->br)) != NULL;
             pp = &p->next) {
                if (p->key.port == cfg->p) {
                        if (!(cfg->nlflags & NLM_F_REPLACE)) {
                                NL_SET_ERR_MSG_MOD(extack, "(*, G) group is already joined by port");
                                return -EEXIST;
                        }
                        return br_mdb_replace_group_star_g(cfg, mp, p, brmctx,
                                                           flags, extack);
                }
                if ((unsigned long)p->key.port < (unsigned long)cfg->p)
                        break;
        }

        p = br_multicast_new_port_group(cfg->p, &cfg->group, *pp, flags, NULL,
                                        cfg->filter_mode, cfg->rt_protocol,
                                        extack);
        if (unlikely(!p))
                return -ENOMEM;

        err = br_mdb_add_group_srcs(cfg, p, brmctx, extack);
        if (err)
                goto err_del_port_group;

        rcu_assign_pointer(*pp, p);
        if (!(flags & MDB_PG_FLAGS_PERMANENT) &&
            cfg->filter_mode == MCAST_EXCLUDE)
                mod_timer(&p->timer,
                          now + brmctx->multicast_membership_interval);
        br_mdb_notify(cfg->br->dev, mp, p, RTM_NEWMDB);
        /* If we are adding a new EXCLUDE port group (*, G), it needs to be
         * also added to all (S, G) entries for proper replication.
         */
        if (br_multicast_should_handle_mode(brmctx, cfg->group.proto) &&
            cfg->filter_mode == MCAST_EXCLUDE)
                br_multicast_star_g_handle_mode(p, MCAST_EXCLUDE);

        return 0;

err_del_port_group:
        br_multicast_del_port_group(p);
        return err;
}

static int br_mdb_add_group(const struct br_mdb_config *cfg,
                            struct netlink_ext_ack *extack)
{
        struct br_mdb_entry *entry = cfg->entry;
        struct net_bridge_port *port = cfg->p;
        struct net_bridge_mdb_entry *mp;
        struct net_bridge *br = cfg->br;
        struct net_bridge_mcast *brmctx;
        struct br_ip group = cfg->group;
        unsigned char flags = 0;

        brmctx = __br_mdb_choose_context(br, entry, extack);
        if (!brmctx)
                return -EINVAL;

        mp = br_multicast_new_group(br, &group);
        if (IS_ERR(mp))
                return PTR_ERR(mp);

        /* host join */
        if (!port) {
                if (mp->host_joined && !(cfg->nlflags & NLM_F_REPLACE)) {
                        NL_SET_ERR_MSG_MOD(extack, "Group is already joined by host");
                        return -EEXIST;
                }

                br_multicast_host_join(brmctx, mp, false);
                br_mdb_notify(br->dev, mp, NULL, RTM_NEWMDB);

                return 0;
        }

        if (entry->state == MDB_PERMANENT)
                flags |= MDB_PG_FLAGS_PERMANENT;

        if (br_multicast_is_star_g(&group))
                return br_mdb_add_group_star_g(cfg, mp, brmctx, flags, extack);
        else
                return br_mdb_add_group_sg(cfg, mp, brmctx, flags, extack);
}

static int __br_mdb_add(const struct br_mdb_config *cfg,
                        struct netlink_ext_ack *extack)
{
        int ret;

        spin_lock_bh(&cfg->br->multicast_lock);
        ret = br_mdb_add_group(cfg, extack);
        spin_unlock_bh(&cfg->br->multicast_lock);

        return ret;
}

static int br_mdb_config_src_entry_init(struct nlattr *src_entry,
                                        struct br_mdb_src_entry *src,
                                        __be16 proto,
                                        struct netlink_ext_ack *extack)
{
        struct nlattr *tb[MDBE_SRCATTR_MAX + 1];
        int err;

        err = nla_parse_nested(tb, MDBE_SRCATTR_MAX, src_entry,
                               br_mdbe_src_list_entry_pol, extack);
        if (err)
                return err;

        if (NL_REQ_ATTR_CHECK(extack, src_entry, tb, MDBE_SRCATTR_ADDRESS))
                return -EINVAL;

        if (!is_valid_mdb_source(tb[MDBE_SRCATTR_ADDRESS], proto, extack))
                return -EINVAL;

        src->addr.proto = proto;
        nla_memcpy(&src->addr.src, tb[MDBE_SRCATTR_ADDRESS],
                   nla_len(tb[MDBE_SRCATTR_ADDRESS]));

        return 0;
}

static int br_mdb_config_src_list_init(struct nlattr *src_list,
                                       struct br_mdb_config *cfg,
                                       struct netlink_ext_ack *extack)
{
        struct nlattr *src_entry;
        int rem, err;
        int i = 0;

        nla_for_each_nested(src_entry, src_list, rem)
                cfg->num_src_entries++;

        if (cfg->num_src_entries >= PG_SRC_ENT_LIMIT) {
                NL_SET_ERR_MSG_FMT_MOD(extack, "Exceeded maximum number of source entries (%u)",
                                       PG_SRC_ENT_LIMIT - 1);
                return -EINVAL;
        }

        cfg->src_entries = kzalloc_objs(struct br_mdb_src_entry,
                                        cfg->num_src_entries);
        if (!cfg->src_entries)
                return -ENOMEM;

        nla_for_each_nested(src_entry, src_list, rem) {
                err = br_mdb_config_src_entry_init(src_entry,
                                                   &cfg->src_entries[i],
                                                   cfg->entry->addr.proto,
                                                   extack);
                if (err)
                        goto err_src_entry_init;
                i++;
        }

        return 0;

err_src_entry_init:
        kfree(cfg->src_entries);
        return err;
}

static void br_mdb_config_src_list_fini(struct br_mdb_config *cfg)
{
        kfree(cfg->src_entries);
}

static int br_mdb_config_attrs_init(struct nlattr *set_attrs,
                                    struct br_mdb_config *cfg,
                                    struct netlink_ext_ack *extack)
{
        struct nlattr *mdb_attrs[MDBE_ATTR_MAX + 1];
        int err;

        err = nla_parse_nested(mdb_attrs, MDBE_ATTR_MAX, set_attrs,
                               br_mdbe_attrs_pol, extack);
        if (err)
                return err;

        if (mdb_attrs[MDBE_ATTR_SOURCE] &&
            !is_valid_mdb_source(mdb_attrs[MDBE_ATTR_SOURCE],
                                 cfg->entry->addr.proto, extack))
                return -EINVAL;

        __mdb_entry_to_br_ip(cfg->entry, &cfg->group, mdb_attrs);

        if (mdb_attrs[MDBE_ATTR_GROUP_MODE]) {
                if (!cfg->p) {
                        NL_SET_ERR_MSG_MOD(extack, "Filter mode cannot be set for host groups");
                        return -EINVAL;
                }
                if (!br_multicast_is_star_g(&cfg->group)) {
                        NL_SET_ERR_MSG_MOD(extack, "Filter mode can only be set for (*, G) entries");
                        return -EINVAL;
                }
                cfg->filter_mode = nla_get_u8(mdb_attrs[MDBE_ATTR_GROUP_MODE]);
        } else {
                cfg->filter_mode = MCAST_EXCLUDE;
        }

        if (mdb_attrs[MDBE_ATTR_SRC_LIST]) {
                if (!cfg->p) {
                        NL_SET_ERR_MSG_MOD(extack, "Source list cannot be set for host groups");
                        return -EINVAL;
                }
                if (!br_multicast_is_star_g(&cfg->group)) {
                        NL_SET_ERR_MSG_MOD(extack, "Source list can only be set for (*, G) entries");
                        return -EINVAL;
                }
                if (!mdb_attrs[MDBE_ATTR_GROUP_MODE]) {
                        NL_SET_ERR_MSG_MOD(extack, "Source list cannot be set without filter mode");
                        return -EINVAL;
                }
                err = br_mdb_config_src_list_init(mdb_attrs[MDBE_ATTR_SRC_LIST],
                                                  cfg, extack);
                if (err)
                        return err;
        }

        if (!cfg->num_src_entries && cfg->filter_mode == MCAST_INCLUDE) {
                NL_SET_ERR_MSG_MOD(extack, "Cannot add (*, G) INCLUDE with an empty source list");
                return -EINVAL;
        }

        if (mdb_attrs[MDBE_ATTR_RTPROT]) {
                if (!cfg->p) {
                        NL_SET_ERR_MSG_MOD(extack, "Protocol cannot be set for host groups");
                        return -EINVAL;
                }
                cfg->rt_protocol = nla_get_u8(mdb_attrs[MDBE_ATTR_RTPROT]);
        }

        return 0;
}

static int br_mdb_config_init(struct br_mdb_config *cfg, struct net_device *dev,
                              struct nlattr *tb[], u16 nlmsg_flags,
                              struct netlink_ext_ack *extack)
{
        struct net *net = dev_net(dev);

        memset(cfg, 0, sizeof(*cfg));
        cfg->filter_mode = MCAST_EXCLUDE;
        cfg->rt_protocol = RTPROT_STATIC;
        cfg->nlflags = nlmsg_flags;

        cfg->br = netdev_priv(dev);

        if (!netif_running(cfg->br->dev)) {
                NL_SET_ERR_MSG_MOD(extack, "Bridge device is not running");
                return -EINVAL;
        }

        if (!br_opt_get(cfg->br, BROPT_MULTICAST_ENABLED)) {
                NL_SET_ERR_MSG_MOD(extack, "Bridge's multicast processing is disabled");
                return -EINVAL;
        }

        cfg->entry = nla_data(tb[MDBA_SET_ENTRY]);

        if (cfg->entry->ifindex != cfg->br->dev->ifindex) {
                struct net_device *pdev;

                pdev = __dev_get_by_index(net, cfg->entry->ifindex);
                if (!pdev) {
                        NL_SET_ERR_MSG_MOD(extack, "Port net device doesn't exist");
                        return -ENODEV;
                }

                cfg->p = br_port_get_rtnl(pdev);
                if (!cfg->p) {
                        NL_SET_ERR_MSG_MOD(extack, "Net device is not a bridge port");
                        return -EINVAL;
                }

                if (cfg->p->br != cfg->br) {
                        NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
                        return -EINVAL;
                }
        }

        if (cfg->entry->addr.proto == htons(ETH_P_IP) &&
            ipv4_is_zeronet(cfg->entry->addr.u.ip4)) {
                NL_SET_ERR_MSG_MOD(extack, "IPv4 entry group address 0.0.0.0 is not allowed");
                return -EINVAL;
        }

        if (tb[MDBA_SET_ENTRY_ATTRS])
                return br_mdb_config_attrs_init(tb[MDBA_SET_ENTRY_ATTRS], cfg,
                                                extack);
        else
                __mdb_entry_to_br_ip(cfg->entry, &cfg->group, NULL);

        return 0;
}

static void br_mdb_config_fini(struct br_mdb_config *cfg)
{
        br_mdb_config_src_list_fini(cfg);
}

int br_mdb_add(struct net_device *dev, struct nlattr *tb[], u16 nlmsg_flags,
               struct netlink_ext_ack *extack)
{
        struct net_bridge_vlan_group *vg;
        struct net_bridge_vlan *v;
        struct br_mdb_config cfg;
        int err;

        err = br_mdb_config_init(&cfg, dev, tb, nlmsg_flags, extack);
        if (err)
                return err;

        err = -EINVAL;
        /* host join errors which can happen before creating the group */
        if (!cfg.p && !br_group_is_l2(&cfg.group)) {
                /* don't allow any flags for host-joined IP groups */
                if (cfg.entry->state) {
                        NL_SET_ERR_MSG_MOD(extack, "Flags are not allowed for host groups");
                        goto out;
                }
                if (!br_multicast_is_star_g(&cfg.group)) {
                        NL_SET_ERR_MSG_MOD(extack, "Groups with sources cannot be manually host joined");
                        goto out;
                }
        }

        if (br_group_is_l2(&cfg.group) && cfg.entry->state != MDB_PERMANENT) {
                NL_SET_ERR_MSG_MOD(extack, "Only permanent L2 entries allowed");
                goto out;
        }

        if (cfg.p) {
                if (cfg.p->state == BR_STATE_DISABLED && cfg.entry->state != MDB_PERMANENT) {
                        NL_SET_ERR_MSG_MOD(extack, "Port is in disabled state and entry is not permanent");
                        goto out;
                }
                vg = nbp_vlan_group(cfg.p);
        } else {
                vg = br_vlan_group(cfg.br);
        }

        /* If vlan filtering is enabled and VLAN is not specified
         * install mdb entry on all vlans configured on the port.
         */
        if (br_vlan_enabled(cfg.br->dev) && vg && cfg.entry->vid == 0) {
                list_for_each_entry(v, &vg->vlan_list, vlist) {
                        cfg.entry->vid = v->vid;
                        cfg.group.vid = v->vid;
                        err = __br_mdb_add(&cfg, extack);
                        if (err)
                                break;
                }
        } else {
                err = __br_mdb_add(&cfg, extack);
        }

out:
        br_mdb_config_fini(&cfg);
        return err;
}

static int __br_mdb_del(const struct br_mdb_config *cfg)
{
        struct br_mdb_entry *entry = cfg->entry;
        struct net_bridge *br = cfg->br;
        struct net_bridge_mdb_entry *mp;
        struct net_bridge_port_group *p;
        struct net_bridge_port_group __rcu **pp;
        struct br_ip ip = cfg->group;
        int err = -EINVAL;

        spin_lock_bh(&br->multicast_lock);
        mp = br_mdb_ip_get(br, &ip);
        if (!mp)
                goto unlock;

        /* host leave */
        if (entry->ifindex == mp->br->dev->ifindex && mp->host_joined) {
                br_multicast_host_leave(mp, false);
                err = 0;
                br_mdb_notify(br->dev, mp, NULL, RTM_DELMDB);
                if (!mp->ports && netif_running(br->dev))
                        mod_timer(&mp->timer, jiffies);
                goto unlock;
        }

        for (pp = &mp->ports;
             (p = mlock_dereference(*pp, br)) != NULL;
             pp = &p->next) {
                if (!p->key.port || p->key.port->dev->ifindex != entry->ifindex)
                        continue;

                br_multicast_del_pg(mp, p, pp);
                err = 0;
                break;
        }

unlock:
        spin_unlock_bh(&br->multicast_lock);
        return err;
}

int br_mdb_del(struct net_device *dev, struct nlattr *tb[],
               struct netlink_ext_ack *extack)
{
        struct net_bridge_vlan_group *vg;
        struct net_bridge_vlan *v;
        struct br_mdb_config cfg;
        int err;

        err = br_mdb_config_init(&cfg, dev, tb, 0, extack);
        if (err)
                return err;

        if (cfg.p)
                vg = nbp_vlan_group(cfg.p);
        else
                vg = br_vlan_group(cfg.br);

        /* If vlan filtering is enabled and VLAN is not specified
         * delete mdb entry on all vlans configured on the port.
         */
        if (br_vlan_enabled(cfg.br->dev) && vg && cfg.entry->vid == 0) {
                list_for_each_entry(v, &vg->vlan_list, vlist) {
                        cfg.entry->vid = v->vid;
                        cfg.group.vid = v->vid;
                        err = __br_mdb_del(&cfg);
                }
        } else {
                err = __br_mdb_del(&cfg);
        }

        br_mdb_config_fini(&cfg);
        return err;
}

struct br_mdb_flush_desc {
        u32 port_ifindex;
        u16 vid;
        u8 rt_protocol;
        u8 state;
        u8 state_mask;
};

static const struct nla_policy br_mdbe_attrs_del_bulk_pol[MDBE_ATTR_MAX + 1] = {
        [MDBE_ATTR_RTPROT] = NLA_POLICY_MIN(NLA_U8, RTPROT_STATIC),
        [MDBE_ATTR_STATE_MASK] = NLA_POLICY_MASK(NLA_U8, MDB_PERMANENT),
};

static int br_mdb_flush_desc_init(struct br_mdb_flush_desc *desc,
                                  struct nlattr *tb[],
                                  struct netlink_ext_ack *extack)
{
        struct br_mdb_entry *entry = nla_data(tb[MDBA_SET_ENTRY]);
        struct nlattr *mdbe_attrs[MDBE_ATTR_MAX + 1];
        int err;

        desc->port_ifindex = entry->ifindex;
        desc->vid = entry->vid;
        desc->state = entry->state;

        if (!tb[MDBA_SET_ENTRY_ATTRS])
                return 0;

        err = nla_parse_nested(mdbe_attrs, MDBE_ATTR_MAX,
                               tb[MDBA_SET_ENTRY_ATTRS],
                               br_mdbe_attrs_del_bulk_pol, extack);
        if (err)
                return err;

        if (mdbe_attrs[MDBE_ATTR_STATE_MASK])
                desc->state_mask = nla_get_u8(mdbe_attrs[MDBE_ATTR_STATE_MASK]);

        if (mdbe_attrs[MDBE_ATTR_RTPROT])
                desc->rt_protocol = nla_get_u8(mdbe_attrs[MDBE_ATTR_RTPROT]);

        return 0;
}

static void br_mdb_flush_host(struct net_bridge *br,
                              struct net_bridge_mdb_entry *mp,
                              const struct br_mdb_flush_desc *desc)
{
        u8 state;

        if (desc->port_ifindex && desc->port_ifindex != br->dev->ifindex)
                return;

        if (desc->rt_protocol)
                return;

        state = br_group_is_l2(&mp->addr) ? MDB_PERMANENT : 0;
        if (desc->state_mask && (state & desc->state_mask) != desc->state)
                return;

        br_multicast_host_leave(mp, true);
        if (!mp->ports && netif_running(br->dev))
                mod_timer(&mp->timer, jiffies);
}

static void br_mdb_flush_pgs(struct net_bridge *br,
                             struct net_bridge_mdb_entry *mp,
                             const struct br_mdb_flush_desc *desc)
{
        struct net_bridge_port_group __rcu **pp;
        struct net_bridge_port_group *p;

        for (pp = &mp->ports; (p = mlock_dereference(*pp, br)) != NULL;) {
                u8 state;

                if (desc->port_ifindex &&
                    desc->port_ifindex != p->key.port->dev->ifindex) {
                        pp = &p->next;
                        continue;
                }

                if (desc->rt_protocol && desc->rt_protocol != p->rt_protocol) {
                        pp = &p->next;
                        continue;
                }

                state = p->flags & MDB_PG_FLAGS_PERMANENT ? MDB_PERMANENT : 0;
                if (desc->state_mask &&
                    (state & desc->state_mask) != desc->state) {
                        pp = &p->next;
                        continue;
                }

                br_multicast_del_pg(mp, p, pp);
        }
}

static void br_mdb_flush(struct net_bridge *br,
                         const struct br_mdb_flush_desc *desc)
{
        struct net_bridge_mdb_entry *mp;

        spin_lock_bh(&br->multicast_lock);

        /* Safe variant is not needed because entries are removed from the list
         * upon group timer expiration or bridge deletion.
         */
        hlist_for_each_entry(mp, &br->mdb_list, mdb_node) {
                if (desc->vid && desc->vid != mp->addr.vid)
                        continue;

                br_mdb_flush_host(br, mp, desc);
                br_mdb_flush_pgs(br, mp, desc);
        }

        spin_unlock_bh(&br->multicast_lock);
}

int br_mdb_del_bulk(struct net_device *dev, struct nlattr *tb[],
                    struct netlink_ext_ack *extack)
{
        struct net_bridge *br = netdev_priv(dev);
        struct br_mdb_flush_desc desc = {};
        int err;

        err = br_mdb_flush_desc_init(&desc, tb, extack);
        if (err)
                return err;

        br_mdb_flush(br, &desc);

        return 0;
}

static const struct nla_policy br_mdbe_attrs_get_pol[MDBE_ATTR_MAX + 1] = {
        [MDBE_ATTR_SOURCE] = NLA_POLICY_RANGE(NLA_BINARY,
                                              sizeof(struct in_addr),
                                              sizeof(struct in6_addr)),
};

static int br_mdb_get_parse(struct net_device *dev, struct nlattr *tb[],
                            struct br_ip *group, struct netlink_ext_ack *extack)
{
        struct br_mdb_entry *entry = nla_data(tb[MDBA_GET_ENTRY]);
        struct nlattr *mdbe_attrs[MDBE_ATTR_MAX + 1];
        int err;

        if (!tb[MDBA_GET_ENTRY_ATTRS]) {
                __mdb_entry_to_br_ip(entry, group, NULL);
                return 0;
        }

        err = nla_parse_nested(mdbe_attrs, MDBE_ATTR_MAX,
                               tb[MDBA_GET_ENTRY_ATTRS], br_mdbe_attrs_get_pol,
                               extack);
        if (err)
                return err;

        if (mdbe_attrs[MDBE_ATTR_SOURCE] &&
            !is_valid_mdb_source(mdbe_attrs[MDBE_ATTR_SOURCE],
                                 entry->addr.proto, extack))
                return -EINVAL;

        __mdb_entry_to_br_ip(entry, group, mdbe_attrs);

        return 0;
}

static struct sk_buff *
br_mdb_get_reply_alloc(const struct net_bridge_mdb_entry *mp)
{
        struct net_bridge_port_group *pg;
        size_t nlmsg_size;

        nlmsg_size = NLMSG_ALIGN(sizeof(struct br_port_msg)) +
                     /* MDBA_MDB */
                     nla_total_size(0) +
                     /* MDBA_MDB_ENTRY */
                     nla_total_size(0);

        if (mp->host_joined)
                nlmsg_size += rtnl_mdb_nlmsg_pg_size(NULL);

        for (pg = mlock_dereference(mp->ports, mp->br); pg;
             pg = mlock_dereference(pg->next, mp->br))
                nlmsg_size += rtnl_mdb_nlmsg_pg_size(pg);

        return nlmsg_new(nlmsg_size, GFP_ATOMIC);
}

static int br_mdb_get_reply_fill(struct sk_buff *skb,
                                 struct net_bridge_mdb_entry *mp, u32 portid,
                                 u32 seq)
{
        struct nlattr *mdb_nest, *mdb_entry_nest;
        struct net_bridge_port_group *pg;
        struct br_port_msg *bpm;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, portid, seq, RTM_NEWMDB, sizeof(*bpm), 0);
        if (!nlh)
                return -EMSGSIZE;

        bpm = nlmsg_data(nlh);
        memset(bpm, 0, sizeof(*bpm));
        bpm->family  = AF_BRIDGE;
        bpm->ifindex = mp->br->dev->ifindex;
        mdb_nest = nla_nest_start_noflag(skb, MDBA_MDB);
        if (!mdb_nest) {
                err = -EMSGSIZE;
                goto cancel;
        }
        mdb_entry_nest = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
        if (!mdb_entry_nest) {
                err = -EMSGSIZE;
                goto cancel;
        }

        if (mp->host_joined) {
                err = __mdb_fill_info(skb, mp, NULL);
                if (err)
                        goto cancel;
        }

        for (pg = mlock_dereference(mp->ports, mp->br); pg;
             pg = mlock_dereference(pg->next, mp->br)) {
                err = __mdb_fill_info(skb, mp, pg);
                if (err)
                        goto cancel;
        }

        nla_nest_end(skb, mdb_entry_nest);
        nla_nest_end(skb, mdb_nest);
        nlmsg_end(skb, nlh);

        return 0;

cancel:
        nlmsg_cancel(skb, nlh);
        return err;
}

int br_mdb_get(struct net_device *dev, struct nlattr *tb[], u32 portid, u32 seq,
               struct netlink_ext_ack *extack)
{
        struct net_bridge *br = netdev_priv(dev);
        struct net_bridge_mdb_entry *mp;
        struct sk_buff *skb;
        struct br_ip group;
        int err;

        err = br_mdb_get_parse(dev, tb, &group, extack);
        if (err)
                return err;

        /* Hold the multicast lock to ensure that the MDB entry does not change
         * between the time the reply size is determined and when the reply is
         * filled in.
         */
        spin_lock_bh(&br->multicast_lock);

        mp = br_mdb_ip_get(br, &group);
        if (!mp || (!mp->ports && !mp->host_joined)) {
                NL_SET_ERR_MSG_MOD(extack, "MDB entry not found");
                err = -ENOENT;
                goto unlock;
        }

        skb = br_mdb_get_reply_alloc(mp);
        if (!skb) {
                err = -ENOMEM;
                goto unlock;
        }

        err = br_mdb_get_reply_fill(skb, mp, portid, seq);
        if (err) {
                NL_SET_ERR_MSG_MOD(extack, "Failed to fill MDB get reply");
                goto free;
        }

        spin_unlock_bh(&br->multicast_lock);

        return rtnl_unicast(skb, dev_net(dev), portid);

free:
        kfree_skb(skb);
unlock:
        spin_unlock_bh(&br->multicast_lock);
        return err;
}