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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (C) B.A.T.M.A.N. contributors:
  *
  * Linus Lüssing
  */
 
 #include "multicast.h"
 #include "main.h"
 
 #include <linux/atomic.h>
 #include <linux/bitops.h>
 #include <linux/bug.h>
 #include <linux/byteorder/generic.h>
 #include <linux/container_of.h>
 #include <linux/errno.h>
 #include <linux/etherdevice.h>
 #include <linux/gfp.h>
 #include <linux/icmpv6.h>
 #include <linux/if_bridge.h>
 #include <linux/if_ether.h>
 #include <linux/igmp.h>
 #include <linux/in.h>
 #include <linux/in6.h>
 #include <linux/inetdevice.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/kref.h>
 #include <linux/list.h>
 #include <linux/lockdep.h>
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <linux/printk.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/stddef.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/workqueue.h>
 #include <net/addrconf.h>
 #include <net/genetlink.h>
 #include <net/if_inet6.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
 #include <net/netlink.h>
 #include <net/sock.h>
 #include <uapi/linux/batadv_packet.h>
 #include <uapi/linux/batman_adv.h>
 
 #include "bridge_loop_avoidance.h"
 #include "hard-interface.h"
 #include "hash.h"
 #include "log.h"
 #include "netlink.h"
 #include "send.h"
 #include "soft-interface.h"
 #include "translation-table.h"
 #include "tvlv.h"
 
 static void batadv_mcast_mla_update(struct work_struct *work);
 
 /**
  * batadv_mcast_start_timer() - schedule the multicast periodic worker
  * @bat_priv: the bat priv with all the soft interface information
  */
 static void batadv_mcast_start_timer(struct batadv_priv *bat_priv)
 {
     queue_delayed_work(batadv_event_workqueue, &bat_priv->mcast.work,
                msecs_to_jiffies(BATADV_MCAST_WORK_PERIOD));
 }
 
 /**
  * batadv_mcast_get_bridge() - get the bridge on top of the softif if it exists
  * @soft_iface: netdev struct of the mesh interface
  *
  * If the given soft interface has a bridge on top then the refcount
  * of the according net device is increased.
  *
  * Return: NULL if no such bridge exists. Otherwise the net device of the
  * bridge.
  */
 static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
 {
     struct net_device *upper = soft_iface;
 
     rcu_read_lock();
     do {
         upper = netdev_master_upper_dev_get_rcu(upper);
     } while (upper && !netif_is_bridge_master(upper));
 
     dev_hold(upper);
     rcu_read_unlock();
 
     return upper;
 }
 
 /**
  * batadv_mcast_mla_rtr_flags_softif_get_ipv4() - get mcast router flags from
  *  node for IPv4
  * @dev: the interface to check
  *
  * Checks the presence of an IPv4 multicast router on this node.
  *
  * Caller needs to hold rcu read lock.
  *
  * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR4 otherwise.
  */
 static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv4(struct net_device *dev)
 {
     struct in_device *in_dev = __in_dev_get_rcu(dev);
 
     if (in_dev && IN_DEV_MFORWARD(in_dev))
         return BATADV_NO_FLAGS;
     else
         return BATADV_MCAST_WANT_NO_RTR4;
 }
 
 /**
  * batadv_mcast_mla_rtr_flags_softif_get_ipv6() - get mcast router flags from
  *  node for IPv6
  * @dev: the interface to check
  *
  * Checks the presence of an IPv6 multicast router on this node.
  *
  * Caller needs to hold rcu read lock.
  *
  * Return: BATADV_NO_FLAGS if present, BATADV_MCAST_WANT_NO_RTR6 otherwise.
  */
 #if IS_ENABLED(CONFIG_IPV6_MROUTE)
 static u8 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
 {
     struct inet6_dev *in6_dev = __in6_dev_get(dev);
 
     if (in6_dev && atomic_read(&in6_dev->cnf.mc_forwarding))
         return BATADV_NO_FLAGS;
     else
         return BATADV_MCAST_WANT_NO_RTR6;
 }
 #else
 static inline u8
 batadv_mcast_mla_rtr_flags_softif_get_ipv6(struct net_device *dev)
 {
     return BATADV_MCAST_WANT_NO_RTR6;
 }
 #endif
 
 /**
  * batadv_mcast_mla_rtr_flags_softif_get() - get mcast router flags from node
  * @bat_priv: the bat priv with all the soft interface information
  * @bridge: bridge interface on top of the soft_iface if present,
  *  otherwise pass NULL
  *
  * Checks the presence of IPv4 and IPv6 multicast routers on this
  * node.
  *
  * Return:
  *  BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
  *  BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
  *  BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
  *  The former two OR'd: no multicast router is present
  */
 static u8 batadv_mcast_mla_rtr_flags_softif_get(struct batadv_priv *bat_priv,
                         struct net_device *bridge)
 {
     struct net_device *dev = bridge ? bridge : bat_priv->soft_iface;
     u8 flags = BATADV_NO_FLAGS;
 
     rcu_read_lock();
 
     flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv4(dev);
     flags |= batadv_mcast_mla_rtr_flags_softif_get_ipv6(dev);
 
     rcu_read_unlock();
 
     return flags;
 }
 
 /**
  * batadv_mcast_mla_rtr_flags_bridge_get() - get mcast router flags from bridge
  * @bat_priv: the bat priv with all the soft interface information
  * @bridge: bridge interface on top of the soft_iface if present,
  *  otherwise pass NULL
  *
  * Checks the presence of IPv4 and IPv6 multicast routers behind a bridge.
  *
  * Return:
  *  BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
  *  BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
  *  BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
  *  The former two OR'd: no multicast router is present
  */
 static u8 batadv_mcast_mla_rtr_flags_bridge_get(struct batadv_priv *bat_priv,
                         struct net_device *bridge)
 {
     struct net_device *dev = bat_priv->soft_iface;
     u8 flags = BATADV_NO_FLAGS;
 
     if (!bridge)
         return BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
 
     if (!br_multicast_has_router_adjacent(dev, ETH_P_IP))
         flags |= BATADV_MCAST_WANT_NO_RTR4;
     if (!br_multicast_has_router_adjacent(dev, ETH_P_IPV6))
         flags |= BATADV_MCAST_WANT_NO_RTR6;
 
     return flags;
 }
 
 /**
  * batadv_mcast_mla_rtr_flags_get() - get multicast router flags
  * @bat_priv: the bat priv with all the soft interface information
  * @bridge: bridge interface on top of the soft_iface if present,
  *  otherwise pass NULL
  *
  * Checks the presence of IPv4 and IPv6 multicast routers on this
  * node or behind its bridge.
  *
  * Return:
  *  BATADV_NO_FLAGS: Both an IPv4 and IPv6 multicast router is present
  *  BATADV_MCAST_WANT_NO_RTR4: No IPv4 multicast router is present
  *  BATADV_MCAST_WANT_NO_RTR6: No IPv6 multicast router is present
  *  The former two OR'd: no multicast router is present
  */
 static u8 batadv_mcast_mla_rtr_flags_get(struct batadv_priv *bat_priv,
                      struct net_device *bridge)
 {
     u8 flags = BATADV_MCAST_WANT_NO_RTR4 | BATADV_MCAST_WANT_NO_RTR6;
 
     flags &= batadv_mcast_mla_rtr_flags_softif_get(bat_priv, bridge);
     flags &= batadv_mcast_mla_rtr_flags_bridge_get(bat_priv, bridge);
 
     return flags;
 }
 
 /**
  * batadv_mcast_mla_flags_get() - get the new multicast flags
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: A set of flags for the current/next TVLV, querier and
  * bridge state.
  */
 static struct batadv_mcast_mla_flags
 batadv_mcast_mla_flags_get(struct batadv_priv *bat_priv)
 {
     struct net_device *dev = bat_priv->soft_iface;
     struct batadv_mcast_querier_state *qr4, *qr6;
     struct batadv_mcast_mla_flags mla_flags;
     struct net_device *bridge;
 
     bridge = batadv_mcast_get_bridge(dev);
 
     memset(&mla_flags, 0, sizeof(mla_flags));
     mla_flags.enabled = 1;
     mla_flags.tvlv_flags |= batadv_mcast_mla_rtr_flags_get(bat_priv,
                                    bridge);
 
     if (!bridge)
         return mla_flags;
 
     dev_put(bridge);
 
     mla_flags.bridged = 1;
     qr4 = &mla_flags.querier_ipv4;
     qr6 = &mla_flags.querier_ipv6;
 
     if (!IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING))
         pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n");
 
     qr4->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP);
     qr4->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP);
 
     qr6->exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6);
     qr6->shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6);
 
     mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;
 
     /* 1) If no querier exists at all, then multicast listeners on
      *    our local TT clients behind the bridge will keep silent.
      * 2) If the selected querier is on one of our local TT clients,
      *    behind the bridge, then this querier might shadow multicast
      *    listeners on our local TT clients, behind this bridge.
      *
      * In both cases, we will signalize other batman nodes that
      * we need all multicast traffic of the according protocol.
      */
     if (!qr4->exists || qr4->shadowing) {
         mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV4;
         mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR4;
     }
 
     if (!qr6->exists || qr6->shadowing) {
         mla_flags.tvlv_flags |= BATADV_MCAST_WANT_ALL_IPV6;
         mla_flags.tvlv_flags &= ~BATADV_MCAST_WANT_NO_RTR6;
     }
 
     return mla_flags;
 }
 
 /**
  * batadv_mcast_mla_is_duplicate() - check whether an address is in a list
  * @mcast_addr: the multicast address to check
  * @mcast_list: the list with multicast addresses to search in
  *
  * Return: true if the given address is already in the given list.
  * Otherwise returns false.
  */
 static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
                       struct hlist_head *mcast_list)
 {
     struct batadv_hw_addr *mcast_entry;
 
     hlist_for_each_entry(mcast_entry, mcast_list, list)
         if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
             return true;
 
     return false;
 }
 
 /**
  * batadv_mcast_mla_softif_get_ipv4() - get softif IPv4 multicast listeners
  * @dev: the device to collect multicast addresses from
  * @mcast_list: a list to put found addresses into
  * @flags: flags indicating the new multicast state
  *
  * Collects multicast addresses of IPv4 multicast listeners residing
  * on this kernel on the given soft interface, dev, in
  * the given mcast_list. In general, multicast listeners provided by
  * your multicast receiving applications run directly on this node.
  *
  * Return: -ENOMEM on memory allocation error or the number of
  * items added to the mcast_list otherwise.
  */
 static int
 batadv_mcast_mla_softif_get_ipv4(struct net_device *dev,
                  struct hlist_head *mcast_list,
                  struct batadv_mcast_mla_flags *flags)
 {
     struct batadv_hw_addr *new;
     struct in_device *in_dev;
     u8 mcast_addr[ETH_ALEN];
     struct ip_mc_list *pmc;
     int ret = 0;
 
     if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
         return 0;
 
     rcu_read_lock();
 
     in_dev = __in_dev_get_rcu(dev);
     if (!in_dev) {
         rcu_read_unlock();
         return 0;
     }
 
     for (pmc = rcu_dereference(in_dev->mc_list); pmc;
          pmc = rcu_dereference(pmc->next_rcu)) {
         if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
             ipv4_is_local_multicast(pmc->multiaddr))
             continue;
 
         if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
             !ipv4_is_local_multicast(pmc->multiaddr))
             continue;
 
         ip_eth_mc_map(pmc->multiaddr, mcast_addr);
 
         if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
             continue;
 
         new = kmalloc(sizeof(*new), GFP_ATOMIC);
         if (!new) {
             ret = -ENOMEM;
             break;
         }
 
         ether_addr_copy(new->addr, mcast_addr);
         hlist_add_head(&new->list, mcast_list);
         ret++;
     }
     rcu_read_unlock();
 
     return ret;
 }
 
 /**
  * batadv_mcast_mla_softif_get_ipv6() - get softif IPv6 multicast listeners
  * @dev: the device to collect multicast addresses from
  * @mcast_list: a list to put found addresses into
  * @flags: flags indicating the new multicast state
  *
  * Collects multicast addresses of IPv6 multicast listeners residing
  * on this kernel on the given soft interface, dev, in
  * the given mcast_list. In general, multicast listeners provided by
  * your multicast receiving applications run directly on this node.
  *
  * Return: -ENOMEM on memory allocation error or the number of
  * items added to the mcast_list otherwise.
  */
 #if IS_ENABLED(CONFIG_IPV6)
 static int
 batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
                  struct hlist_head *mcast_list,
                  struct batadv_mcast_mla_flags *flags)
 {
     struct batadv_hw_addr *new;
     struct inet6_dev *in6_dev;
     u8 mcast_addr[ETH_ALEN];
     struct ifmcaddr6 *pmc6;
     int ret = 0;
 
     if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
         return 0;
 
     rcu_read_lock();
 
     in6_dev = __in6_dev_get(dev);
     if (!in6_dev) {
         rcu_read_unlock();
         return 0;
     }
 
     for (pmc6 = rcu_dereference(in6_dev->mc_list);
          pmc6;
          pmc6 = rcu_dereference(pmc6->next)) {
         if (IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) <
             IPV6_ADDR_SCOPE_LINKLOCAL)
             continue;
 
         if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
             ipv6_addr_is_ll_all_nodes(&pmc6->mca_addr))
             continue;
 
         if (!(flags->tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
             IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) >
             IPV6_ADDR_SCOPE_LINKLOCAL)
             continue;
 
         ipv6_eth_mc_map(&pmc6->mca_addr, mcast_addr);
 
         if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
             continue;
 
         new = kmalloc(sizeof(*new), GFP_ATOMIC);
         if (!new) {
             ret = -ENOMEM;
             break;
         }
 
         ether_addr_copy(new->addr, mcast_addr);
         hlist_add_head(&new->list, mcast_list);
         ret++;
     }
     rcu_read_unlock();
 
     return ret;
 }
 #else
 static inline int
 batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
                  struct hlist_head *mcast_list,
                  struct batadv_mcast_mla_flags *flags)
 {
     return 0;
 }
 #endif
 
 /**
  * batadv_mcast_mla_softif_get() - get softif multicast listeners
  * @dev: the device to collect multicast addresses from
  * @mcast_list: a list to put found addresses into
  * @flags: flags indicating the new multicast state
  *
  * Collects multicast addresses of multicast listeners residing
  * on this kernel on the given soft interface, dev, in
  * the given mcast_list. In general, multicast listeners provided by
  * your multicast receiving applications run directly on this node.
  *
  * If there is a bridge interface on top of dev, collect from that one
  * instead. Just like with IP addresses and routes, multicast listeners
  * will(/should) register to the bridge interface instead of an
  * enslaved bat0.
  *
  * Return: -ENOMEM on memory allocation error or the number of
  * items added to the mcast_list otherwise.
  */
 static int
 batadv_mcast_mla_softif_get(struct net_device *dev,
                 struct hlist_head *mcast_list,
                 struct batadv_mcast_mla_flags *flags)
 {
     struct net_device *bridge = batadv_mcast_get_bridge(dev);
     int ret4, ret6 = 0;
 
     if (bridge)
         dev = bridge;
 
     ret4 = batadv_mcast_mla_softif_get_ipv4(dev, mcast_list, flags);
     if (ret4 < 0)
         goto out;
 
     ret6 = batadv_mcast_mla_softif_get_ipv6(dev, mcast_list, flags);
     if (ret6 < 0) {
         ret4 = 0;
         goto out;
     }
 
 out:
     dev_put(bridge);
 
     return ret4 + ret6;
 }
 
 /**
  * batadv_mcast_mla_br_addr_cpy() - copy a bridge multicast address
  * @dst: destination to write to - a multicast MAC address
  * @src: source to read from - a multicast IP address
  *
  * Converts a given multicast IPv4/IPv6 address from a bridge
  * to its matching multicast MAC address and copies it into the given
  * destination buffer.
  *
  * Caller needs to make sure the destination buffer can hold
  * at least ETH_ALEN bytes.
  */
 static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
 {
     if (src->proto == htons(ETH_P_IP))
         ip_eth_mc_map(src->dst.ip4, dst);
 #if IS_ENABLED(CONFIG_IPV6)
     else if (src->proto == htons(ETH_P_IPV6))
         ipv6_eth_mc_map(&src->dst.ip6, dst);
 #endif
     else
         eth_zero_addr(dst);
 }
 
 /**
  * batadv_mcast_mla_bridge_get() - get bridged-in multicast listeners
  * @dev: a bridge slave whose bridge to collect multicast addresses from
  * @mcast_list: a list to put found addresses into
  * @flags: flags indicating the new multicast state
  *
  * Collects multicast addresses of multicast listeners residing
  * on foreign, non-mesh devices which we gave access to our mesh via
  * a bridge on top of the given soft interface, dev, in the given
  * mcast_list.
  *
  * Return: -ENOMEM on memory allocation error or the number of
  * items added to the mcast_list otherwise.
  */
 static int batadv_mcast_mla_bridge_get(struct net_device *dev,
                        struct hlist_head *mcast_list,
                        struct batadv_mcast_mla_flags *flags)
 {
     struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
     struct br_ip_list *br_ip_entry, *tmp;
     u8 tvlv_flags = flags->tvlv_flags;
     struct batadv_hw_addr *new;
     u8 mcast_addr[ETH_ALEN];
     int ret;
 
     /* we don't need to detect these devices/listeners, the IGMP/MLD
      * snooping code of the Linux bridge already does that for us
      */
     ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
     if (ret < 0)
         goto out;
 
     list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
         if (br_ip_entry->addr.proto == htons(ETH_P_IP)) {
             if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
                 continue;
 
             if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
                 ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
                 continue;
 
             if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR4) &&
                 !ipv4_is_local_multicast(br_ip_entry->addr.dst.ip4))
                 continue;
         }
 
 #if IS_ENABLED(CONFIG_IPV6)
         if (br_ip_entry->addr.proto == htons(ETH_P_IPV6)) {
             if (tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
                 continue;
 
             if (tvlv_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
                 ipv6_addr_is_ll_all_nodes(&br_ip_entry->addr.dst.ip6))
                 continue;
 
             if (!(tvlv_flags & BATADV_MCAST_WANT_NO_RTR6) &&
                 IPV6_ADDR_MC_SCOPE(&br_ip_entry->addr.dst.ip6) >
                 IPV6_ADDR_SCOPE_LINKLOCAL)
                 continue;
         }
 #endif
 
         batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
         if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
             continue;
 
         new = kmalloc(sizeof(*new), GFP_ATOMIC);
         if (!new) {
             ret = -ENOMEM;
             break;
         }
 
         ether_addr_copy(new->addr, mcast_addr);
         hlist_add_head(&new->list, mcast_list);
     }
 
 out:
     list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
         list_del(&br_ip_entry->list);
         kfree(br_ip_entry);
     }
 
     return ret;
 }
 
 /**
  * batadv_mcast_mla_list_free() - free a list of multicast addresses
  * @mcast_list: the list to free
  *
  * Removes and frees all items in the given mcast_list.
  */
 static void batadv_mcast_mla_list_free(struct hlist_head *mcast_list)
 {
     struct batadv_hw_addr *mcast_entry;
     struct hlist_node *tmp;
 
     hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
         hlist_del(&mcast_entry->list);
         kfree(mcast_entry);
     }
 }
 
 /**
  * batadv_mcast_mla_tt_retract() - clean up multicast listener announcements
  * @bat_priv: the bat priv with all the soft interface information
  * @mcast_list: a list of addresses which should _not_ be removed
  *
  * Retracts the announcement of any multicast listener from the
  * translation table except the ones listed in the given mcast_list.
  *
  * If mcast_list is NULL then all are retracted.
  */
 static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
                     struct hlist_head *mcast_list)
 {
     struct batadv_hw_addr *mcast_entry;
     struct hlist_node *tmp;
 
     hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
                   list) {
         if (mcast_list &&
             batadv_mcast_mla_is_duplicate(mcast_entry->addr,
                           mcast_list))
             continue;
 
         batadv_tt_local_remove(bat_priv, mcast_entry->addr,
                        BATADV_NO_FLAGS,
                        "mcast TT outdated", false);
 
         hlist_del(&mcast_entry->list);
         kfree(mcast_entry);
     }
 }
 
 /**
  * batadv_mcast_mla_tt_add() - add multicast listener announcements
  * @bat_priv: the bat priv with all the soft interface information
  * @mcast_list: a list of addresses which are going to get added
  *
  * Adds multicast listener announcements from the given mcast_list to the
  * translation table if they have not been added yet.
  */
 static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
                     struct hlist_head *mcast_list)
 {
     struct batadv_hw_addr *mcast_entry;
     struct hlist_node *tmp;
 
     if (!mcast_list)
         return;
 
     hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
         if (batadv_mcast_mla_is_duplicate(mcast_entry->addr,
                           &bat_priv->mcast.mla_list))
             continue;
 
         if (!batadv_tt_local_add(bat_priv->soft_iface,
                      mcast_entry->addr, BATADV_NO_FLAGS,
                      BATADV_NULL_IFINDEX, BATADV_NO_MARK))
             continue;
 
         hlist_del(&mcast_entry->list);
         hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list);
     }
 }
 
 /**
  * batadv_mcast_querier_log() - debug output regarding the querier status on
  *  link
  * @bat_priv: the bat priv with all the soft interface information
  * @str_proto: a string for the querier protocol (e.g. "IGMP" or "MLD")
  * @old_state: the previous querier state on our link
  * @new_state: the new querier state on our link
  *
  * Outputs debug messages to the logging facility with log level 'mcast'
  * regarding changes to the querier status on the link which are relevant
  * to our multicast optimizations.
  *
  * Usually this is about whether a querier appeared or vanished in
  * our mesh or whether the querier is in the suboptimal position of being
  * behind our local bridge segment: Snooping switches will directly
  * forward listener reports to the querier, therefore batman-adv and
  * the bridge will potentially not see these listeners - the querier is
  * potentially shadowing listeners from us then.
  *
  * This is only interesting for nodes with a bridge on top of their
  * soft interface.
  */
 static void
 batadv_mcast_querier_log(struct batadv_priv *bat_priv, char *str_proto,
              struct batadv_mcast_querier_state *old_state,
              struct batadv_mcast_querier_state *new_state)
 {
     if (!old_state->exists && new_state->exists)
         batadv_info(bat_priv->soft_iface, "%s Querier appeared\n",
                 str_proto);
     else if (old_state->exists && !new_state->exists)
         batadv_info(bat_priv->soft_iface,
                 "%s Querier disappeared - multicast optimizations disabled\n",
                 str_proto);
     else if (!bat_priv->mcast.mla_flags.bridged && !new_state->exists)
         batadv_info(bat_priv->soft_iface,
                 "No %s Querier present - multicast optimizations disabled\n",
                 str_proto);
 
     if (new_state->exists) {
         if ((!old_state->shadowing && new_state->shadowing) ||
             (!old_state->exists && new_state->shadowing))
             batadv_dbg(BATADV_DBG_MCAST, bat_priv,
                    "%s Querier is behind our bridged segment: Might shadow listeners\n",
                    str_proto);
         else if (old_state->shadowing && !new_state->shadowing)
             batadv_dbg(BATADV_DBG_MCAST, bat_priv,
                    "%s Querier is not behind our bridged segment\n",
                    str_proto);
     }
 }
 
 /**
  * batadv_mcast_bridge_log() - debug output for topology changes in bridged
  *  setups
  * @bat_priv: the bat priv with all the soft interface information
  * @new_flags: flags indicating the new multicast state
  *
  * If no bridges are ever used on this node, then this function does nothing.
  *
  * Otherwise this function outputs debug information to the 'mcast' log level
  * which might be relevant to our multicast optimizations.
  *
  * More precisely, it outputs information when a bridge interface is added or
  * removed from a soft interface. And when a bridge is present, it further
  * outputs information about the querier state which is relevant for the
  * multicast flags this node is going to set.
  */
 static void
 batadv_mcast_bridge_log(struct batadv_priv *bat_priv,
             struct batadv_mcast_mla_flags *new_flags)
 {
     struct batadv_mcast_mla_flags *old_flags = &bat_priv->mcast.mla_flags;
 
     if (!old_flags->bridged && new_flags->bridged)
         batadv_dbg(BATADV_DBG_MCAST, bat_priv,
                "Bridge added: Setting Unsnoopables(U)-flag\n");
     else if (old_flags->bridged && !new_flags->bridged)
         batadv_dbg(BATADV_DBG_MCAST, bat_priv,
                "Bridge removed: Unsetting Unsnoopables(U)-flag\n");
 
     if (new_flags->bridged) {
         batadv_mcast_querier_log(bat_priv, "IGMP",
                      &old_flags->querier_ipv4,
                      &new_flags->querier_ipv4);
         batadv_mcast_querier_log(bat_priv, "MLD",
                      &old_flags->querier_ipv6,
                      &new_flags->querier_ipv6);
     }
 }
 
 /**
  * batadv_mcast_flags_log() - output debug information about mcast flag changes
  * @bat_priv: the bat priv with all the soft interface information
  * @flags: TVLV flags indicating the new multicast state
  *
  * Whenever the multicast TVLV flags this node announces change, this function
  * should be used to notify userspace about the change.
  */
 static void batadv_mcast_flags_log(struct batadv_priv *bat_priv, u8 flags)
 {
     bool old_enabled = bat_priv->mcast.mla_flags.enabled;
     u8 old_flags = bat_priv->mcast.mla_flags.tvlv_flags;
     char str_old_flags[] = "[.... . ]";
 
     sprintf(str_old_flags, "[%c%c%c%s%s]",
         (old_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
         (old_flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
         (old_flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
         !(old_flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
         !(old_flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
 
     batadv_dbg(BATADV_DBG_MCAST, bat_priv,
            "Changing multicast flags from '%s' to '[%c%c%c%s%s]'\n",
            old_enabled ? str_old_flags : "<undefined>",
            (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) ? 'U' : '.',
            (flags & BATADV_MCAST_WANT_ALL_IPV4) ? '4' : '.',
            (flags & BATADV_MCAST_WANT_ALL_IPV6) ? '6' : '.',
            !(flags & BATADV_MCAST_WANT_NO_RTR4) ? "R4" : ". ",
            !(flags & BATADV_MCAST_WANT_NO_RTR6) ? "R6" : ". ");
 }
 
 /**
  * batadv_mcast_mla_flags_update() - update multicast flags
  * @bat_priv: the bat priv with all the soft interface information
  * @flags: flags indicating the new multicast state
  *
  * Updates the own multicast tvlv with our current multicast related settings,
  * capabilities and inabilities.
  */
 static void
 batadv_mcast_mla_flags_update(struct batadv_priv *bat_priv,
                   struct batadv_mcast_mla_flags *flags)
 {
     struct batadv_tvlv_mcast_data mcast_data;
 
     if (!memcmp(flags, &bat_priv->mcast.mla_flags, sizeof(*flags)))
         return;
 
     batadv_mcast_bridge_log(bat_priv, flags);
     batadv_mcast_flags_log(bat_priv, flags->tvlv_flags);
 
     mcast_data.flags = flags->tvlv_flags;
     memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
 
     batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
                        &mcast_data, sizeof(mcast_data));
 
     bat_priv->mcast.mla_flags = *flags;
 }
 
 /**
  * __batadv_mcast_mla_update() - update the own MLAs
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Updates the own multicast listener announcements in the translation
  * table as well as the own, announced multicast tvlv container.
  *
  * Note that non-conflicting reads and writes to bat_priv->mcast.mla_list
  * in batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add() are
  * ensured by the non-parallel execution of the worker this function
  * belongs to.
  */
 static void __batadv_mcast_mla_update(struct batadv_priv *bat_priv)
 {
     struct net_device *soft_iface = bat_priv->soft_iface;
     struct hlist_head mcast_list = HLIST_HEAD_INIT;
     struct batadv_mcast_mla_flags flags;
     int ret;
 
     flags = batadv_mcast_mla_flags_get(bat_priv);
 
     ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list, &flags);
     if (ret < 0)
         goto out;
 
     ret = batadv_mcast_mla_bridge_get(soft_iface, &mcast_list, &flags);
     if (ret < 0)
         goto out;
 
     spin_lock(&bat_priv->mcast.mla_lock);
     batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
     batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
     batadv_mcast_mla_flags_update(bat_priv, &flags);
     spin_unlock(&bat_priv->mcast.mla_lock);
 
 out:
     batadv_mcast_mla_list_free(&mcast_list);
 }
 
 /**
  * batadv_mcast_mla_update() - update the own MLAs
  * @work: kernel work struct
  *
  * Updates the own multicast listener announcements in the translation
  * table as well as the own, announced multicast tvlv container.
  *
  * In the end, reschedules the work timer.
  */
 static void batadv_mcast_mla_update(struct work_struct *work)
 {
     struct delayed_work *delayed_work;
     struct batadv_priv_mcast *priv_mcast;
     struct batadv_priv *bat_priv;
 
     delayed_work = to_delayed_work(work);
     priv_mcast = container_of(delayed_work, struct batadv_priv_mcast, work);
     bat_priv = container_of(priv_mcast, struct batadv_priv, mcast);
 
     __batadv_mcast_mla_update(bat_priv);
     batadv_mcast_start_timer(bat_priv);
 }
 
 /**
  * batadv_mcast_is_report_ipv4() - check for IGMP reports
  * @skb: the ethernet frame destined for the mesh
  *
  * This call might reallocate skb data.
  *
  * Checks whether the given frame is a valid IGMP report.
  *
  * Return: If so then true, otherwise false.
  */
 static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
 {
     if (ip_mc_check_igmp(skb) < 0)
         return false;
 
     switch (igmp_hdr(skb)->type) {
     case IGMP_HOST_MEMBERSHIP_REPORT:
     case IGMPV2_HOST_MEMBERSHIP_REPORT:
     case IGMPV3_HOST_MEMBERSHIP_REPORT:
         return true;
     }
 
     return false;
 }
 
 /**
  * batadv_mcast_forw_mode_check_ipv4() - check for optimized forwarding
  *  potential
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the IPv4 packet to check
  * @is_unsnoopable: stores whether the destination is snoopable
  * @is_routable: stores whether the destination is routable
  *
  * Checks whether the given IPv4 packet has the potential to be forwarded with a
  * mode more optimal than classic flooding.
  *
  * Return: If so then 0. Otherwise -EINVAL or -ENOMEM in case of memory
  * allocation failure.
  */
 static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
                          struct sk_buff *skb,
                          bool *is_unsnoopable,
                          int *is_routable)
 {
     struct iphdr *iphdr;
 
     /* We might fail due to out-of-memory -> drop it */
     if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
         return -ENOMEM;
 
     if (batadv_mcast_is_report_ipv4(skb))
         return -EINVAL;
 
     iphdr = ip_hdr(skb);
 
     /* link-local multicast listeners behind a bridge are
      * not snoopable (see RFC4541, section 2.1.2.2)
      */
     if (ipv4_is_local_multicast(iphdr->daddr))
         *is_unsnoopable = true;
     else
         *is_routable = ETH_P_IP;
 
     return 0;
 }
 
 /**
  * batadv_mcast_is_report_ipv6() - check for MLD reports
  * @skb: the ethernet frame destined for the mesh
  *
  * This call might reallocate skb data.
  *
  * Checks whether the given frame is a valid MLD report.
  *
  * Return: If so then true, otherwise false.
  */
 static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
 {
     if (ipv6_mc_check_mld(skb) < 0)
         return false;
 
     switch (icmp6_hdr(skb)->icmp6_type) {
     case ICMPV6_MGM_REPORT:
     case ICMPV6_MLD2_REPORT:
         return true;
     }
 
     return false;
 }
 
 /**
  * batadv_mcast_forw_mode_check_ipv6() - check for optimized forwarding
  *  potential
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the IPv6 packet to check
  * @is_unsnoopable: stores whether the destination is snoopable
  * @is_routable: stores whether the destination is routable
  *
  * Checks whether the given IPv6 packet has the potential to be forwarded with a
  * mode more optimal than classic flooding.
  *
  * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
  */
 static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
                          struct sk_buff *skb,
                          bool *is_unsnoopable,
                          int *is_routable)
 {
     struct ipv6hdr *ip6hdr;
 
     /* We might fail due to out-of-memory -> drop it */
     if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
         return -ENOMEM;
 
     if (batadv_mcast_is_report_ipv6(skb))
         return -EINVAL;
 
     ip6hdr = ipv6_hdr(skb);
 
     if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) < IPV6_ADDR_SCOPE_LINKLOCAL)
         return -EINVAL;
 
     /* link-local-all-nodes multicast listeners behind a bridge are
      * not snoopable (see RFC4541, section 3, paragraph 3)
      */
     if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
         *is_unsnoopable = true;
     else if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) > IPV6_ADDR_SCOPE_LINKLOCAL)
         *is_routable = ETH_P_IPV6;
 
     return 0;
 }
 
 /**
  * batadv_mcast_forw_mode_check() - check for optimized forwarding potential
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast frame to check
  * @is_unsnoopable: stores whether the destination is snoopable
  * @is_routable: stores whether the destination is routable
  *
  * Checks whether the given multicast ethernet frame has the potential to be
  * forwarded with a mode more optimal than classic flooding.
  *
  * Return: If so then 0. Otherwise -EINVAL is or -ENOMEM if we are out of memory
  */
 static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
                     struct sk_buff *skb,
                     bool *is_unsnoopable,
                     int *is_routable)
 {
     struct ethhdr *ethhdr = eth_hdr(skb);
 
     if (!atomic_read(&bat_priv->multicast_mode))
         return -EINVAL;
 
     switch (ntohs(ethhdr->h_proto)) {
     case ETH_P_IP:
         return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
                              is_unsnoopable,
                              is_routable);
     case ETH_P_IPV6:
         if (!IS_ENABLED(CONFIG_IPV6))
             return -EINVAL;
 
         return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
                              is_unsnoopable,
                              is_routable);
     default:
         return -EINVAL;
     }
 }
 
 /**
  * batadv_mcast_forw_want_all_ip_count() - count nodes with unspecific mcast
  *  interest
  * @bat_priv: the bat priv with all the soft interface information
  * @ethhdr: ethernet header of a packet
  *
  * Return: the number of nodes which want all IPv4 multicast traffic if the
  * given ethhdr is from an IPv4 packet or the number of nodes which want all
  * IPv6 traffic if it matches an IPv6 packet.
  */
 static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv,
                            struct ethhdr *ethhdr)
 {
     switch (ntohs(ethhdr->h_proto)) {
     case ETH_P_IP:
         return atomic_read(&bat_priv->mcast.num_want_all_ipv4);
     case ETH_P_IPV6:
         return atomic_read(&bat_priv->mcast.num_want_all_ipv6);
     default:
         /* we shouldn't be here... */
         return 0;
     }
 }
 
 /**
  * batadv_mcast_forw_rtr_count() - count nodes with a multicast router
  * @bat_priv: the bat priv with all the soft interface information
  * @protocol: the ethernet protocol type to count multicast routers for
  *
  * Return: the number of nodes which want all routable IPv4 multicast traffic
  * if the protocol is ETH_P_IP or the number of nodes which want all routable
  * IPv6 traffic if the protocol is ETH_P_IPV6. Otherwise returns 0.
  */
 
 static int batadv_mcast_forw_rtr_count(struct batadv_priv *bat_priv,
                        int protocol)
 {
     switch (protocol) {
     case ETH_P_IP:
         return atomic_read(&bat_priv->mcast.num_want_all_rtr4);
     case ETH_P_IPV6:
         return atomic_read(&bat_priv->mcast.num_want_all_rtr6);
     default:
         return 0;
     }
 }
 
 /**
  * batadv_mcast_forw_tt_node_get() - get a multicast tt node
  * @bat_priv: the bat priv with all the soft interface information
  * @ethhdr: the ether header containing the multicast destination
  *
  * Return: an orig_node matching the multicast address provided by ethhdr
  * via a translation table lookup. This increases the returned nodes refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv,
                   struct ethhdr *ethhdr)
 {
     return batadv_transtable_search(bat_priv, NULL, ethhdr->h_dest,
                     BATADV_NO_FLAGS);
 }
 
 /**
  * batadv_mcast_forw_ipv4_node_get() - get a node with an ipv4 flag
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and
  * increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv)
 {
     struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(tmp_orig_node,
                  &bat_priv->mcast.want_all_ipv4_list,
                  mcast_want_all_ipv4_node) {
         if (!kref_get_unless_zero(&tmp_orig_node->refcount))
             continue;
 
         orig_node = tmp_orig_node;
         break;
     }
     rcu_read_unlock();
 
     return orig_node;
 }
 
 /**
  * batadv_mcast_forw_ipv6_node_get() - get a node with an ipv6 flag
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set
  * and increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv)
 {
     struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(tmp_orig_node,
                  &bat_priv->mcast.want_all_ipv6_list,
                  mcast_want_all_ipv6_node) {
         if (!kref_get_unless_zero(&tmp_orig_node->refcount))
             continue;
 
         orig_node = tmp_orig_node;
         break;
     }
     rcu_read_unlock();
 
     return orig_node;
 }
 
 /**
  * batadv_mcast_forw_ip_node_get() - get a node with an ipv4/ipv6 flag
  * @bat_priv: the bat priv with all the soft interface information
  * @ethhdr: an ethernet header to determine the protocol family from
  *
  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or
  * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, sets and
  * increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv,
                   struct ethhdr *ethhdr)
 {
     switch (ntohs(ethhdr->h_proto)) {
     case ETH_P_IP:
         return batadv_mcast_forw_ipv4_node_get(bat_priv);
     case ETH_P_IPV6:
         return batadv_mcast_forw_ipv6_node_get(bat_priv);
     default:
         /* we shouldn't be here... */
         return NULL;
     }
 }
 
 /**
  * batadv_mcast_forw_unsnoop_node_get() - get a node with an unsnoopable flag
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
  * set and increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
 {
     struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(tmp_orig_node,
                  &bat_priv->mcast.want_all_unsnoopables_list,
                  mcast_want_all_unsnoopables_node) {
         if (!kref_get_unless_zero(&tmp_orig_node->refcount))
             continue;
 
         orig_node = tmp_orig_node;
         break;
     }
     rcu_read_unlock();
 
     return orig_node;
 }
 
 /**
  * batadv_mcast_forw_rtr4_node_get() - get a node with an ipv4 mcast router flag
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR4 flag unset and
  * increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_rtr4_node_get(struct batadv_priv *bat_priv)
 {
     struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(tmp_orig_node,
                  &bat_priv->mcast.want_all_rtr4_list,
                  mcast_want_all_rtr4_node) {
         if (!kref_get_unless_zero(&tmp_orig_node->refcount))
             continue;
 
         orig_node = tmp_orig_node;
         break;
     }
     rcu_read_unlock();
 
     return orig_node;
 }
 
 /**
  * batadv_mcast_forw_rtr6_node_get() - get a node with an ipv6 mcast router flag
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: an orig_node which has the BATADV_MCAST_WANT_NO_RTR6 flag unset
  * and increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_rtr6_node_get(struct batadv_priv *bat_priv)
 {
     struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(tmp_orig_node,
                  &bat_priv->mcast.want_all_rtr6_list,
                  mcast_want_all_rtr6_node) {
         if (!kref_get_unless_zero(&tmp_orig_node->refcount))
             continue;
 
         orig_node = tmp_orig_node;
         break;
     }
     rcu_read_unlock();
 
     return orig_node;
 }
 
 /**
  * batadv_mcast_forw_rtr_node_get() - get a node with an ipv4/ipv6 router flag
  * @bat_priv: the bat priv with all the soft interface information
  * @ethhdr: an ethernet header to determine the protocol family from
  *
  * Return: an orig_node which has no BATADV_MCAST_WANT_NO_RTR4 or
  * BATADV_MCAST_WANT_NO_RTR6 flag, depending on the provided ethhdr, set and
  * increases its refcount.
  */
 static struct batadv_orig_node *
 batadv_mcast_forw_rtr_node_get(struct batadv_priv *bat_priv,
                    struct ethhdr *ethhdr)
 {
     switch (ntohs(ethhdr->h_proto)) {
     case ETH_P_IP:
         return batadv_mcast_forw_rtr4_node_get(bat_priv);
     case ETH_P_IPV6:
         return batadv_mcast_forw_rtr6_node_get(bat_priv);
     default:
         /* we shouldn't be here... */
         return NULL;
     }
 }
 
 /**
  * batadv_mcast_forw_mode() - check on how to forward a multicast packet
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: The multicast packet to check
  * @orig: an originator to be set to forward the skb to
  * @is_routable: stores whether the destination is routable
  *
  * Return: the forwarding mode as enum batadv_forw_mode and in case of
  * BATADV_FORW_SINGLE set the orig to the single originator the skb
  * should be forwarded to.
  */
 enum batadv_forw_mode
 batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
                struct batadv_orig_node **orig, int *is_routable)
 {
     int ret, tt_count, ip_count, unsnoop_count, total_count;
     bool is_unsnoopable = false;
     unsigned int mcast_fanout;
     struct ethhdr *ethhdr;
     int rtr_count = 0;
 
     ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable,
                        is_routable);
     if (ret == -ENOMEM)
         return BATADV_FORW_NONE;
     else if (ret < 0)
         return BATADV_FORW_ALL;
 
     ethhdr = eth_hdr(skb);
 
     tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
                            BATADV_NO_FLAGS);
     ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr);
     unsnoop_count = !is_unsnoopable ? 0 :
             atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
     rtr_count = batadv_mcast_forw_rtr_count(bat_priv, *is_routable);
 
     total_count = tt_count + ip_count + unsnoop_count + rtr_count;
 
     switch (total_count) {
     case 1:
         if (tt_count)
             *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
         else if (ip_count)
             *orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr);
         else if (unsnoop_count)
             *orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
         else if (rtr_count)
             *orig = batadv_mcast_forw_rtr_node_get(bat_priv,
                                    ethhdr);
 
         if (*orig)
             return BATADV_FORW_SINGLE;
 
         fallthrough;
     case 0:
         return BATADV_FORW_NONE;
     default:
         mcast_fanout = atomic_read(&bat_priv->multicast_fanout);
 
         if (!unsnoop_count && total_count <= mcast_fanout)
             return BATADV_FORW_SOME;
     }
 
     return BATADV_FORW_ALL;
 }
 
 /**
  * batadv_mcast_forw_send_orig() - send a multicast packet to an originator
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to send
  * @vid: the vlan identifier
  * @orig_node: the originator to send the packet to
  *
  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
  */
 int batadv_mcast_forw_send_orig(struct batadv_priv *bat_priv,
                 struct sk_buff *skb,
                 unsigned short vid,
                 struct batadv_orig_node *orig_node)
 {
     /* Avoid sending multicast-in-unicast packets to other BLA
      * gateways - they already got the frame from the LAN side
      * we share with them.
      * TODO: Refactor to take BLA into account earlier, to avoid
      * reducing the mcast_fanout count.
      */
     if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid)) {
         dev_kfree_skb(skb);
         return NET_XMIT_SUCCESS;
     }
 
     return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST, 0,
                        orig_node, vid);
 }
 
 /**
  * batadv_mcast_forw_tt() - forwards a packet to multicast listeners
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any multicast
  * listener registered in the translation table. A transmission is performed
  * via a batman-adv unicast packet for each such destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
  * otherwise.
  */
 static int
 batadv_mcast_forw_tt(struct batadv_priv *bat_priv, struct sk_buff *skb,
              unsigned short vid)
 {
     int ret = NET_XMIT_SUCCESS;
     struct sk_buff *newskb;
 
     struct batadv_tt_orig_list_entry *orig_entry;
 
     struct batadv_tt_global_entry *tt_global;
     const u8 *addr = eth_hdr(skb)->h_dest;
 
     tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
     if (!tt_global)
         goto out;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(orig_entry, &tt_global->orig_list, list) {
         newskb = skb_copy(skb, GFP_ATOMIC);
         if (!newskb) {
             ret = NET_XMIT_DROP;
             break;
         }
 
         batadv_mcast_forw_send_orig(bat_priv, newskb, vid,
                         orig_entry->orig_node);
     }
     rcu_read_unlock();
 
     batadv_tt_global_entry_put(tt_global);
 
 out:
     return ret;
 }
 
 /**
  * batadv_mcast_forw_want_all_ipv4() - forward to nodes with want-all-ipv4
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any node with a
  * BATADV_MCAST_WANT_ALL_IPV4 flag set. A transmission is performed via a
  * batman-adv unicast packet for each such destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
  * otherwise.
  */
 static int
 batadv_mcast_forw_want_all_ipv4(struct batadv_priv *bat_priv,
                 struct sk_buff *skb, unsigned short vid)
 {
     struct batadv_orig_node *orig_node;
     int ret = NET_XMIT_SUCCESS;
     struct sk_buff *newskb;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(orig_node,
                  &bat_priv->mcast.want_all_ipv4_list,
                  mcast_want_all_ipv4_node) {
         newskb = skb_copy(skb, GFP_ATOMIC);
         if (!newskb) {
             ret = NET_XMIT_DROP;
             break;
         }
 
         batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
     }
     rcu_read_unlock();
     return ret;
 }
 
 /**
  * batadv_mcast_forw_want_all_ipv6() - forward to nodes with want-all-ipv6
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: The multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any node with a
  * BATADV_MCAST_WANT_ALL_IPV6 flag set. A transmission is performed via a
  * batman-adv unicast packet for each such destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
  * otherwise.
  */
 static int
 batadv_mcast_forw_want_all_ipv6(struct batadv_priv *bat_priv,
                 struct sk_buff *skb, unsigned short vid)
 {
     struct batadv_orig_node *orig_node;
     int ret = NET_XMIT_SUCCESS;
     struct sk_buff *newskb;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(orig_node,
                  &bat_priv->mcast.want_all_ipv6_list,
                  mcast_want_all_ipv6_node) {
         newskb = skb_copy(skb, GFP_ATOMIC);
         if (!newskb) {
             ret = NET_XMIT_DROP;
             break;
         }
 
         batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
     }
     rcu_read_unlock();
     return ret;
 }
 
 /**
  * batadv_mcast_forw_want_all() - forward packet to nodes in a want-all list
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any node with a
  * BATADV_MCAST_WANT_ALL_IPV4 or BATADV_MCAST_WANT_ALL_IPV6 flag set. A
  * transmission is performed via a batman-adv unicast packet for each such
  * destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
  * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
  */
 static int
 batadv_mcast_forw_want_all(struct batadv_priv *bat_priv,
                struct sk_buff *skb, unsigned short vid)
 {
     switch (ntohs(eth_hdr(skb)->h_proto)) {
     case ETH_P_IP:
         return batadv_mcast_forw_want_all_ipv4(bat_priv, skb, vid);
     case ETH_P_IPV6:
         return batadv_mcast_forw_want_all_ipv6(bat_priv, skb, vid);
     default:
         /* we shouldn't be here... */
         return NET_XMIT_DROP;
     }
 }
 
 /**
  * batadv_mcast_forw_want_all_rtr4() - forward to nodes with want-all-rtr4
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any node with a
  * BATADV_MCAST_WANT_NO_RTR4 flag unset. A transmission is performed via a
  * batman-adv unicast packet for each such destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
  * otherwise.
  */
 static int
 batadv_mcast_forw_want_all_rtr4(struct batadv_priv *bat_priv,
                 struct sk_buff *skb, unsigned short vid)
 {
     struct batadv_orig_node *orig_node;
     int ret = NET_XMIT_SUCCESS;
     struct sk_buff *newskb;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(orig_node,
                  &bat_priv->mcast.want_all_rtr4_list,
                  mcast_want_all_rtr4_node) {
         newskb = skb_copy(skb, GFP_ATOMIC);
         if (!newskb) {
             ret = NET_XMIT_DROP;
             break;
         }
 
         batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
     }
     rcu_read_unlock();
     return ret;
 }
 
 /**
  * batadv_mcast_forw_want_all_rtr6() - forward to nodes with want-all-rtr6
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: The multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any node with a
  * BATADV_MCAST_WANT_NO_RTR6 flag unset. A transmission is performed via a
  * batman-adv unicast packet for each such destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure, NET_XMIT_SUCCESS
  * otherwise.
  */
 static int
 batadv_mcast_forw_want_all_rtr6(struct batadv_priv *bat_priv,
                 struct sk_buff *skb, unsigned short vid)
 {
     struct batadv_orig_node *orig_node;
     int ret = NET_XMIT_SUCCESS;
     struct sk_buff *newskb;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(orig_node,
                  &bat_priv->mcast.want_all_rtr6_list,
                  mcast_want_all_rtr6_node) {
         newskb = skb_copy(skb, GFP_ATOMIC);
         if (!newskb) {
             ret = NET_XMIT_DROP;
             break;
         }
 
         batadv_mcast_forw_send_orig(bat_priv, newskb, vid, orig_node);
     }
     rcu_read_unlock();
     return ret;
 }
 
 /**
  * batadv_mcast_forw_want_rtr() - forward packet to nodes in a want-all-rtr list
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to transmit
  * @vid: the vlan identifier
  *
  * Sends copies of a frame with multicast destination to any node with a
  * BATADV_MCAST_WANT_NO_RTR4 or BATADV_MCAST_WANT_NO_RTR6 flag unset. A
  * transmission is performed via a batman-adv unicast packet for each such
  * destination node.
  *
  * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
  * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
  */
 static int
 batadv_mcast_forw_want_rtr(struct batadv_priv *bat_priv,
                struct sk_buff *skb, unsigned short vid)
 {
     switch (ntohs(eth_hdr(skb)->h_proto)) {
     case ETH_P_IP:
         return batadv_mcast_forw_want_all_rtr4(bat_priv, skb, vid);
     case ETH_P_IPV6:
         return batadv_mcast_forw_want_all_rtr6(bat_priv, skb, vid);
     default:
         /* we shouldn't be here... */
         return NET_XMIT_DROP;
     }
 }
 
 /**
  * batadv_mcast_forw_send() - send packet to any detected multicast recipient
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast packet to transmit
  * @vid: the vlan identifier
  * @is_routable: stores whether the destination is routable
  *
  * Sends copies of a frame with multicast destination to any node that signaled
  * interest in it, that is either via the translation table or the according
  * want-all flags. A transmission is performed via a batman-adv unicast packet
  * for each such destination node.
  *
  * The given skb is consumed/freed.
  *
  * Return: NET_XMIT_DROP on memory allocation failure or if the protocol family
  * is neither IPv4 nor IPv6. NET_XMIT_SUCCESS otherwise.
  */
 int batadv_mcast_forw_send(struct batadv_priv *bat_priv, struct sk_buff *skb,
                unsigned short vid, int is_routable)
 {
     int ret;
 
     ret = batadv_mcast_forw_tt(bat_priv, skb, vid);
     if (ret != NET_XMIT_SUCCESS) {
         kfree_skb(skb);
         return ret;
     }
 
     ret = batadv_mcast_forw_want_all(bat_priv, skb, vid);
     if (ret != NET_XMIT_SUCCESS) {
         kfree_skb(skb);
         return ret;
     }
 
     if (!is_routable)
         goto skip_mc_router;
 
     ret = batadv_mcast_forw_want_rtr(bat_priv, skb, vid);
     if (ret != NET_XMIT_SUCCESS) {
         kfree_skb(skb);
         return ret;
     }
 
 skip_mc_router:
     consume_skb(skb);
     return ret;
 }
 
 /**
  * batadv_mcast_want_unsnoop_update() - update unsnoop counter and list
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node which multicast state might have changed of
  * @mcast_flags: flags indicating the new multicast state
  *
  * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
  * orig, has toggled then this method updates the counter and the list
  * accordingly.
  *
  * Caller needs to hold orig->mcast_handler_lock.
  */
 static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
                          struct batadv_orig_node *orig,
                          u8 mcast_flags)
 {
     struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
     struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;
 
     lockdep_assert_held(&orig->mcast_handler_lock);
 
     /* switched from flag unset to set */
     if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
         !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
         atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(!hlist_unhashed(node));
 
         hlist_add_head_rcu(node, head);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     /* switched from flag set to unset */
     } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
            orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
         atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(hlist_unhashed(node));
 
         hlist_del_init_rcu(node);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     }
 }
 
 /**
  * batadv_mcast_want_ipv4_update() - update want-all-ipv4 counter and list
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node which multicast state might have changed of
  * @mcast_flags: flags indicating the new multicast state
  *
  * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has
  * toggled then this method updates the counter and the list accordingly.
  *
  * Caller needs to hold orig->mcast_handler_lock.
  */
 static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig,
                       u8 mcast_flags)
 {
     struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
     struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;
 
     lockdep_assert_held(&orig->mcast_handler_lock);
 
     /* switched from flag unset to set */
     if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 &&
         !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) {
         atomic_inc(&bat_priv->mcast.num_want_all_ipv4);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(!hlist_unhashed(node));
 
         hlist_add_head_rcu(node, head);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     /* switched from flag set to unset */
     } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) &&
            orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) {
         atomic_dec(&bat_priv->mcast.num_want_all_ipv4);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(hlist_unhashed(node));
 
         hlist_del_init_rcu(node);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     }
 }
 
 /**
  * batadv_mcast_want_ipv6_update() - update want-all-ipv6 counter and list
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node which multicast state might have changed of
  * @mcast_flags: flags indicating the new multicast state
  *
  * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has
  * toggled then this method updates the counter and the list accordingly.
  *
  * Caller needs to hold orig->mcast_handler_lock.
  */
 static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig,
                       u8 mcast_flags)
 {
     struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
     struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;
 
     lockdep_assert_held(&orig->mcast_handler_lock);
 
     /* switched from flag unset to set */
     if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 &&
         !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) {
         atomic_inc(&bat_priv->mcast.num_want_all_ipv6);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(!hlist_unhashed(node));
 
         hlist_add_head_rcu(node, head);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     /* switched from flag set to unset */
     } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) &&
            orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) {
         atomic_dec(&bat_priv->mcast.num_want_all_ipv6);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(hlist_unhashed(node));
 
         hlist_del_init_rcu(node);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     }
 }
 
 /**
  * batadv_mcast_want_rtr4_update() - update want-all-rtr4 counter and list
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node which multicast state might have changed of
  * @mcast_flags: flags indicating the new multicast state
  *
  * If the BATADV_MCAST_WANT_NO_RTR4 flag of this originator, orig, has
  * toggled then this method updates the counter and the list accordingly.
  *
  * Caller needs to hold orig->mcast_handler_lock.
  */
 static void batadv_mcast_want_rtr4_update(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig,
                       u8 mcast_flags)
 {
     struct hlist_node *node = &orig->mcast_want_all_rtr4_node;
     struct hlist_head *head = &bat_priv->mcast.want_all_rtr4_list;
 
     lockdep_assert_held(&orig->mcast_handler_lock);
 
     /* switched from flag set to unset */
     if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR4) &&
         orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4) {
         atomic_inc(&bat_priv->mcast.num_want_all_rtr4);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(!hlist_unhashed(node));
 
         hlist_add_head_rcu(node, head);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     /* switched from flag unset to set */
     } else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR4 &&
            !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR4)) {
         atomic_dec(&bat_priv->mcast.num_want_all_rtr4);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(hlist_unhashed(node));
 
         hlist_del_init_rcu(node);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     }
 }
 
 /**
  * batadv_mcast_want_rtr6_update() - update want-all-rtr6 counter and list
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node which multicast state might have changed of
  * @mcast_flags: flags indicating the new multicast state
  *
  * If the BATADV_MCAST_WANT_NO_RTR6 flag of this originator, orig, has
  * toggled then this method updates the counter and the list accordingly.
  *
  * Caller needs to hold orig->mcast_handler_lock.
  */
 static void batadv_mcast_want_rtr6_update(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig,
                       u8 mcast_flags)
 {
     struct hlist_node *node = &orig->mcast_want_all_rtr6_node;
     struct hlist_head *head = &bat_priv->mcast.want_all_rtr6_list;
 
     lockdep_assert_held(&orig->mcast_handler_lock);
 
     /* switched from flag set to unset */
     if (!(mcast_flags & BATADV_MCAST_WANT_NO_RTR6) &&
         orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6) {
         atomic_inc(&bat_priv->mcast.num_want_all_rtr6);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(!hlist_unhashed(node));
 
         hlist_add_head_rcu(node, head);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     /* switched from flag unset to set */
     } else if (mcast_flags & BATADV_MCAST_WANT_NO_RTR6 &&
            !(orig->mcast_flags & BATADV_MCAST_WANT_NO_RTR6)) {
         atomic_dec(&bat_priv->mcast.num_want_all_rtr6);
 
         spin_lock_bh(&bat_priv->mcast.want_lists_lock);
         /* flag checks above + mcast_handler_lock prevents this */
         WARN_ON(hlist_unhashed(node));
 
         hlist_del_init_rcu(node);
         spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
     }
 }
 
 /**
  * batadv_mcast_tvlv_flags_get() - get multicast flags from an OGM TVLV
  * @enabled: whether the originator has multicast TVLV support enabled
  * @tvlv_value: tvlv buffer containing the multicast flags
  * @tvlv_value_len: tvlv buffer length
  *
  * Return: multicast flags for the given tvlv buffer
  */
 static u8
 batadv_mcast_tvlv_flags_get(bool enabled, void *tvlv_value, u16 tvlv_value_len)
 {
     u8 mcast_flags = BATADV_NO_FLAGS;
 
     if (enabled && tvlv_value && tvlv_value_len >= sizeof(mcast_flags))
         mcast_flags = *(u8 *)tvlv_value;
 
     if (!enabled) {
         mcast_flags |= BATADV_MCAST_WANT_ALL_IPV4;
         mcast_flags |= BATADV_MCAST_WANT_ALL_IPV6;
     }
 
     /* remove redundant flags to avoid sending duplicate packets later */
     if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)
         mcast_flags |= BATADV_MCAST_WANT_NO_RTR4;
 
     if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)
         mcast_flags |= BATADV_MCAST_WANT_NO_RTR6;
 
     return mcast_flags;
 }
 
 /**
  * batadv_mcast_tvlv_ogm_handler() - process incoming multicast tvlv container
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node of the ogm
  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
  * @tvlv_value: tvlv buffer containing the multicast data
  * @tvlv_value_len: tvlv buffer length
  */
 static void batadv_mcast_tvlv_ogm_handler(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig,
                       u8 flags,
                       void *tvlv_value,
                       u16 tvlv_value_len)
 {
     bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
     u8 mcast_flags;
 
     mcast_flags = batadv_mcast_tvlv_flags_get(orig_mcast_enabled,
                           tvlv_value, tvlv_value_len);
 
     spin_lock_bh(&orig->mcast_handler_lock);
 
     if (orig_mcast_enabled &&
         !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
         set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
     } else if (!orig_mcast_enabled &&
            test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
         clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
     }
 
     set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);
 
     batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
     batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags);
     batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags);
     batadv_mcast_want_rtr4_update(bat_priv, orig, mcast_flags);
     batadv_mcast_want_rtr6_update(bat_priv, orig, mcast_flags);
 
     orig->mcast_flags = mcast_flags;
     spin_unlock_bh(&orig->mcast_handler_lock);
 }
 
 /**
  * batadv_mcast_init() - initialize the multicast optimizations structures
  * @bat_priv: the bat priv with all the soft interface information
  */
 void batadv_mcast_init(struct batadv_priv *bat_priv)
 {
     batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler,
                      NULL, BATADV_TVLV_MCAST, 2,
                      BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
 
     INIT_DELAYED_WORK(&bat_priv->mcast.work, batadv_mcast_mla_update);
     batadv_mcast_start_timer(bat_priv);
 }
 
 /**
  * batadv_mcast_mesh_info_put() - put multicast info into a netlink message
  * @msg: buffer for the message
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: 0 or error code.
  */
 int batadv_mcast_mesh_info_put(struct sk_buff *msg,
                    struct batadv_priv *bat_priv)
 {
     u32 flags = bat_priv->mcast.mla_flags.tvlv_flags;
     u32 flags_priv = BATADV_NO_FLAGS;
 
     if (bat_priv->mcast.mla_flags.bridged) {
         flags_priv |= BATADV_MCAST_FLAGS_BRIDGED;
 
         if (bat_priv->mcast.mla_flags.querier_ipv4.exists)
             flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_EXISTS;
         if (bat_priv->mcast.mla_flags.querier_ipv6.exists)
             flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_EXISTS;
         if (bat_priv->mcast.mla_flags.querier_ipv4.shadowing)
             flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV4_SHADOWING;
         if (bat_priv->mcast.mla_flags.querier_ipv6.shadowing)
             flags_priv |= BATADV_MCAST_FLAGS_QUERIER_IPV6_SHADOWING;
     }
 
     if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS, flags) ||
         nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS_PRIV, flags_priv))
         return -EMSGSIZE;
 
     return 0;
 }
 
 /**
  * batadv_mcast_flags_dump_entry() - dump one entry of the multicast flags table
  *  to a netlink socket
  * @msg: buffer for the message
  * @portid: netlink port
  * @cb: Control block containing additional options
  * @orig_node: originator to dump the multicast flags of
  *
  * Return: 0 or error code.
  */
 static int
 batadv_mcast_flags_dump_entry(struct sk_buff *msg, u32 portid,
                   struct netlink_callback *cb,
                   struct batadv_orig_node *orig_node)
 {
     void *hdr;
 
     hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
               &batadv_netlink_family, NLM_F_MULTI,
               BATADV_CMD_GET_MCAST_FLAGS);
     if (!hdr)
         return -ENOBUFS;
 
     genl_dump_check_consistent(cb, hdr);
 
     if (nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
             orig_node->orig)) {
         genlmsg_cancel(msg, hdr);
         return -EMSGSIZE;
     }
 
     if (test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
              &orig_node->capabilities)) {
         if (nla_put_u32(msg, BATADV_ATTR_MCAST_FLAGS,
                 orig_node->mcast_flags)) {
             genlmsg_cancel(msg, hdr);
             return -EMSGSIZE;
         }
     }
 
     genlmsg_end(msg, hdr);
     return 0;
 }
 
 /**
  * batadv_mcast_flags_dump_bucket() - dump one bucket of the multicast flags
  *  table to a netlink socket
  * @msg: buffer for the message
  * @portid: netlink port
  * @cb: Control block containing additional options
  * @hash: hash to dump
  * @bucket: bucket index to dump
  * @idx_skip: How many entries to skip
  *
  * Return: 0 or error code.
  */
 static int
 batadv_mcast_flags_dump_bucket(struct sk_buff *msg, u32 portid,
                    struct netlink_callback *cb,
                    struct batadv_hashtable *hash,
                    unsigned int bucket, long *idx_skip)
 {
     struct batadv_orig_node *orig_node;
     long idx = 0;
 
     spin_lock_bh(&hash->list_locks[bucket]);
     cb->seq = atomic_read(&hash->generation) << 1 | 1;
 
     hlist_for_each_entry(orig_node, &hash->table[bucket], hash_entry) {
         if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
                   &orig_node->capa_initialized))
             continue;
 
         if (idx < *idx_skip)
             goto skip;
 
         if (batadv_mcast_flags_dump_entry(msg, portid, cb, orig_node)) {
             spin_unlock_bh(&hash->list_locks[bucket]);
             *idx_skip = idx;
 
             return -EMSGSIZE;
         }
 
 skip:
         idx++;
     }
     spin_unlock_bh(&hash->list_locks[bucket]);
 
     return 0;
 }
 
 /**
  * __batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
  * @msg: buffer for the message
  * @portid: netlink port
  * @cb: Control block containing additional options
  * @bat_priv: the bat priv with all the soft interface information
  * @bucket: current bucket to dump
  * @idx: index in current bucket to the next entry to dump
  *
  * Return: 0 or error code.
  */
 static int
 __batadv_mcast_flags_dump(struct sk_buff *msg, u32 portid,
               struct netlink_callback *cb,
               struct batadv_priv *bat_priv, long *bucket, long *idx)
 {
     struct batadv_hashtable *hash = bat_priv->orig_hash;
     long bucket_tmp = *bucket;
     long idx_tmp = *idx;
 
     while (bucket_tmp < hash->size) {
         if (batadv_mcast_flags_dump_bucket(msg, portid, cb, hash,
                            bucket_tmp, &idx_tmp))
             break;
 
         bucket_tmp++;
         idx_tmp = 0;
     }
 
     *bucket = bucket_tmp;
     *idx = idx_tmp;
 
     return msg->len;
 }
 
 /**
  * batadv_mcast_netlink_get_primary() - get primary interface from netlink
  *  callback
  * @cb: netlink callback structure
  * @primary_if: the primary interface pointer to return the result in
  *
  * Return: 0 or error code.
  */
 static int
 batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
                  struct batadv_hard_iface **primary_if)
 {
     struct batadv_hard_iface *hard_iface = NULL;
     struct net *net = sock_net(cb->skb->sk);
     struct net_device *soft_iface;
     struct batadv_priv *bat_priv;
     int ifindex;
     int ret = 0;
 
     ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
     if (!ifindex)
         return -EINVAL;
 
     soft_iface = dev_get_by_index(net, ifindex);
     if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
         ret = -ENODEV;
         goto out;
     }
 
     bat_priv = netdev_priv(soft_iface);
 
     hard_iface = batadv_primary_if_get_selected(bat_priv);
     if (!hard_iface || hard_iface->if_status != BATADV_IF_ACTIVE) {
         ret = -ENOENT;
         goto out;
     }
 
 out:
     dev_put(soft_iface);
 
     if (!ret && primary_if)
         *primary_if = hard_iface;
     else
         batadv_hardif_put(hard_iface);
 
     return ret;
 }
 
 /**
  * batadv_mcast_flags_dump() - dump multicast flags table to a netlink socket
  * @msg: buffer for the message
  * @cb: callback structure containing arguments
  *
  * Return: message length.
  */
 int batadv_mcast_flags_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
     struct batadv_hard_iface *primary_if = NULL;
     int portid = NETLINK_CB(cb->skb).portid;
     struct batadv_priv *bat_priv;
     long *bucket = &cb->args[0];
     long *idx = &cb->args[1];
     int ret;
 
     ret = batadv_mcast_netlink_get_primary(cb, &primary_if);
     if (ret)
         return ret;
 
     bat_priv = netdev_priv(primary_if->soft_iface);
     ret = __batadv_mcast_flags_dump(msg, portid, cb, bat_priv, bucket, idx);
 
     batadv_hardif_put(primary_if);
     return ret;
 }
 
 /**
  * batadv_mcast_free() - free the multicast optimizations structures
  * @bat_priv: the bat priv with all the soft interface information
  */
 void batadv_mcast_free(struct batadv_priv *bat_priv)
 {
     cancel_delayed_work_sync(&bat_priv->mcast.work);
 
     batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
     batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
 
     /* safely calling outside of worker, as worker was canceled above */
     batadv_mcast_mla_tt_retract(bat_priv, NULL);
 }
 
 /**
  * batadv_mcast_purge_orig() - reset originator global mcast state modifications
  * @orig: the originator which is going to get purged
  */
 void batadv_mcast_purge_orig(struct batadv_orig_node *orig)
 {
     struct batadv_priv *bat_priv = orig->bat_priv;
 
     spin_lock_bh(&orig->mcast_handler_lock);
 
     batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
     batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS);
     batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS);
     batadv_mcast_want_rtr4_update(bat_priv, orig,
                       BATADV_MCAST_WANT_NO_RTR4);
     batadv_mcast_want_rtr6_update(bat_priv, orig,
                       BATADV_MCAST_WANT_NO_RTR6);
 
     spin_unlock_bh(&orig->mcast_handler_lock);
 }

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