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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-only
 /*
  * Interface handling
  *
  * Copyright 2002-2005, Instant802 Networks, Inc.
  * Copyright 2005-2006, Devicescape Software, Inc.
  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
  * Copyright (c) 2016        Intel Deutschland GmbH
  * Copyright (C) 2018-2022 Intel Corporation
  */
 #include <linux/slab.h>
 #include <linux/kernel.h>
 #include <linux/if_arp.h>
 #include <linux/netdevice.h>
 #include <linux/rtnetlink.h>
 #include <linux/kcov.h>
 #include <net/mac80211.h>
 #include <net/ieee80211_radiotap.h>
 #include "ieee80211_i.h"
 #include "sta_info.h"
 #include "debugfs_netdev.h"
 #include "mesh.h"
 #include "led.h"
 #include "driver-ops.h"
 #include "wme.h"
 #include "rate.h"
 
 /**
  * DOC: Interface list locking
  *
  * The interface list in each struct ieee80211_local is protected
  * three-fold:
  *
  * (1) modifications may only be done under the RTNL
  * (2) modifications and readers are protected against each other by
  *     the iflist_mtx.
  * (3) modifications are done in an RCU manner so atomic readers
  *     can traverse the list in RCU-safe blocks.
  *
  * As a consequence, reads (traversals) of the list can be protected
  * by either the RTNL, the iflist_mtx or RCU.
  */
 
 static void ieee80211_iface_work(struct work_struct *work);
 
 bool __ieee80211_recalc_txpower(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_chanctx_conf *chanctx_conf;
     int power;
 
     rcu_read_lock();
     chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
     if (!chanctx_conf) {
         rcu_read_unlock();
         return false;
     }
 
     power = ieee80211_chandef_max_power(&chanctx_conf->def);
     rcu_read_unlock();
 
     if (sdata->deflink.user_power_level != IEEE80211_UNSET_POWER_LEVEL)
         power = min(power, sdata->deflink.user_power_level);
 
     if (sdata->deflink.ap_power_level != IEEE80211_UNSET_POWER_LEVEL)
         power = min(power, sdata->deflink.ap_power_level);
 
     if (power != sdata->vif.bss_conf.txpower) {
         sdata->vif.bss_conf.txpower = power;
         ieee80211_hw_config(sdata->local, 0);
         return true;
     }
 
     return false;
 }
 
 void ieee80211_recalc_txpower(struct ieee80211_sub_if_data *sdata,
                   bool update_bss)
 {
     if (__ieee80211_recalc_txpower(sdata) ||
         (update_bss && ieee80211_sdata_running(sdata)))
         ieee80211_link_info_change_notify(sdata, &sdata->deflink,
                           BSS_CHANGED_TXPOWER);
 }
 
 static u32 __ieee80211_idle_off(struct ieee80211_local *local)
 {
     if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
         return 0;
 
     local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
     return IEEE80211_CONF_CHANGE_IDLE;
 }
 
 static u32 __ieee80211_idle_on(struct ieee80211_local *local)
 {
     if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
         return 0;
 
     ieee80211_flush_queues(local, NULL, false);
 
     local->hw.conf.flags |= IEEE80211_CONF_IDLE;
     return IEEE80211_CONF_CHANGE_IDLE;
 }
 
 static u32 __ieee80211_recalc_idle(struct ieee80211_local *local,
                    bool force_active)
 {
     bool working, scanning, active;
     unsigned int led_trig_start = 0, led_trig_stop = 0;
 
     lockdep_assert_held(&local->mtx);
 
     active = force_active ||
          !list_empty(&local->chanctx_list) ||
          local->monitors;
 
     working = !local->ops->remain_on_channel &&
           !list_empty(&local->roc_list);
 
     scanning = test_bit(SCAN_SW_SCANNING, &local->scanning) ||
            test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
 
     if (working || scanning)
         led_trig_start |= IEEE80211_TPT_LEDTRIG_FL_WORK;
     else
         led_trig_stop |= IEEE80211_TPT_LEDTRIG_FL_WORK;
 
     if (active)
         led_trig_start |= IEEE80211_TPT_LEDTRIG_FL_CONNECTED;
     else
         led_trig_stop |= IEEE80211_TPT_LEDTRIG_FL_CONNECTED;
 
     ieee80211_mod_tpt_led_trig(local, led_trig_start, led_trig_stop);
 
     if (working || scanning || active)
         return __ieee80211_idle_off(local);
     return __ieee80211_idle_on(local);
 }
 
 u32 ieee80211_idle_off(struct ieee80211_local *local)
 {
     return __ieee80211_recalc_idle(local, true);
 }
 
 void ieee80211_recalc_idle(struct ieee80211_local *local)
 {
     u32 change = __ieee80211_recalc_idle(local, false);
     if (change)
         ieee80211_hw_config(local, change);
 }
 
 static int ieee80211_verify_mac(struct ieee80211_sub_if_data *sdata, u8 *addr,
                 bool check_dup)
 {
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_sub_if_data *iter;
     u64 new, mask, tmp;
     u8 *m;
     int ret = 0;
 
     if (is_zero_ether_addr(local->hw.wiphy->addr_mask))
         return 0;
 
     m = addr;
     new =   ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
         ((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
         ((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
 
     m = local->hw.wiphy->addr_mask;
     mask =  ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
         ((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
         ((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
 
     if (!check_dup)
         return ret;
 
     mutex_lock(&local->iflist_mtx);
     list_for_each_entry(iter, &local->interfaces, list) {
         if (iter == sdata)
             continue;
 
         if (iter->vif.type == NL80211_IFTYPE_MONITOR &&
             !(iter->u.mntr.flags & MONITOR_FLAG_ACTIVE))
             continue;
 
         m = iter->vif.addr;
         tmp =   ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
             ((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
             ((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
 
         if ((new & ~mask) != (tmp & ~mask)) {
             ret = -EINVAL;
             break;
         }
     }
     mutex_unlock(&local->iflist_mtx);
 
     return ret;
 }
 
 static int ieee80211_change_mac(struct net_device *dev, void *addr)
 {
     struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
     struct sockaddr *sa = addr;
     bool check_dup = true;
     int ret;
 
     if (ieee80211_sdata_running(sdata))
         return -EBUSY;
 
     if (sdata->vif.type == NL80211_IFTYPE_MONITOR &&
         !(sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE))
         check_dup = false;
 
     ret = ieee80211_verify_mac(sdata, sa->sa_data, check_dup);
     if (ret)
         return ret;
 
     ret = eth_mac_addr(dev, sa);
 
     if (ret == 0) {
         memcpy(sdata->vif.addr, sa->sa_data, ETH_ALEN);
         ether_addr_copy(sdata->vif.bss_conf.addr, sdata->vif.addr);
     }
 
     return ret;
 }
 
 static inline int identical_mac_addr_allowed(int type1, int type2)
 {
     return type1 == NL80211_IFTYPE_MONITOR ||
         type2 == NL80211_IFTYPE_MONITOR ||
         type1 == NL80211_IFTYPE_P2P_DEVICE ||
         type2 == NL80211_IFTYPE_P2P_DEVICE ||
         (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
         (type1 == NL80211_IFTYPE_AP_VLAN &&
             (type2 == NL80211_IFTYPE_AP ||
              type2 == NL80211_IFTYPE_AP_VLAN));
 }
 
 static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
                         enum nl80211_iftype iftype)
 {
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_sub_if_data *nsdata;
     int ret;
 
     ASSERT_RTNL();
 
     /* we hold the RTNL here so can safely walk the list */
     list_for_each_entry(nsdata, &local->interfaces, list) {
         if (nsdata != sdata && ieee80211_sdata_running(nsdata)) {
             /*
              * Only OCB and monitor mode may coexist
              */
             if ((sdata->vif.type == NL80211_IFTYPE_OCB &&
                  nsdata->vif.type != NL80211_IFTYPE_MONITOR) ||
                 (sdata->vif.type != NL80211_IFTYPE_MONITOR &&
                  nsdata->vif.type == NL80211_IFTYPE_OCB))
                 return -EBUSY;
 
             /*
              * Allow only a single IBSS interface to be up at any
              * time. This is restricted because beacon distribution
              * cannot work properly if both are in the same IBSS.
              *
              * To remove this restriction we'd have to disallow them
              * from setting the same SSID on different IBSS interfaces
              * belonging to the same hardware. Then, however, we're
              * faced with having to adopt two different TSF timers...
              */
             if (iftype == NL80211_IFTYPE_ADHOC &&
                 nsdata->vif.type == NL80211_IFTYPE_ADHOC)
                 return -EBUSY;
             /*
              * will not add another interface while any channel
              * switch is active.
              */
             if (nsdata->vif.bss_conf.csa_active)
                 return -EBUSY;
 
             /*
              * The remaining checks are only performed for interfaces
              * with the same MAC address.
              */
             if (!ether_addr_equal(sdata->vif.addr,
                           nsdata->vif.addr))
                 continue;
 
             /*
              * check whether it may have the same address
              */
             if (!identical_mac_addr_allowed(iftype,
                             nsdata->vif.type))
                 return -ENOTUNIQ;
 
             /*
              * can only add VLANs to enabled APs
              */
             if (iftype == NL80211_IFTYPE_AP_VLAN &&
                 nsdata->vif.type == NL80211_IFTYPE_AP)
                 sdata->bss = &nsdata->u.ap;
         }
     }
 
     mutex_lock(&local->chanctx_mtx);
     ret = ieee80211_check_combinations(sdata, NULL, 0, 0);
     mutex_unlock(&local->chanctx_mtx);
     return ret;
 }
 
 static int ieee80211_check_queues(struct ieee80211_sub_if_data *sdata,
                   enum nl80211_iftype iftype)
 {
     int n_queues = sdata->local->hw.queues;
     int i;
 
     if (iftype == NL80211_IFTYPE_NAN)
         return 0;
 
     if (iftype != NL80211_IFTYPE_P2P_DEVICE) {
         for (i = 0; i < IEEE80211_NUM_ACS; i++) {
             if (WARN_ON_ONCE(sdata->vif.hw_queue[i] ==
                      IEEE80211_INVAL_HW_QUEUE))
                 return -EINVAL;
             if (WARN_ON_ONCE(sdata->vif.hw_queue[i] >=
                      n_queues))
                 return -EINVAL;
         }
     }
 
     if ((iftype != NL80211_IFTYPE_AP &&
          iftype != NL80211_IFTYPE_P2P_GO &&
          iftype != NL80211_IFTYPE_MESH_POINT) ||
         !ieee80211_hw_check(&sdata->local->hw, QUEUE_CONTROL)) {
         sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
         return 0;
     }
 
     if (WARN_ON_ONCE(sdata->vif.cab_queue == IEEE80211_INVAL_HW_QUEUE))
         return -EINVAL;
 
     if (WARN_ON_ONCE(sdata->vif.cab_queue >= n_queues))
         return -EINVAL;
 
     return 0;
 }
 
 static int ieee80211_open(struct net_device *dev)
 {
     struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
     int err;
 
     /* fail early if user set an invalid address */
     if (!is_valid_ether_addr(dev->dev_addr))
         return -EADDRNOTAVAIL;
 
     err = ieee80211_check_concurrent_iface(sdata, sdata->vif.type);
     if (err)
         return err;
 
     wiphy_lock(sdata->local->hw.wiphy);
     err = ieee80211_do_open(&sdata->wdev, true);
     wiphy_unlock(sdata->local->hw.wiphy);
 
     return err;
 }
 
 static void ieee80211_link_setup(struct ieee80211_link_data *link)
 {
     if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
         ieee80211_mgd_setup_link(link);
 }
 
 static void ieee80211_link_init(struct ieee80211_sub_if_data *sdata,
                 int link_id,
                 struct ieee80211_link_data *link,
                 struct ieee80211_bss_conf *link_conf)
 {
     bool deflink = link_id < 0;
 
     if (link_id < 0)
         link_id = 0;
 
     rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf);
     rcu_assign_pointer(sdata->link[link_id], link);
 
     link->sdata = sdata;
     link->link_id = link_id;
     link->conf = link_conf;
     link_conf->link_id = link_id;
 
     INIT_WORK(&link->csa_finalize_work,
           ieee80211_csa_finalize_work);
     INIT_WORK(&link->color_change_finalize_work,
           ieee80211_color_change_finalize_work);
     INIT_LIST_HEAD(&link->assigned_chanctx_list);
     INIT_LIST_HEAD(&link->reserved_chanctx_list);
     INIT_DELAYED_WORK(&link->dfs_cac_timer_work,
               ieee80211_dfs_cac_timer_work);
 
     if (!deflink) {
         switch (sdata->vif.type) {
         case NL80211_IFTYPE_AP:
             ether_addr_copy(link_conf->addr,
                     sdata->wdev.links[link_id].addr);
             WARN_ON(!(sdata->wdev.valid_links & BIT(link_id)));
             break;
         case NL80211_IFTYPE_STATION:
             break;
         default:
             WARN_ON(1);
         }
     }
 }
 
 static void ieee80211_link_stop(struct ieee80211_link_data *link)
 {
     if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
         ieee80211_mgd_stop_link(link);
 
     ieee80211_link_release_channel(link);
 }
 
 struct link_container {
     struct ieee80211_link_data data;
     struct ieee80211_bss_conf conf;
 };
 
 static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata,
                  struct link_container **links)
 {
     unsigned int link_id;
 
     synchronize_rcu();
 
     for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
         if (!links[link_id])
             continue;
         ieee80211_link_stop(&links[link_id]->data);
         kfree(links[link_id]);
     }
 }
 
 static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata)
 {
     unsigned int i, j;
 
     for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
         struct ieee80211_link_data *link1;
 
         link1 = sdata_dereference(sdata->link[i], sdata);
         if (!link1)
             continue;
         for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) {
             struct ieee80211_link_data *link2;
 
             link2 = sdata_dereference(sdata->link[j], sdata);
             if (!link2)
                 continue;
 
             if (ether_addr_equal(link1->conf->addr,
                          link2->conf->addr))
                 return -EALREADY;
         }
     }
 
     return 0;
 }
 
 static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata,
                       struct link_container **to_free,
                       u16 new_links)
 {
     u16 old_links = sdata->vif.valid_links;
     unsigned long add = new_links & ~old_links;
     unsigned long rem = old_links & ~new_links;
     unsigned int link_id;
     int ret;
     struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link;
     struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS];
     struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS];
     bool use_deflink = old_links == 0; /* set for error case */
 
     sdata_assert_lock(sdata);
 
     memset(to_free, 0, sizeof(links));
 
     if (old_links == new_links)
         return 0;
 
     /* if there were no old links, need to clear the pointers to deflink */
     if (!old_links)
         rem |= BIT(0);
 
     /* allocate new link structures first */
     for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
         link = kzalloc(sizeof(*link), GFP_KERNEL);
         if (!link) {
             ret = -ENOMEM;
             goto free;
         }
         links[link_id] = link;
     }
 
     /* keep track of the old pointers for the driver */
     BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf));
     memcpy(old, sdata->vif.link_conf, sizeof(old));
     /* and for us in error cases */
     BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link));
     memcpy(old_data, sdata->link, sizeof(old_data));
 
     /* grab old links to free later */
     for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
         if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) {
             /*
              * we must have allocated the data through this path so
              * we know we can free both at the same time
              */
             to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]),
                             typeof(*links[link_id]),
                             data);
         }
 
         RCU_INIT_POINTER(sdata->link[link_id], NULL);
         RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL);
     }
 
     /* link them into data structures */
     for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
         WARN_ON(!use_deflink &&
             rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink);
 
         link = links[link_id];
         ieee80211_link_init(sdata, link_id, &link->data, &link->conf);
         ieee80211_link_setup(&link->data);
     }
 
     if (new_links == 0)
         ieee80211_link_init(sdata, -1, &sdata->deflink,
                     &sdata->vif.bss_conf);
 
     sdata->vif.valid_links = new_links;
 
     ret = ieee80211_check_dup_link_addrs(sdata);
     if (!ret) {
         /* tell the driver */
         ret = drv_change_vif_links(sdata->local, sdata,
                        old_links, new_links,
                        old);
     }
 
     if (ret) {
         /* restore config */
         memcpy(sdata->link, old_data, sizeof(old_data));
         memcpy(sdata->vif.link_conf, old, sizeof(old));
         sdata->vif.valid_links = old_links;
         /* and free (only) the newly allocated links */
         memset(to_free, 0, sizeof(links));
         goto free;
     }
 
     /* use deflink/bss_conf again if and only if there are no more links */
     use_deflink = new_links == 0;
 
     goto deinit;
 free:
     /* if we failed during allocation, only free all */
     for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
         kfree(links[link_id]);
         links[link_id] = NULL;
     }
 deinit:
     if (use_deflink)
         ieee80211_link_init(sdata, -1, &sdata->deflink,
                     &sdata->vif.bss_conf);
     return ret;
 }
 
 int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata,
                 u16 new_links)
 {
     struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
     int ret;
 
     ret = ieee80211_vif_update_links(sdata, links, new_links);
     ieee80211_free_links(sdata, links);
 
     return ret;
 }
 
 static void ieee80211_vif_clear_links(struct ieee80211_sub_if_data *sdata)
 {
     struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
 
     /*
      * The locking here is different because when we free links
      * in the station case we need to be able to cancel_work_sync()
      * something that also takes the lock.
      */
 
     sdata_lock(sdata);
     ieee80211_vif_update_links(sdata, links, 0);
     sdata_unlock(sdata);
 
     ieee80211_free_links(sdata, links);
 }
 
 static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata, bool going_down)
 {
     struct ieee80211_local *local = sdata->local;
     unsigned long flags;
     struct sk_buff *skb, *tmp;
     u32 hw_reconf_flags = 0;
     int i, flushed;
     struct ps_data *ps;
     struct cfg80211_chan_def chandef;
     bool cancel_scan;
     struct cfg80211_nan_func *func;
 
     clear_bit(SDATA_STATE_RUNNING, &sdata->state);
     synchronize_rcu(); /* flush _ieee80211_wake_txqs() */
 
     cancel_scan = rcu_access_pointer(local->scan_sdata) == sdata;
     if (cancel_scan)
         ieee80211_scan_cancel(local);
 
     /*
      * Stop TX on this interface first.
      */
     if (sdata->dev)
         netif_tx_stop_all_queues(sdata->dev);
 
     ieee80211_roc_purge(local, sdata);
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_STATION:
         ieee80211_mgd_stop(sdata);
         break;
     case NL80211_IFTYPE_ADHOC:
         ieee80211_ibss_stop(sdata);
         break;
     case NL80211_IFTYPE_MONITOR:
         if (sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES)
             break;
         list_del_rcu(&sdata->u.mntr.list);
         break;
     default:
         break;
     }
 
     /*
      * Remove all stations associated with this interface.
      *
      * This must be done before calling ops->remove_interface()
      * because otherwise we can later invoke ops->sta_notify()
      * whenever the STAs are removed, and that invalidates driver
      * assumptions about always getting a vif pointer that is valid
      * (because if we remove a STA after ops->remove_interface()
      * the driver will have removed the vif info already!)
      *
      * For AP_VLANs stations may exist since there's nothing else that
      * would have removed them, but in other modes there shouldn't
      * be any stations.
      */
     flushed = sta_info_flush(sdata);
     WARN_ON_ONCE(sdata->vif.type != NL80211_IFTYPE_AP_VLAN && flushed > 0);
 
     /* don't count this interface for allmulti while it is down */
     if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
         atomic_dec(&local->iff_allmultis);
 
     if (sdata->vif.type == NL80211_IFTYPE_AP) {
         local->fif_pspoll--;
         local->fif_probe_req--;
     } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
         local->fif_probe_req--;
     }
 
     if (sdata->dev) {
         netif_addr_lock_bh(sdata->dev);
         spin_lock_bh(&local->filter_lock);
         __hw_addr_unsync(&local->mc_list, &sdata->dev->mc,
                  sdata->dev->addr_len);
         spin_unlock_bh(&local->filter_lock);
         netif_addr_unlock_bh(sdata->dev);
     }
 
     del_timer_sync(&local->dynamic_ps_timer);
     cancel_work_sync(&local->dynamic_ps_enable_work);
 
     cancel_work_sync(&sdata->recalc_smps);
 
     sdata_lock(sdata);
     WARN(sdata->vif.valid_links,
          "destroying interface with valid links 0x%04x\n",
          sdata->vif.valid_links);
 
     mutex_lock(&local->mtx);
     sdata->vif.bss_conf.csa_active = false;
     if (sdata->vif.type == NL80211_IFTYPE_STATION)
         sdata->deflink.u.mgd.csa_waiting_bcn = false;
     if (sdata->deflink.csa_block_tx) {
         ieee80211_wake_vif_queues(local, sdata,
                       IEEE80211_QUEUE_STOP_REASON_CSA);
         sdata->deflink.csa_block_tx = false;
     }
     mutex_unlock(&local->mtx);
     sdata_unlock(sdata);
 
     cancel_work_sync(&sdata->deflink.csa_finalize_work);
     cancel_work_sync(&sdata->deflink.color_change_finalize_work);
 
     cancel_delayed_work_sync(&sdata->deflink.dfs_cac_timer_work);
 
     if (sdata->wdev.cac_started) {
         chandef = sdata->vif.bss_conf.chandef;
         WARN_ON(local->suspended);
         mutex_lock(&local->mtx);
         ieee80211_link_release_channel(&sdata->deflink);
         mutex_unlock(&local->mtx);
         cfg80211_cac_event(sdata->dev, &chandef,
                    NL80211_RADAR_CAC_ABORTED,
                    GFP_KERNEL);
     }
 
     if (sdata->vif.type == NL80211_IFTYPE_AP) {
         WARN_ON(!list_empty(&sdata->u.ap.vlans));
     } else if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
         /* remove all packets in parent bc_buf pointing to this dev */
         ps = &sdata->bss->ps;
 
         spin_lock_irqsave(&ps->bc_buf.lock, flags);
         skb_queue_walk_safe(&ps->bc_buf, skb, tmp) {
             if (skb->dev == sdata->dev) {
                 __skb_unlink(skb, &ps->bc_buf);
                 local->total_ps_buffered--;
                 ieee80211_free_txskb(&local->hw, skb);
             }
         }
         spin_unlock_irqrestore(&ps->bc_buf.lock, flags);
     }
 
     if (going_down)
         local->open_count--;
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_AP_VLAN:
         mutex_lock(&local->mtx);
         list_del(&sdata->u.vlan.list);
         mutex_unlock(&local->mtx);
         RCU_INIT_POINTER(sdata->vif.bss_conf.chanctx_conf, NULL);
         /* see comment in the default case below */
         ieee80211_free_keys(sdata, true);
         /* no need to tell driver */
         break;
     case NL80211_IFTYPE_MONITOR:
         if (sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES) {
             local->cooked_mntrs--;
             break;
         }
 
         local->monitors--;
         if (local->monitors == 0) {
             local->hw.conf.flags &= ~IEEE80211_CONF_MONITOR;
             hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
         }
 
         ieee80211_adjust_monitor_flags(sdata, -1);
         break;
     case NL80211_IFTYPE_NAN:
         /* clean all the functions */
         spin_lock_bh(&sdata->u.nan.func_lock);
 
         idr_for_each_entry(&sdata->u.nan.function_inst_ids, func, i) {
             idr_remove(&sdata->u.nan.function_inst_ids, i);
             cfg80211_free_nan_func(func);
         }
         idr_destroy(&sdata->u.nan.function_inst_ids);
 
         spin_unlock_bh(&sdata->u.nan.func_lock);
         break;
     case NL80211_IFTYPE_P2P_DEVICE:
         /* relies on synchronize_rcu() below */
         RCU_INIT_POINTER(local->p2p_sdata, NULL);
         fallthrough;
     default:
         cancel_work_sync(&sdata->work);
         /*
          * When we get here, the interface is marked down.
          * Free the remaining keys, if there are any
          * (which can happen in AP mode if userspace sets
          * keys before the interface is operating)
          *
          * Force the key freeing to always synchronize_net()
          * to wait for the RX path in case it is using this
          * interface enqueuing frames at this very time on
          * another CPU.
          */
         ieee80211_free_keys(sdata, true);
         skb_queue_purge(&sdata->skb_queue);
         skb_queue_purge(&sdata->status_queue);
     }
 
     spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
     for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
         skb_queue_walk_safe(&local->pending[i], skb, tmp) {
             struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
             if (info->control.vif == &sdata->vif) {
                 __skb_unlink(skb, &local->pending[i]);
                 ieee80211_free_txskb(&local->hw, skb);
             }
         }
     }
     spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 
     if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
         ieee80211_txq_remove_vlan(local, sdata);
 
     sdata->bss = NULL;
 
     if (local->open_count == 0)
         ieee80211_clear_tx_pending(local);
 
     sdata->vif.bss_conf.beacon_int = 0;
 
     /*
      * If the interface goes down while suspended, presumably because
      * the device was unplugged and that happens before our resume,
      * then the driver is already unconfigured and the remainder of
      * this function isn't needed.
      * XXX: what about WoWLAN? If the device has software state, e.g.
      *  memory allocated, it might expect teardown commands from
      *  mac80211 here?
      */
     if (local->suspended) {
         WARN_ON(local->wowlan);
         WARN_ON(rcu_access_pointer(local->monitor_sdata));
         return;
     }
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_AP_VLAN:
         break;
     case NL80211_IFTYPE_MONITOR:
         if (local->monitors == 0)
             ieee80211_del_virtual_monitor(local);
 
         mutex_lock(&local->mtx);
         ieee80211_recalc_idle(local);
         mutex_unlock(&local->mtx);
 
         if (!(sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE))
             break;
 
         fallthrough;
     default:
         if (going_down)
             drv_remove_interface(local, sdata);
     }
 
     ieee80211_recalc_ps(local);
 
     if (cancel_scan)
         flush_delayed_work(&local->scan_work);
 
     if (local->open_count == 0) {
         ieee80211_stop_device(local);
 
         /* no reconfiguring after stop! */
         return;
     }
 
     /* do after stop to avoid reconfiguring when we stop anyway */
     ieee80211_configure_filter(local);
     ieee80211_hw_config(local, hw_reconf_flags);
 
     if (local->monitors == local->open_count)
         ieee80211_add_virtual_monitor(local);
 }
 
 static void ieee80211_stop_mbssid(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_sub_if_data *tx_sdata, *non_tx_sdata, *tmp_sdata;
     struct ieee80211_vif *tx_vif = sdata->vif.mbssid_tx_vif;
 
     if (!tx_vif)
         return;
 
     tx_sdata = vif_to_sdata(tx_vif);
     sdata->vif.mbssid_tx_vif = NULL;
 
     list_for_each_entry_safe(non_tx_sdata, tmp_sdata,
                  &tx_sdata->local->interfaces, list) {
         if (non_tx_sdata != sdata && non_tx_sdata != tx_sdata &&
             non_tx_sdata->vif.mbssid_tx_vif == tx_vif &&
             ieee80211_sdata_running(non_tx_sdata)) {
             non_tx_sdata->vif.mbssid_tx_vif = NULL;
             dev_close(non_tx_sdata->wdev.netdev);
         }
     }
 
     if (sdata != tx_sdata && ieee80211_sdata_running(tx_sdata)) {
         tx_sdata->vif.mbssid_tx_vif = NULL;
         dev_close(tx_sdata->wdev.netdev);
     }
 }
 
 static int ieee80211_stop(struct net_device *dev)
 {
     struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
     /* close dependent VLAN and MBSSID interfaces before locking wiphy */
     if (sdata->vif.type == NL80211_IFTYPE_AP) {
         struct ieee80211_sub_if_data *vlan, *tmpsdata;
 
         list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
                      u.vlan.list)
             dev_close(vlan->dev);
 
         ieee80211_stop_mbssid(sdata);
     }
 
     wiphy_lock(sdata->local->hw.wiphy);
     ieee80211_do_stop(sdata, true);
     wiphy_unlock(sdata->local->hw.wiphy);
 
     return 0;
 }
 
 static void ieee80211_set_multicast_list(struct net_device *dev)
 {
     struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
     struct ieee80211_local *local = sdata->local;
     int allmulti, sdata_allmulti;
 
     allmulti = !!(dev->flags & IFF_ALLMULTI);
     sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
 
     if (allmulti != sdata_allmulti) {
         if (dev->flags & IFF_ALLMULTI)
             atomic_inc(&local->iff_allmultis);
         else
             atomic_dec(&local->iff_allmultis);
         sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
     }
 
     spin_lock_bh(&local->filter_lock);
     __hw_addr_sync(&local->mc_list, &dev->mc, dev->addr_len);
     spin_unlock_bh(&local->filter_lock);
     ieee80211_queue_work(&local->hw, &local->reconfig_filter);
 }
 
 /*
  * Called when the netdev is removed or, by the code below, before
  * the interface type changes.
  */
 static void ieee80211_teardown_sdata(struct ieee80211_sub_if_data *sdata)
 {
     /* free extra data */
     ieee80211_free_keys(sdata, false);
 
     ieee80211_debugfs_remove_netdev(sdata);
 
     ieee80211_destroy_frag_cache(&sdata->frags);
 
     if (ieee80211_vif_is_mesh(&sdata->vif))
         ieee80211_mesh_teardown_sdata(sdata);
 
     ieee80211_vif_clear_links(sdata);
     ieee80211_link_stop(&sdata->deflink);
 }
 
 static void ieee80211_uninit(struct net_device *dev)
 {
     ieee80211_teardown_sdata(IEEE80211_DEV_TO_SUB_IF(dev));
 }
 
 static u16 ieee80211_netdev_select_queue(struct net_device *dev,
                      struct sk_buff *skb,
                      struct net_device *sb_dev)
 {
     return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb);
 }
 
 static void
 ieee80211_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
 {
     dev_fetch_sw_netstats(stats, dev->tstats);
 }
 
 static const struct net_device_ops ieee80211_dataif_ops = {
     .ndo_open       = ieee80211_open,
     .ndo_stop       = ieee80211_stop,
     .ndo_uninit     = ieee80211_uninit,
     .ndo_start_xmit     = ieee80211_subif_start_xmit,
     .ndo_set_rx_mode    = ieee80211_set_multicast_list,
     .ndo_set_mac_address    = ieee80211_change_mac,
     .ndo_select_queue   = ieee80211_netdev_select_queue,
     .ndo_get_stats64    = ieee80211_get_stats64,
 };
 
 static u16 ieee80211_monitor_select_queue(struct net_device *dev,
                       struct sk_buff *skb,
                       struct net_device *sb_dev)
 {
     struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
     struct ieee80211_hdr *hdr;
     int len_rthdr;
 
     if (local->hw.queues < IEEE80211_NUM_ACS)
         return 0;
 
     /* reset flags and info before parsing radiotap header */
     memset(info, 0, sizeof(*info));
 
     if (!ieee80211_parse_tx_radiotap(skb, dev))
         return 0; /* doesn't matter, frame will be dropped */
 
     len_rthdr = ieee80211_get_radiotap_len(skb->data);
     hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
     if (skb->len < len_rthdr + 2 ||
         skb->len < len_rthdr + ieee80211_hdrlen(hdr->frame_control))
         return 0; /* doesn't matter, frame will be dropped */
 
     return ieee80211_select_queue_80211(sdata, skb, hdr);
 }
 
 static const struct net_device_ops ieee80211_monitorif_ops = {
     .ndo_open       = ieee80211_open,
     .ndo_stop       = ieee80211_stop,
     .ndo_uninit     = ieee80211_uninit,
     .ndo_start_xmit     = ieee80211_monitor_start_xmit,
     .ndo_set_rx_mode    = ieee80211_set_multicast_list,
     .ndo_set_mac_address    = ieee80211_change_mac,
     .ndo_select_queue   = ieee80211_monitor_select_queue,
     .ndo_get_stats64    = ieee80211_get_stats64,
 };
 
 static int ieee80211_netdev_fill_forward_path(struct net_device_path_ctx *ctx,
                           struct net_device_path *path)
 {
     struct ieee80211_sub_if_data *sdata;
     struct ieee80211_local *local;
     struct sta_info *sta;
     int ret = -ENOENT;
 
     sdata = IEEE80211_DEV_TO_SUB_IF(ctx->dev);
     local = sdata->local;
 
     if (!local->ops->net_fill_forward_path)
         return -EOPNOTSUPP;
 
     rcu_read_lock();
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_AP_VLAN:
         sta = rcu_dereference(sdata->u.vlan.sta);
         if (sta)
             break;
         if (sdata->wdev.use_4addr)
             goto out;
         if (is_multicast_ether_addr(ctx->daddr))
             goto out;
         sta = sta_info_get_bss(sdata, ctx->daddr);
         break;
     case NL80211_IFTYPE_AP:
         if (is_multicast_ether_addr(ctx->daddr))
             goto out;
         sta = sta_info_get(sdata, ctx->daddr);
         break;
     case NL80211_IFTYPE_STATION:
         if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
             sta = sta_info_get(sdata, ctx->daddr);
             if (sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER)) {
                 if (!test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
                     goto out;
 
                 break;
             }
         }
 
         sta = sta_info_get(sdata, sdata->deflink.u.mgd.bssid);
         break;
     default:
         goto out;
     }
 
     if (!sta)
         goto out;
 
     ret = drv_net_fill_forward_path(local, sdata, &sta->sta, ctx, path);
 out:
     rcu_read_unlock();
 
     return ret;
 }
 
 static const struct net_device_ops ieee80211_dataif_8023_ops = {
     .ndo_open       = ieee80211_open,
     .ndo_stop       = ieee80211_stop,
     .ndo_uninit     = ieee80211_uninit,
     .ndo_start_xmit     = ieee80211_subif_start_xmit_8023,
     .ndo_set_rx_mode    = ieee80211_set_multicast_list,
     .ndo_set_mac_address    = ieee80211_change_mac,
     .ndo_select_queue   = ieee80211_netdev_select_queue,
     .ndo_get_stats64    = ieee80211_get_stats64,
     .ndo_fill_forward_path  = ieee80211_netdev_fill_forward_path,
 };
 
 static bool ieee80211_iftype_supports_hdr_offload(enum nl80211_iftype iftype)
 {
     switch (iftype) {
     /* P2P GO and client are mapped to AP/STATION types */
     case NL80211_IFTYPE_AP:
     case NL80211_IFTYPE_STATION:
         return true;
     default:
         return false;
     }
 }
 
 static bool ieee80211_set_sdata_offload_flags(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_local *local = sdata->local;
     u32 flags;
 
     flags = sdata->vif.offload_flags;
 
     if (ieee80211_hw_check(&local->hw, SUPPORTS_TX_ENCAP_OFFLOAD) &&
         ieee80211_iftype_supports_hdr_offload(sdata->vif.type)) {
         flags |= IEEE80211_OFFLOAD_ENCAP_ENABLED;
 
         if (!ieee80211_hw_check(&local->hw, SUPPORTS_TX_FRAG) &&
             local->hw.wiphy->frag_threshold != (u32)-1)
             flags &= ~IEEE80211_OFFLOAD_ENCAP_ENABLED;
 
         if (local->monitors)
             flags &= ~IEEE80211_OFFLOAD_ENCAP_ENABLED;
     } else {
         flags &= ~IEEE80211_OFFLOAD_ENCAP_ENABLED;
     }
 
     if (ieee80211_hw_check(&local->hw, SUPPORTS_RX_DECAP_OFFLOAD) &&
         ieee80211_iftype_supports_hdr_offload(sdata->vif.type)) {
         flags |= IEEE80211_OFFLOAD_DECAP_ENABLED;
 
         if (local->monitors &&
             !ieee80211_hw_check(&local->hw, SUPPORTS_CONC_MON_RX_DECAP))
             flags &= ~IEEE80211_OFFLOAD_DECAP_ENABLED;
     } else {
         flags &= ~IEEE80211_OFFLOAD_DECAP_ENABLED;
     }
 
     if (sdata->vif.offload_flags == flags)
         return false;
 
     sdata->vif.offload_flags = flags;
     ieee80211_check_fast_rx_iface(sdata);
     return true;
 }
 
 static void ieee80211_set_vif_encap_ops(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_sub_if_data *bss = sdata;
     bool enabled;
 
     if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
         if (!sdata->bss)
             return;
 
         bss = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
     }
 
     if (!ieee80211_hw_check(&local->hw, SUPPORTS_TX_ENCAP_OFFLOAD) ||
         !ieee80211_iftype_supports_hdr_offload(bss->vif.type))
         return;
 
     enabled = bss->vif.offload_flags & IEEE80211_OFFLOAD_ENCAP_ENABLED;
     if (sdata->wdev.use_4addr &&
         !(bss->vif.offload_flags & IEEE80211_OFFLOAD_ENCAP_4ADDR))
         enabled = false;
 
     sdata->dev->netdev_ops = enabled ? &ieee80211_dataif_8023_ops :
                        &ieee80211_dataif_ops;
 }
 
 static void ieee80211_recalc_sdata_offload(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_local *local = sdata->local;
     struct ieee80211_sub_if_data *vsdata;
 
     if (ieee80211_set_sdata_offload_flags(sdata)) {
         drv_update_vif_offload(local, sdata);
         ieee80211_set_vif_encap_ops(sdata);
     }
 
     list_for_each_entry(vsdata, &local->interfaces, list) {
         if (vsdata->vif.type != NL80211_IFTYPE_AP_VLAN ||
             vsdata->bss != &sdata->u.ap)
             continue;
 
         ieee80211_set_vif_encap_ops(vsdata);
     }
 }
 
 void ieee80211_recalc_offload(struct ieee80211_local *local)
 {
     struct ieee80211_sub_if_data *sdata;
 
     if (!ieee80211_hw_check(&local->hw, SUPPORTS_TX_ENCAP_OFFLOAD))
         return;
 
     mutex_lock(&local->iflist_mtx);
 
     list_for_each_entry(sdata, &local->interfaces, list) {
         if (!ieee80211_sdata_running(sdata))
             continue;
 
         ieee80211_recalc_sdata_offload(sdata);
     }
 
     mutex_unlock(&local->iflist_mtx);
 }
 
 void ieee80211_adjust_monitor_flags(struct ieee80211_sub_if_data *sdata,
                     const int offset)
 {
     struct ieee80211_local *local = sdata->local;
     u32 flags = sdata->u.mntr.flags;
 
 #define ADJUST(_f, _s)  do {                    \
     if (flags & MONITOR_FLAG_##_f)              \
         local->fif_##_s += offset;          \
     } while (0)
 
     ADJUST(FCSFAIL, fcsfail);
     ADJUST(PLCPFAIL, plcpfail);
     ADJUST(CONTROL, control);
     ADJUST(CONTROL, pspoll);
     ADJUST(OTHER_BSS, other_bss);
 
 #undef ADJUST
 }
 
 static void ieee80211_set_default_queues(struct ieee80211_sub_if_data *sdata)
 {
     struct ieee80211_local *local = sdata->local;
     int i;
 
     for (i = 0; i < IEEE80211_NUM_ACS; i++) {
         if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
             sdata->vif.hw_queue[i] = IEEE80211_INVAL_HW_QUEUE;
         else if (local->hw.queues >= IEEE80211_NUM_ACS)
             sdata->vif.hw_queue[i] = i;
         else
             sdata->vif.hw_queue[i] = 0;
     }
     sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
 }
 
 static void ieee80211_sdata_init(struct ieee80211_local *local,
                  struct ieee80211_sub_if_data *sdata)
 {
     sdata->local = local;
 
     /*
      * Initialize the default link, so we can use link_id 0 for non-MLD,
      * and that continues to work for non-MLD-aware drivers that use just
      * vif.bss_conf instead of vif.link_conf.
      *
      * Note that we never change this, so if link ID 0 isn't used in an
      * MLD connection, we get a separate allocation for it.
      */
     ieee80211_link_init(sdata, -1, &sdata->deflink, &sdata->vif.bss_conf);
 }
 
 int ieee80211_add_virtual_monitor(struct ieee80211_local *local)
 {
     struct ieee80211_sub_if_data *sdata;
     int ret;
 
     if (!ieee80211_hw_check(&local->hw, WANT_MONITOR_VIF))
         return 0;
 
     ASSERT_RTNL();
     lockdep_assert_wiphy(local->hw.wiphy);
 
     if (local->monitor_sdata)
         return 0;
 
     sdata = kzalloc(sizeof(*sdata) + local->hw.vif_data_size, GFP_KERNEL);
     if (!sdata)
         return -ENOMEM;
 
     /* set up data */
     sdata->vif.type = NL80211_IFTYPE_MONITOR;
     snprintf(sdata->name, IFNAMSIZ, "%s-monitor",
          wiphy_name(local->hw.wiphy));
     sdata->wdev.iftype = NL80211_IFTYPE_MONITOR;
 
     ieee80211_sdata_init(local, sdata);
 
     ieee80211_set_default_queues(sdata);
 
     ret = drv_add_interface(local, sdata);
     if (WARN_ON(ret)) {
         /* ok .. stupid driver, it asked for this! */
         kfree(sdata);
         return ret;
     }
 
     set_bit(SDATA_STATE_RUNNING, &sdata->state);
 
     ret = ieee80211_check_queues(sdata, NL80211_IFTYPE_MONITOR);
     if (ret) {
         kfree(sdata);
         return ret;
     }
 
     mutex_lock(&local->iflist_mtx);
     rcu_assign_pointer(local->monitor_sdata, sdata);
     mutex_unlock(&local->iflist_mtx);
 
     mutex_lock(&local->mtx);
     ret = ieee80211_link_use_channel(&sdata->deflink, &local->monitor_chandef,
                      IEEE80211_CHANCTX_EXCLUSIVE);
     mutex_unlock(&local->mtx);
     if (ret) {
         mutex_lock(&local->iflist_mtx);
         RCU_INIT_POINTER(local->monitor_sdata, NULL);
         mutex_unlock(&local->iflist_mtx);
         synchronize_net();
         drv_remove_interface(local, sdata);
         kfree(sdata);
         return ret;
     }
 
     skb_queue_head_init(&sdata->skb_queue);
     skb_queue_head_init(&sdata->status_queue);
     INIT_WORK(&sdata->work, ieee80211_iface_work);
 
     return 0;
 }
 
 void ieee80211_del_virtual_monitor(struct ieee80211_local *local)
 {
     struct ieee80211_sub_if_data *sdata;
 
     if (!ieee80211_hw_check(&local->hw, WANT_MONITOR_VIF))
         return;
 
     ASSERT_RTNL();
     lockdep_assert_wiphy(local->hw.wiphy);
 
     mutex_lock(&local->iflist_mtx);
 
     sdata = rcu_dereference_protected(local->monitor_sdata,
                       lockdep_is_held(&local->iflist_mtx));
     if (!sdata) {
         mutex_unlock(&local->iflist_mtx);
         return;
     }
 
     RCU_INIT_POINTER(local->monitor_sdata, NULL);
     mutex_unlock(&local->iflist_mtx);
 
     synchronize_net();
 
     mutex_lock(&local->mtx);
     ieee80211_link_release_channel(&sdata->deflink);
     mutex_unlock(&local->mtx);
 
     drv_remove_interface(local, sdata);
 
     kfree(sdata);
 }
 
 /*
  * NOTE: Be very careful when changing this function, it must NOT return
  * an error on interface type changes that have been pre-checked, so most
  * checks should be in ieee80211_check_concurrent_iface.
  */
 int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
 {
     struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
     struct net_device *dev = wdev->netdev;
     struct ieee80211_local *local = sdata->local;
     u32 changed = 0;
     int res;
     u32 hw_reconf_flags = 0;
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_AP_VLAN: {
         struct ieee80211_sub_if_data *master;
 
         if (!sdata->bss)
             return -ENOLINK;
 
         mutex_lock(&local->mtx);
         list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
         mutex_unlock(&local->mtx);
 
         master = container_of(sdata->bss,
                       struct ieee80211_sub_if_data, u.ap);
         sdata->control_port_protocol =
             master->control_port_protocol;
         sdata->control_port_no_encrypt =
             master->control_port_no_encrypt;
         sdata->control_port_over_nl80211 =
             master->control_port_over_nl80211;
         sdata->control_port_no_preauth =
             master->control_port_no_preauth;
         sdata->vif.cab_queue = master->vif.cab_queue;
         memcpy(sdata->vif.hw_queue, master->vif.hw_queue,
                sizeof(sdata->vif.hw_queue));
         sdata->vif.bss_conf.chandef = master->vif.bss_conf.chandef;
 
         mutex_lock(&local->key_mtx);
         sdata->crypto_tx_tailroom_needed_cnt +=
             master->crypto_tx_tailroom_needed_cnt;
         mutex_unlock(&local->key_mtx);
 
         break;
         }
     case NL80211_IFTYPE_AP:
         sdata->bss = &sdata->u.ap;
         break;
     case NL80211_IFTYPE_MESH_POINT:
     case NL80211_IFTYPE_STATION:
     case NL80211_IFTYPE_MONITOR:
     case NL80211_IFTYPE_ADHOC:
     case NL80211_IFTYPE_P2P_DEVICE:
     case NL80211_IFTYPE_OCB:
     case NL80211_IFTYPE_NAN:
         /* no special treatment */
         break;
     case NL80211_IFTYPE_UNSPECIFIED:
     case NUM_NL80211_IFTYPES:
     case NL80211_IFTYPE_P2P_CLIENT:
     case NL80211_IFTYPE_P2P_GO:
     case NL80211_IFTYPE_WDS:
         /* cannot happen */
         WARN_ON(1);
         break;
     }
 
     if (local->open_count == 0) {
         res = drv_start(local);
         if (res)
             goto err_del_bss;
         /* we're brought up, everything changes */
         hw_reconf_flags = ~0;
         ieee80211_led_radio(local, true);
         ieee80211_mod_tpt_led_trig(local,
                        IEEE80211_TPT_LEDTRIG_FL_RADIO, 0);
     }
 
     /*
      * Copy the hopefully now-present MAC address to
      * this interface, if it has the special null one.
      */
     if (dev && is_zero_ether_addr(dev->dev_addr)) {
         eth_hw_addr_set(dev, local->hw.wiphy->perm_addr);
         memcpy(dev->perm_addr, dev->dev_addr, ETH_ALEN);
 
         if (!is_valid_ether_addr(dev->dev_addr)) {
             res = -EADDRNOTAVAIL;
             goto err_stop;
         }
     }
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_AP_VLAN:
         /* no need to tell driver, but set carrier and chanctx */
         if (sdata->bss->active) {
             ieee80211_link_vlan_copy_chanctx(&sdata->deflink);
             netif_carrier_on(dev);
             ieee80211_set_vif_encap_ops(sdata);
         } else {
             netif_carrier_off(dev);
         }
         break;
     case NL80211_IFTYPE_MONITOR:
         if (sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES) {
             local->cooked_mntrs++;
             break;
         }
 
         if (sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE) {
             res = drv_add_interface(local, sdata);
             if (res)
                 goto err_stop;
         } else if (local->monitors == 0 && local->open_count == 0) {
             res = ieee80211_add_virtual_monitor(local);
             if (res)
                 goto err_stop;
         }
 
         /* must be before the call to ieee80211_configure_filter */
         local->monitors++;
         if (local->monitors == 1) {
             local->hw.conf.flags |= IEEE80211_CONF_MONITOR;
             hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
         }
 
         ieee80211_adjust_monitor_flags(sdata, 1);
         ieee80211_configure_filter(local);
         ieee80211_recalc_offload(local);
         mutex_lock(&local->mtx);
         ieee80211_recalc_idle(local);
         mutex_unlock(&local->mtx);
 
         netif_carrier_on(dev);
         break;
     default:
         if (coming_up) {
             ieee80211_del_virtual_monitor(local);
             ieee80211_set_sdata_offload_flags(sdata);
 
             res = drv_add_interface(local, sdata);
             if (res)
                 goto err_stop;
 
             ieee80211_set_vif_encap_ops(sdata);
             res = ieee80211_check_queues(sdata,
                 ieee80211_vif_type_p2p(&sdata->vif));
             if (res)
                 goto err_del_interface;
         }
 
         if (sdata->vif.type == NL80211_IFTYPE_AP) {
             local->fif_pspoll++;
             local->fif_probe_req++;
 
             ieee80211_configure_filter(local);
         } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
             local->fif_probe_req++;
         }
 
         if (sdata->vif.probe_req_reg)
             drv_config_iface_filter(local, sdata,
                         FIF_PROBE_REQ,
                         FIF_PROBE_REQ);
 
         if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
             sdata->vif.type != NL80211_IFTYPE_NAN)
             changed |= ieee80211_reset_erp_info(sdata);
         ieee80211_link_info_change_notify(sdata, &sdata->deflink,
                           changed);
 
         switch (sdata->vif.type) {
         case NL80211_IFTYPE_STATION:
         case NL80211_IFTYPE_ADHOC:
         case NL80211_IFTYPE_AP:
         case NL80211_IFTYPE_MESH_POINT:
         case NL80211_IFTYPE_OCB:
             netif_carrier_off(dev);
             break;
         case NL80211_IFTYPE_P2P_DEVICE:
         case NL80211_IFTYPE_NAN:
             break;
         default:
             /* not reached */
             WARN_ON(1);
         }
 
         /*
          * Set default queue parameters so drivers don't
          * need to initialise the hardware if the hardware
          * doesn't start up with sane defaults.
          * Enable QoS for anything but station interfaces.
          */
         ieee80211_set_wmm_default(&sdata->deflink, true,
             sdata->vif.type != NL80211_IFTYPE_STATION);
     }
 
     set_bit(SDATA_STATE_RUNNING, &sdata->state);
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_P2P_DEVICE:
         rcu_assign_pointer(local->p2p_sdata, sdata);
         break;
     case NL80211_IFTYPE_MONITOR:
         if (sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES)
             break;
         list_add_tail_rcu(&sdata->u.mntr.list, &local->mon_list);
         break;
     default:
         break;
     }
 
     /*
      * set_multicast_list will be invoked by the networking core
      * which will check whether any increments here were done in
      * error and sync them down to the hardware as filter flags.
      */
     if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
         atomic_inc(&local->iff_allmultis);
 
     if (coming_up)
         local->open_count++;
 
     if (hw_reconf_flags)
         ieee80211_hw_config(local, hw_reconf_flags);
 
     ieee80211_recalc_ps(local);
 
     if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
         sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
         local->ops->wake_tx_queue) {
         /* XXX: for AP_VLAN, actually track AP queues */
         if (dev)
             netif_tx_start_all_queues(dev);
     } else if (dev) {
         unsigned long flags;
         int n_acs = IEEE80211_NUM_ACS;
         int ac;
 
         if (local->hw.queues < IEEE80211_NUM_ACS)
             n_acs = 1;
 
         spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
         if (sdata->vif.cab_queue == IEEE80211_INVAL_HW_QUEUE ||
             (local->queue_stop_reasons[sdata->vif.cab_queue] == 0 &&
              skb_queue_empty(&local->pending[sdata->vif.cab_queue]))) {
             for (ac = 0; ac < n_acs; ac++) {
                 int ac_queue = sdata->vif.hw_queue[ac];
 
                 if (local->queue_stop_reasons[ac_queue] == 0 &&
                     skb_queue_empty(&local->pending[ac_queue]))
                     netif_start_subqueue(dev, ac);
             }
         }
         spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
     }
 
     return 0;
  err_del_interface:
     drv_remove_interface(local, sdata);
  err_stop:
     if (!local->open_count)
         drv_stop(local);
  err_del_bss:
     sdata->bss = NULL;
     if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
         mutex_lock(&local->mtx);
         list_del(&sdata->u.vlan.list);
         mutex_unlock(&local->mtx);
     }
     /* might already be clear but that doesn't matter */
     clear_bit(SDATA_STATE_RUNNING, &sdata->state);
     return res;
 }
 
 static void ieee80211_if_free(struct net_device *dev)
 {
     free_percpu(dev->tstats);
 }
 
 static void ieee80211_if_setup(struct net_device *dev)
 {
     ether_setup(dev);
     dev->priv_flags &= ~IFF_TX_SKB_SHARING;
     dev->netdev_ops = &ieee80211_dataif_ops;
     dev->needs_free_netdev = true;
     dev->priv_destructor = ieee80211_if_free;
 }
 
 static void ieee80211_if_setup_no_queue(struct net_device *dev)
 {
     ieee80211_if_setup(dev);
     dev->priv_flags |= IFF_NO_QUEUE;
 }
 
 static void ieee80211_iface_process_skb(struct ieee80211_local *local,
                     struct ieee80211_sub_if_data *sdata,
                     struct sk_buff *skb)
 {
     struct ieee80211_mgmt *mgmt = (void *)skb->data;
 
     if (ieee80211_is_action(mgmt->frame_control) &&
         mgmt->u.action.category == WLAN_CATEGORY_BACK) {
         struct sta_info *sta;
         int len = skb->len;
 
         mutex_lock(&local->sta_mtx);
         sta = sta_info_get_bss(sdata, mgmt->sa);
         if (sta) {
             switch (mgmt->u.action.u.addba_req.action_code) {
             case WLAN_ACTION_ADDBA_REQ:
                 ieee80211_process_addba_request(local, sta,
                                 mgmt, len);
                 break;
             case WLAN_ACTION_ADDBA_RESP:
                 ieee80211_process_addba_resp(local, sta,
                                  mgmt, len);
                 break;
             case WLAN_ACTION_DELBA:
                 ieee80211_process_delba(sdata, sta,
                             mgmt, len);
                 break;
             default:
                 WARN_ON(1);
                 break;
             }
         }
         mutex_unlock(&local->sta_mtx);
     } else if (ieee80211_is_action(mgmt->frame_control) &&
            mgmt->u.action.category == WLAN_CATEGORY_VHT) {
         switch (mgmt->u.action.u.vht_group_notif.action_code) {
         case WLAN_VHT_ACTION_OPMODE_NOTIF: {
             struct ieee80211_rx_status *status;
             enum nl80211_band band;
             struct sta_info *sta;
             u8 opmode;
 
             status = IEEE80211_SKB_RXCB(skb);
             band = status->band;
             opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
 
             mutex_lock(&local->sta_mtx);
             sta = sta_info_get_bss(sdata, mgmt->sa);
 
             if (sta)
                 ieee80211_vht_handle_opmode(sdata,
                                 &sta->deflink,
                                 opmode, band);
 
             mutex_unlock(&local->sta_mtx);
             break;
         }
         case WLAN_VHT_ACTION_GROUPID_MGMT:
             ieee80211_process_mu_groups(sdata, &sdata->deflink,
                             mgmt);
             break;
         default:
             WARN_ON(1);
             break;
         }
     } else if (ieee80211_is_action(mgmt->frame_control) &&
            mgmt->u.action.category == WLAN_CATEGORY_S1G) {
         switch (mgmt->u.action.u.s1g.action_code) {
         case WLAN_S1G_TWT_TEARDOWN:
         case WLAN_S1G_TWT_SETUP:
             ieee80211_s1g_rx_twt_action(sdata, skb);
             break;
         default:
             break;
         }
     } else if (ieee80211_is_ext(mgmt->frame_control)) {
         if (sdata->vif.type == NL80211_IFTYPE_STATION)
             ieee80211_sta_rx_queued_ext(sdata, skb);
         else
             WARN_ON(1);
     } else if (ieee80211_is_data_qos(mgmt->frame_control)) {
         struct ieee80211_hdr *hdr = (void *)mgmt;
         struct sta_info *sta;
 
         /*
          * So the frame isn't mgmt, but frame_control
          * is at the right place anyway, of course, so
          * the if statement is correct.
          *
          * Warn if we have other data frame types here,
          * they must not get here.
          */
         WARN_ON(hdr->frame_control &
                 cpu_to_le16(IEEE80211_STYPE_NULLFUNC));
         WARN_ON(!(hdr->seq_ctrl &
                 cpu_to_le16(IEEE80211_SCTL_FRAG)));
         /*
          * This was a fragment of a frame, received while
          * a block-ack session was active. That cannot be
          * right, so terminate the session.
          */
         mutex_lock(&local->sta_mtx);
         sta = sta_info_get_bss(sdata, mgmt->sa);
         if (sta) {
             u16 tid = ieee80211_get_tid(hdr);
 
             __ieee80211_stop_rx_ba_session(
                 sta, tid, WLAN_BACK_RECIPIENT,
                 WLAN_REASON_QSTA_REQUIRE_SETUP,
                 true);
         }
         mutex_unlock(&local->sta_mtx);
     } else switch (sdata->vif.type) {
     case NL80211_IFTYPE_STATION:
         ieee80211_sta_rx_queued_mgmt(sdata, skb);
         break;
     case NL80211_IFTYPE_ADHOC:
         ieee80211_ibss_rx_queued_mgmt(sdata, skb);
         break;
     case NL80211_IFTYPE_MESH_POINT:
         if (!ieee80211_vif_is_mesh(&sdata->vif))
             break;
         ieee80211_mesh_rx_queued_mgmt(sdata, skb);
         break;
     default:
         WARN(1, "frame for unexpected interface type");
         break;
     }
 }
 
 static void ieee80211_iface_process_status(struct ieee80211_sub_if_data *sdata,
                        struct sk_buff *skb)
 {
     struct ieee80211_mgmt *mgmt = (void *)skb->data;
 
     if (ieee80211_is_action(mgmt->frame_control) &&
         mgmt->u.action.category == WLAN_CATEGORY_S1G) {
         switch (mgmt->u.action.u.s1g.action_code) {
         case WLAN_S1G_TWT_TEARDOWN:
         case WLAN_S1G_TWT_SETUP:
             ieee80211_s1g_status_twt_action(sdata, skb);
             break;
         default:
             break;
         }
     }
 }
 
 static void ieee80211_iface_work(struct work_struct *work)
 {
     struct ieee80211_sub_if_data *sdata =
         container_of(work, struct ieee80211_sub_if_data, work);
     struct ieee80211_local *local = sdata->local;
     struct sk_buff *skb;
 
     if (!ieee80211_sdata_running(sdata))
         return;
 
     if (test_bit(SCAN_SW_SCANNING, &local->scanning))
         return;
 
     if (!ieee80211_can_run_worker(local))
         return;
 
     /* first process frames */
     while ((skb = skb_dequeue(&sdata->skb_queue))) {
         kcov_remote_start_common(skb_get_kcov_handle(skb));
 
         if (skb->protocol == cpu_to_be16(ETH_P_TDLS))
             ieee80211_process_tdls_channel_switch(sdata, skb);
         else
             ieee80211_iface_process_skb(local, sdata, skb);
 
         kfree_skb(skb);
         kcov_remote_stop();
     }
 
     /* process status queue */
     while ((skb = skb_dequeue(&sdata->status_queue))) {
         kcov_remote_start_common(skb_get_kcov_handle(skb));
 
         ieee80211_iface_process_status(sdata, skb);
         kfree_skb(skb);
 
         kcov_remote_stop();
     }
 
     /* then other type-dependent work */
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_STATION:
         ieee80211_sta_work(sdata);
         break;
     case NL80211_IFTYPE_ADHOC:
         ieee80211_ibss_work(sdata);
         break;
     case NL80211_IFTYPE_MESH_POINT:
         if (!ieee80211_vif_is_mesh(&sdata->vif))
             break;
         ieee80211_mesh_work(sdata);
         break;
     case NL80211_IFTYPE_OCB:
         ieee80211_ocb_work(sdata);
         break;
     default:
         break;
     }
 }
 
 static void ieee80211_recalc_smps_work(struct work_struct *work)
 {
     struct ieee80211_sub_if_data *sdata =
         container_of(work, struct ieee80211_sub_if_data, recalc_smps);
 
     ieee80211_recalc_smps(sdata, &sdata->deflink);
 }
 
 /*
  * Helper function to initialise an interface to a specific type.
  */
 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
                   enum nl80211_iftype type)
 {
     static const u8 bssid_wildcard[ETH_ALEN] = {0xff, 0xff, 0xff,
                             0xff, 0xff, 0xff};
 
     /* clear type-dependent unions */
     memset(&sdata->u, 0, sizeof(sdata->u));
     memset(&sdata->deflink.u, 0, sizeof(sdata->deflink.u));
 
     /* and set some type-dependent values */
     sdata->vif.type = type;
     sdata->vif.p2p = false;
     sdata->wdev.iftype = type;
 
     sdata->control_port_protocol = cpu_to_be16(ETH_P_PAE);
     sdata->control_port_no_encrypt = false;
     sdata->control_port_over_nl80211 = false;
     sdata->control_port_no_preauth = false;
     sdata->vif.cfg.idle = true;
     sdata->vif.bss_conf.txpower = INT_MIN; /* unset */
 
     sdata->noack_map = 0;
 
     /* only monitor/p2p-device differ */
     if (sdata->dev) {
         sdata->dev->netdev_ops = &ieee80211_dataif_ops;
         sdata->dev->type = ARPHRD_ETHER;
     }
 
     skb_queue_head_init(&sdata->skb_queue);
     skb_queue_head_init(&sdata->status_queue);
     INIT_WORK(&sdata->work, ieee80211_iface_work);
     INIT_WORK(&sdata->recalc_smps, ieee80211_recalc_smps_work);
 
     switch (type) {
     case NL80211_IFTYPE_P2P_GO:
         type = NL80211_IFTYPE_AP;
         sdata->vif.type = type;
         sdata->vif.p2p = true;
         fallthrough;
     case NL80211_IFTYPE_AP:
         skb_queue_head_init(&sdata->u.ap.ps.bc_buf);
         INIT_LIST_HEAD(&sdata->u.ap.vlans);
         sdata->vif.bss_conf.bssid = sdata->vif.addr;
         break;
     case NL80211_IFTYPE_P2P_CLIENT:
         type = NL80211_IFTYPE_STATION;
         sdata->vif.type = type;
         sdata->vif.p2p = true;
         fallthrough;
     case NL80211_IFTYPE_STATION:
         sdata->vif.bss_conf.bssid = sdata->deflink.u.mgd.bssid;
         ieee80211_sta_setup_sdata(sdata);
         break;
     case NL80211_IFTYPE_OCB:
         sdata->vif.bss_conf.bssid = bssid_wildcard;
         ieee80211_ocb_setup_sdata(sdata);
         break;
     case NL80211_IFTYPE_ADHOC:
         sdata->vif.bss_conf.bssid = sdata->u.ibss.bssid;
         ieee80211_ibss_setup_sdata(sdata);
         break;
     case NL80211_IFTYPE_MESH_POINT:
         if (ieee80211_vif_is_mesh(&sdata->vif))
             ieee80211_mesh_init_sdata(sdata);
         break;
     case NL80211_IFTYPE_MONITOR:
         sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
         sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
         sdata->u.mntr.flags = MONITOR_FLAG_CONTROL |
                       MONITOR_FLAG_OTHER_BSS;
         break;
     case NL80211_IFTYPE_NAN:
         idr_init(&sdata->u.nan.function_inst_ids);
         spin_lock_init(&sdata->u.nan.func_lock);
         sdata->vif.bss_conf.bssid = sdata->vif.addr;
         break;
     case NL80211_IFTYPE_AP_VLAN:
     case NL80211_IFTYPE_P2P_DEVICE:
         sdata->vif.bss_conf.bssid = sdata->vif.addr;
         break;
     case NL80211_IFTYPE_UNSPECIFIED:
     case NL80211_IFTYPE_WDS:
     case NUM_NL80211_IFTYPES:
         WARN_ON(1);
         break;
     }
 
     /* need to do this after the switch so vif.type is correct */
     ieee80211_link_setup(&sdata->deflink);
 
     ieee80211_debugfs_add_netdev(sdata);
 }
 
 static int ieee80211_runtime_change_iftype(struct ieee80211_sub_if_data *sdata,
                        enum nl80211_iftype type)
 {
     struct ieee80211_local *local = sdata->local;
     int ret, err;
     enum nl80211_iftype internal_type = type;
     bool p2p = false;
 
     ASSERT_RTNL();
 
     if (!local->ops->change_interface)
         return -EBUSY;
 
     /* for now, don't support changing while links exist */
     if (sdata->vif.valid_links)
         return -EBUSY;
 
     switch (sdata->vif.type) {
     case NL80211_IFTYPE_AP:
         if (!list_empty(&sdata->u.ap.vlans))
             return -EBUSY;
         break;
     case NL80211_IFTYPE_STATION:
     case NL80211_IFTYPE_ADHOC:
     case NL80211_IFTYPE_OCB:
         /*
          * Could maybe also all others here?
          * Just not sure how that interacts
          * with the RX/config path e.g. for
          * mesh.
          */
         break;
     default:
         return -EBUSY;
     }
 
     switch (type) {
     case NL80211_IFTYPE_AP:
     case NL80211_IFTYPE_STATION:
     case NL80211_IFTYPE_ADHOC:
     case NL80211_IFTYPE_OCB:
         /*
          * Could probably support everything
          * but here.
          */
         break;
     case NL80211_IFTYPE_P2P_CLIENT:
         p2p = true;
         internal_type = NL80211_IFTYPE_STATION;
         break;
     case NL80211_IFTYPE_P2P_GO:
         p2p = true;
         internal_type = NL80211_IFTYPE_AP;
         break;
     default:
         return -EBUSY;
     }
 
     ret = ieee80211_check_concurrent_iface(sdata, internal_type);
     if (ret)
         return ret;
 
     ieee80211_stop_vif_queues(local, sdata,
                   IEEE80211_QUEUE_STOP_REASON_IFTYPE_CHANGE);
     synchronize_net();
 
     ieee80211_do_stop(sdata, false);
 
     ieee80211_teardown_sdata(sdata);
 
     ieee80211_set_sdata_offload_flags(sdata);
     ret = drv_change_interface(local, sdata, internal_type, p2p);
     if (ret)
         type = ieee80211_vif_type_p2p(&sdata->vif);
 
     /*
      * Ignore return value here, there's not much we can do since
      * the driver changed the interface type internally already.
      * The warnings will hopefully make driver authors fix it :-)
      */
     ieee80211_check_queues(sdata, type);
 
     ieee80211_setup_sdata(sdata, type);
     ieee80211_set_vif_encap_ops(sdata);
 
     err = ieee80211_do_open(&sdata->wdev, false);
     WARN(err, "type change: do_open returned %d", err);
 
     ieee80211_wake_vif_queues(local, sdata,
                   IEEE80211_QUEUE_STOP_REASON_IFTYPE_CHANGE);
     return ret;
 }
 
 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
                  enum nl80211_iftype type)
 {
     int ret;
 
     ASSERT_RTNL();
 
     if (type == ieee80211_vif_type_p2p(&sdata->vif))
         return 0;
 
     if (ieee80211_sdata_running(sdata)) {
         ret = ieee80211_runtime_change_iftype(sdata, type);
         if (ret)
             return ret;
     } else {
         /* Purge and reset type-dependent state. */
         ieee80211_teardown_sdata(sdata);
         ieee80211_setup_sdata(sdata, type);
     }
 
     /* reset some values that shouldn't be kept across type changes */
     if (type == NL80211_IFTYPE_STATION)
         sdata->u.mgd.use_4addr = false;
 
     return 0;
 }
 
 static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
                        u8 *perm_addr, enum nl80211_iftype type)
 {
     struct ieee80211_sub_if_data *sdata;
     u64 mask, start, addr, val, inc;
     u8 *m;
     u8 tmp_addr[ETH_ALEN];
     int i;
 
     /* default ... something at least */
     memcpy(perm_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
 
     if (is_zero_ether_addr(local->hw.wiphy->addr_mask) &&
         local->hw.wiphy->n_addresses <= 1)
         return;
 
     mutex_lock(&local->iflist_mtx);
 
     switch (type) {
     case NL80211_IFTYPE_MONITOR:
         /* doesn't matter */
         break;
     case NL80211_IFTYPE_AP_VLAN:
         /* match up with an AP interface */
         list_for_each_entry(sdata, &local->interfaces, list) {
             if (sdata->vif.type != NL80211_IFTYPE_AP)
                 continue;
             memcpy(perm_addr, sdata->vif.addr, ETH_ALEN);
             break;
         }
         /* keep default if no AP interface present */
         break;
     case NL80211_IFTYPE_P2P_CLIENT:
     case NL80211_IFTYPE_P2P_GO:
         if (ieee80211_hw_check(&local->hw, P2P_DEV_ADDR_FOR_INTF)) {
             list_for_each_entry(sdata, &local->interfaces, list) {
                 if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE)
                     continue;
                 if (!ieee80211_sdata_running(sdata))
                     continue;
                 memcpy(perm_addr, sdata->vif.addr, ETH_ALEN);
                 goto out_unlock;
             }
         }
         fallthrough;
     default:
         /* assign a new address if possible -- try n_addresses first */
         for (i = 0; i < local->hw.wiphy->n_addresses; i++) {
             bool used = false;
 
             list_for_each_entry(sdata, &local->interfaces, list) {
                 if (ether_addr_equal(local->hw.wiphy->addresses[i].addr,
                              sdata->vif.addr)) {
                     used = true;
                     break;
                 }
             }
 
             if (!used) {
                 memcpy(perm_addr,
                        local->hw.wiphy->addresses[i].addr,
                        ETH_ALEN);
                 break;
             }
         }
 
         /* try mask if available */
         if (is_zero_ether_addr(local->hw.wiphy->addr_mask))
             break;
 
         m = local->hw.wiphy->addr_mask;
         mask =  ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
             ((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
             ((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
 
         if (__ffs64(mask) + hweight64(mask) != fls64(mask)) {
             /* not a contiguous mask ... not handled now! */
             pr_info("not contiguous\n");
             break;
         }
 
         /*
          * Pick address of existing interface in case user changed
          * MAC address manually, default to perm_addr.
          */
         m = local->hw.wiphy->perm_addr;
         list_for_each_entry(sdata, &local->interfaces, list) {
             if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
                 continue;
             m = sdata->vif.addr;
             break;
         }
         start = ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
             ((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
             ((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
 
         inc = 1ULL<<__ffs64(mask);
         val = (start & mask);
         addr = (start & ~mask) | (val & mask);
         do {
             bool used = false;
 
             tmp_addr[5] = addr >> 0*8;
             tmp_addr[4] = addr >> 1*8;
             tmp_addr[3] = addr >> 2*8;
             tmp_addr[2] = addr >> 3*8;
             tmp_addr[1] = addr >> 4*8;
             tmp_addr[0] = addr >> 5*8;
 
             val += inc;
 
             list_for_each_entry(sdata, &local->interfaces, list) {
                 if (ether_addr_equal(tmp_addr, sdata->vif.addr)) {
                     used = true;
                     break;
                 }
             }
 
             if (!used) {
                 memcpy(perm_addr, tmp_addr, ETH_ALEN);
                 break;
             }
             addr = (start & ~mask) | (val & mask);
         } while (addr != start);
 
         break;
     }
 
  out_unlock:
     mutex_unlock(&local->iflist_mtx);
 }
 
 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
              unsigned char name_assign_type,
              struct wireless_dev **new_wdev, enum nl80211_iftype type,
              struct vif_params *params)
 {
     struct net_device *ndev = NULL;
     struct ieee80211_sub_if_data *sdata = NULL;
     struct txq_info *txqi;
     void (*if_setup)(struct net_device *dev);
     int ret, i;
     int txqs = 1;
 
     ASSERT_RTNL();
 
     if (type == NL80211_IFTYPE_P2P_DEVICE || type == NL80211_IFTYPE_NAN) {
         struct wireless_dev *wdev;
 
         sdata = kzalloc(sizeof(*sdata) + local->hw.vif_data_size,
                 GFP_KERNEL);
         if (!sdata)
             return -ENOMEM;
         wdev = &sdata->wdev;
 
         sdata->dev = NULL;
         strlcpy(sdata->name, name, IFNAMSIZ);
         ieee80211_assign_perm_addr(local, wdev->address, type);
         memcpy(sdata->vif.addr, wdev->address, ETH_ALEN);
         ether_addr_copy(sdata->vif.bss_conf.addr, sdata->vif.addr);
     } else {
         int size = ALIGN(sizeof(*sdata) + local->hw.vif_data_size,
                  sizeof(void *));
         int txq_size = 0;
 
         if (local->ops->wake_tx_queue &&
             type != NL80211_IFTYPE_AP_VLAN &&
             (type != NL80211_IFTYPE_MONITOR ||
              (params->flags & MONITOR_FLAG_ACTIVE)))
             txq_size += sizeof(struct txq_info) +
                     local->hw.txq_data_size;
 
         if (local->ops->wake_tx_queue) {
             if_setup = ieee80211_if_setup_no_queue;
         } else {
             if_setup = ieee80211_if_setup;
             if (local->hw.queues >= IEEE80211_NUM_ACS)
                 txqs = IEEE80211_NUM_ACS;
         }
 
         ndev = alloc_netdev_mqs(size + txq_size,
                     name, name_assign_type,
                     if_setup, txqs, 1);
         if (!ndev)
             return -ENOMEM;
 
         if (!local->ops->wake_tx_queue && local->hw.wiphy->tx_queue_len)
             ndev->tx_queue_len = local->hw.wiphy->tx_queue_len;
 
         dev_net_set(ndev, wiphy_net(local->hw.wiphy));
 
         ndev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
         if (!ndev->tstats) {
             free_netdev(ndev);
             return -ENOMEM;
         }
 
         ndev->needed_headroom = local->tx_headroom +
                     4*6 /* four MAC addresses */
                     + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
                     + 6 /* mesh */
                     + 8 /* rfc1042/bridge tunnel */
                     - ETH_HLEN /* ethernet hard_header_len */
                     + IEEE80211_ENCRYPT_HEADROOM;
         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
 
         ret = dev_alloc_name(ndev, ndev->name);
         if (ret < 0) {
             ieee80211_if_free(ndev);
             free_netdev(ndev);
             return ret;
         }
 
         ieee80211_assign_perm_addr(local, ndev->perm_addr, type);
         if (is_valid_ether_addr(params->macaddr))
             eth_hw_addr_set(ndev, params->macaddr);
         else
             eth_hw_addr_set(ndev, ndev->perm_addr);
         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 
         /* don't use IEEE80211_DEV_TO_SUB_IF -- it checks too much */
         sdata = netdev_priv(ndev);
         ndev->ieee80211_ptr = &sdata->wdev;
         memcpy(sdata->vif.addr, ndev->dev_addr, ETH_ALEN);
         ether_addr_copy(sdata->vif.bss_conf.addr, sdata->vif.addr);
         memcpy(sdata->name, ndev->name, IFNAMSIZ);
 
         if (txq_size) {
             txqi = netdev_priv(ndev) + size;
             ieee80211_txq_init(sdata, NULL, txqi, 0);
         }
 
         sdata->dev = ndev;
     }
 
     /* initialise type-independent data */
     sdata->wdev.wiphy = local->hw.wiphy;
 
     ieee80211_sdata_init(local, sdata);
 
     ieee80211_init_frag_cache(&sdata->frags);
 
     INIT_LIST_HEAD(&sdata->key_list);
 
     INIT_DELAYED_WORK(&sdata->dec_tailroom_needed_wk,
               ieee80211_delayed_tailroom_dec);
 
     for (i = 0; i < NUM_NL80211_BANDS; i++) {
         struct ieee80211_supported_band *sband;
         sband = local->hw.wiphy->bands[i];
         sdata->rc_rateidx_mask[i] =
             sband ? (1 << sband->n_bitrates) - 1 : 0;
         if (sband) {
             __le16 cap;
             u16 *vht_rate_mask;
 
             memcpy(sdata->rc_rateidx_mcs_mask[i],
                    sband->ht_cap.mcs.rx_mask,
                    sizeof(sdata->rc_rateidx_mcs_mask[i]));
 
             cap = sband->vht_cap.vht_mcs.rx_mcs_map;
             vht_rate_mask = sdata->rc_rateidx_vht_mcs_mask[i];
             ieee80211_get_vht_mask_from_cap(cap, vht_rate_mask);
         } else {
             memset(sdata->rc_rateidx_mcs_mask[i], 0,
                    sizeof(sdata->rc_rateidx_mcs_mask[i]));
             memset(sdata->rc_rateidx_vht_mcs_mask[i], 0,
                    sizeof(sdata->rc_rateidx_vht_mcs_mask[i]));
         }
     }
 
     ieee80211_set_default_queues(sdata);
 
     sdata->deflink.ap_power_level = IEEE80211_UNSET_POWER_LEVEL;
     sdata->deflink.user_power_level = local->user_power_level;
 
     /* setup type-dependent data */
     ieee80211_setup_sdata(sdata, type);
 
     if (ndev) {
         ndev->ieee80211_ptr->use_4addr = params->use_4addr;
         if (type == NL80211_IFTYPE_STATION)
             sdata->u.mgd.use_4addr = params->use_4addr;
 
         ndev->features |= local->hw.netdev_features;
         ndev->hw_features |= ndev->features &
                     MAC80211_SUPPORTED_FEATURES_TX;
 
         netdev_set_default_ethtool_ops(ndev, &ieee80211_ethtool_ops);
 
         /* MTU range is normally 256 - 2304, where the upper limit is
          * the maximum MSDU size. Monitor interfaces send and receive
          * MPDU and A-MSDU frames which may be much larger so we do
          * not impose an upper limit in that case.
          */
         ndev->min_mtu = 256;
         if (type == NL80211_IFTYPE_MONITOR)
             ndev->max_mtu = 0;
         else
             ndev->max_mtu = local->hw.max_mtu;
 
         ret = cfg80211_register_netdevice(ndev);
         if (ret) {
             free_netdev(ndev);
             return ret;
         }
     }
 
     mutex_lock(&local->iflist_mtx);
     list_add_tail_rcu(&sdata->list, &local->interfaces);
     mutex_unlock(&local->iflist_mtx);
 
     if (new_wdev)
         *new_wdev = &sdata->wdev;
 
     return 0;
 }
 
 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
 {
     ASSERT_RTNL();
 
     mutex_lock(&sdata->local->iflist_mtx);
     list_del_rcu(&sdata->list);
     mutex_unlock(&sdata->local->iflist_mtx);
 
     if (sdata->vif.txq)
         ieee80211_txq_purge(sdata->local, to_txq_info(sdata->vif.txq));
 
     synchronize_rcu();
 
     cfg80211_unregister_wdev(&sdata->wdev);
 
     if (!sdata->dev) {
         ieee80211_teardown_sdata(sdata);
         kfree(sdata);
     }
 }
 
 void ieee80211_sdata_stop(struct ieee80211_sub_if_data *sdata)
 {
     if (WARN_ON_ONCE(!test_bit(SDATA_STATE_RUNNING, &sdata->state)))
         return;
     ieee80211_do_stop(sdata, true);
 }
 
 void ieee80211_remove_interfaces(struct ieee80211_local *local)
 {
     struct ieee80211_sub_if_data *sdata, *tmp;
     LIST_HEAD(unreg_list);
     LIST_HEAD(wdev_list);
 
     ASSERT_RTNL();
 
     /* Before destroying the interfaces, make sure they're all stopped so
      * that the hardware is stopped. Otherwise, the driver might still be
      * iterating the interfaces during the shutdown, e.g. from a worker
      * or from RX processing or similar, and if it does so (using atomic
      * iteration) while we're manipulating the list, the iteration will
      * crash.
      *
      * After this, the hardware should be stopped and the driver should
      * have stopped all of its activities, so that we can do RCU-unaware
      * manipulations of the interface list below.
      */
     cfg80211_shutdown_all_interfaces(local->hw.wiphy);
 
     WARN(local->open_count, "%s: open count remains %d\n",
          wiphy_name(local->hw.wiphy), local->open_count);
 
     ieee80211_txq_teardown_flows(local);
 
     mutex_lock(&local->iflist_mtx);
     list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
         list_del(&sdata->list);
 
         if (sdata->dev)
             unregister_netdevice_queue(sdata->dev, &unreg_list);
         else
             list_add(&sdata->list, &wdev_list);
     }
     mutex_unlock(&local->iflist_mtx);
 
     unregister_netdevice_many(&unreg_list);
 
     wiphy_lock(local->hw.wiphy);
     list_for_each_entry_safe(sdata, tmp, &wdev_list, list) {
         list_del(&sdata->list);
         cfg80211_unregister_wdev(&sdata->wdev);
         kfree(sdata);
     }
     wiphy_unlock(local->hw.wiphy);
 }
 
 static int netdev_notify(struct notifier_block *nb,
              unsigned long state, void *ptr)
 {
     struct net_device *dev = netdev_notifier_info_to_dev(ptr);
     struct ieee80211_sub_if_data *sdata;
 
     if (state != NETDEV_CHANGENAME)
         return NOTIFY_DONE;
 
     if (!dev->ieee80211_ptr || !dev->ieee80211_ptr->wiphy)
         return NOTIFY_DONE;
 
     if (dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
         return NOTIFY_DONE;
 
     sdata = IEEE80211_DEV_TO_SUB_IF(dev);
     memcpy(sdata->name, dev->name, IFNAMSIZ);
     ieee80211_debugfs_rename_netdev(sdata);
 
     return NOTIFY_OK;
 }
 
 static struct notifier_block mac80211_netdev_notifier = {
     .notifier_call = netdev_notify,
 };
 
 int ieee80211_iface_init(void)
 {
     return register_netdevice_notifier(&mac80211_netdev_notifier);
 }
 
 void ieee80211_iface_exit(void)
 {
     unregister_netdevice_notifier(&mac80211_netdev_notifier);
 }
 
 void ieee80211_vif_inc_num_mcast(struct ieee80211_sub_if_data *sdata)
 {
     if (sdata->vif.type == NL80211_IFTYPE_AP)
         atomic_inc(&sdata->u.ap.num_mcast_sta);
     else if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
         atomic_inc(&sdata->u.vlan.num_mcast_sta);
 }
 
 void ieee80211_vif_dec_num_mcast(struct ieee80211_sub_if_data *sdata)
 {
     if (sdata->vif.type == NL80211_IFTYPE_AP)
         atomic_dec(&sdata->u.ap.num_mcast_sta);
     else if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
         atomic_dec(&sdata->u.vlan.num_mcast_sta);
 }