mac80211: abort CSA if beacon does not include CSA IEs

In case we receive a beacon without CSA IE while we are in
the middle of channel switch - abort the operation.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 37 insertions, 6 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 1b4938d100d5..28a275ec6700 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1259,6 +1259,32 @@ static void ieee80211_chswitch_timer(struct timer_list *t)
 }
 
 static void
+ieee80211_sta_abort_chanswitch(struct ieee80211_sub_if_data *sdata)
+{
+        struct ieee80211_local *local = sdata->local;
+
+        if (!local->ops->abort_channel_switch)
+                return;
+
+        mutex_lock(&local->mtx);
+
+        mutex_lock(&local->chanctx_mtx);
+        ieee80211_vif_unreserve_chanctx(sdata);
+        mutex_unlock(&local->chanctx_mtx);
+
+        if (sdata->csa_block_tx)
+                ieee80211_wake_vif_queues(local, sdata,
+                                          IEEE80211_QUEUE_STOP_REASON_CSA);
+
+        sdata->csa_block_tx = false;
+        sdata->vif.csa_active = false;
+
+        mutex_unlock(&local->mtx);
+
+        drv_abort_channel_switch(sdata);
+}
+
+static void
 ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
                                  u64 timestamp, u32 device_timestamp,
                                  struct ieee802_11_elems *elems,
@@ -1282,19 +1308,24 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
         if (local->scanning)
                 return;
 
-        /* disregard subsequent announcements if we are already processing */
-        if (sdata->vif.csa_active)
-                return;
-
         current_band = cbss->channel->band;
         res = ieee80211_parse_ch_switch_ie(sdata, elems, current_band,
                                            ifmgd->flags,
                                            ifmgd->associated->bssid, &csa_ie);
-        if (res < 0)
+        if (res < 0) {
                 ieee80211_queue_work(&local->hw,
                                      &ifmgd->csa_connection_drop_work);
-        if (res)
                 return;
+        }
+
+        if (res && beacon && sdata->vif.csa_active &&
+            !ifmgd->csa_waiting_bcn) {
+                ieee80211_sta_abort_chanswitch(sdata);
+                return;
+        } else if (sdata->vif.csa_active || res) {
+                /* disregard subsequent announcements if already processing */
+                return;
+        }
 
         if (!cfg80211_chandef_usable(local->hw.wiphy, &csa_ie.chandef,
                                      IEEE80211_CHAN_DISABLED)) {