mac80211: avoid transmitting delBA to old AP

When roaming while we have active BA session,
we can end up transmitting delBA frames to
the old AP while we're already on the new AP's
channel, which can cause warnings.

Simply avoid sending those frames, but still
tear down the internal session state, since
they are not really necessary anyway as we
will implicitly disassociate when sending the
association to the new AP.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

11 files changed, 48 insertions, 35 deletions

diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 58eab9e..720b7a8 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -56,7 +56,7 @@ static void ieee80211_free_tid_rx(struct rcu_head *h)
 }
 
 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				     u16 initiator, u16 reason)
+				     u16 initiator, u16 reason, bool tx)
 {
 	struct ieee80211_local *local = sta->local;
 	struct tid_ampdu_rx *tid_rx;
@@ -81,7 +81,7 @@ void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
 				"aggregation for tid %d\n", tid);
 
 	/* check if this is a self generated aggregation halt */
-	if (initiator == WLAN_BACK_RECIPIENT)
+	if (initiator == WLAN_BACK_RECIPIENT && tx)
 		ieee80211_send_delba(sta->sdata, sta->sta.addr,
 				     tid, 0, reason);
 
@@ -92,10 +92,10 @@ void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
 }
 
 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				    u16 initiator, u16 reason)
+				    u16 initiator, u16 reason, bool tx)
 {
 	mutex_lock(&sta->ampdu_mlme.mtx);
-	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason);
+	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 }
 
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 8f23401..d4679b2 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -145,7 +145,8 @@ static void kfree_tid_tx(struct rcu_head *rcu_head)
 }
 
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				    enum ieee80211_back_parties initiator)
+				    enum ieee80211_back_parties initiator,
+				    bool tx)
 {
 	struct ieee80211_local *local = sta->local;
 	struct tid_ampdu_tx *tid_tx = sta->ampdu_mlme.tid_tx[tid];
@@ -185,6 +186,7 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 	clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
 
 	tid_tx->stop_initiator = initiator;
+	tid_tx->tx_stop = tx;
 
 	ret = drv_ampdu_action(local, sta->sdata,
 			       IEEE80211_AMPDU_TX_STOP,
@@ -577,13 +579,14 @@ void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
 
 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				   enum ieee80211_back_parties initiator)
+				   enum ieee80211_back_parties initiator,
+				   bool tx)
 {
 	int ret;
 
 	mutex_lock(&sta->ampdu_mlme.mtx);
 
-	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator);
+	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
 
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 
@@ -672,7 +675,7 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
 		goto unlock_sta;
 	}
 
-	if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR)
+	if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
 		ieee80211_send_delba(sta->sdata, ra, tid,
 			WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 
@@ -772,7 +775,8 @@ void ieee80211_process_addba_resp(struct ieee80211_local *local,
 
 		sta->ampdu_mlme.addba_req_num[tid] = 0;
 	} else {
-		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
+		___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
+						true);
 	}
 
  out:
diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index 6b7ff9f..50c40ea 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -196,7 +196,8 @@ static ssize_t sta_agg_status_write(struct file *file, const char __user *userbu
 		else
 			ret = ieee80211_stop_tx_ba_session(&sta->sta, tid);
 	} else {
-		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT, 3);
+		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
+					       3, true);
 		ret = 0;
 	}
 
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index 11f74f5..4214bb6 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -101,16 +101,16 @@ void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
 		ht_cap->mcs.rx_mask[32/8] |= 1;
 }
 
-void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta)
+void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx)
 {
 	int i;
 
 	cancel_work_sync(&sta->ampdu_mlme.work);
 
 	for (i = 0; i <  STA_TID_NUM; i++) {
-		__ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR);
+		__ieee80211_stop_tx_ba_session(sta, i, WLAN_BACK_INITIATOR, tx);
 		__ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT,
-					       WLAN_REASON_QSTA_LEAVE_QBSS);
+					       WLAN_REASON_QSTA_LEAVE_QBSS, tx);
 	}
 }
 
@@ -135,7 +135,7 @@ void ieee80211_ba_session_work(struct work_struct *work)
 		if (test_and_clear_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired))
 			___ieee80211_stop_rx_ba_session(
 				sta, tid, WLAN_BACK_RECIPIENT,
-				WLAN_REASON_QSTA_TIMEOUT);
+				WLAN_REASON_QSTA_TIMEOUT, true);
 
 		tid_tx = sta->ampdu_mlme.tid_tx[tid];
 		if (!tid_tx)
@@ -146,7 +146,8 @@ void ieee80211_ba_session_work(struct work_struct *work)
 		else if (test_and_clear_bit(HT_AGG_STATE_WANT_STOP,
 					    &tid_tx->state))
 			___ieee80211_stop_tx_ba_session(sta, tid,
-							WLAN_BACK_INITIATOR);
+							WLAN_BACK_INITIATOR,
+							true);
 	}
 	mutex_unlock(&sta->ampdu_mlme.mtx);
 }
@@ -214,9 +215,11 @@ void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 #endif /* CONFIG_MAC80211_HT_DEBUG */
 
 	if (initiator == WLAN_BACK_INITIATOR)
-		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0);
+		__ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_INITIATOR, 0,
+					       true);
 	else
-		__ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT);
+		__ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
+					       true);
 }
 
 int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 08509e2..76c2b50 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1175,10 +1175,10 @@ int ieee80211_send_smps_action(struct ieee80211_sub_if_data *sdata,
 void ieee80211_request_smps_work(struct work_struct *work);
 
 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				     u16 initiator, u16 reason);
+				     u16 initiator, u16 reason, bool stop);
 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
-				    u16 initiator, u16 reason);
-void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta);
+				    u16 initiator, u16 reason, bool stop);
+void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, bool tx);
 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 			     struct sta_info *sta,
 			     struct ieee80211_mgmt *mgmt, size_t len);
@@ -1192,9 +1192,11 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
 				     size_t len);
 
 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				   enum ieee80211_back_parties initiator);
+				   enum ieee80211_back_parties initiator,
+				   bool tx);
 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
-				    enum ieee80211_back_parties initiator);
+				    enum ieee80211_back_parties initiator,
+				    bool tx);
 void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid);
 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid);
 void ieee80211_ba_session_work(struct work_struct *work);
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 438a2f5..e99d1b6 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -796,7 +796,8 @@ static void ieee80211_iface_work(struct work_struct *work)
 
 				__ieee80211_stop_rx_ba_session(
 					sta, tid, WLAN_BACK_RECIPIENT,
-					WLAN_REASON_QSTA_REQUIRE_SETUP);
+					WLAN_REASON_QSTA_REQUIRE_SETUP,
+					true);
 			}
 			mutex_unlock(&local->sta_mtx);
 		} else switch (sdata->vif.type) {
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index cd13aa8..5695c94 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -921,7 +921,7 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
 }
 
 static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
-				   bool remove_sta)
+				   bool remove_sta, bool tx)
 {
 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 	struct ieee80211_local *local = sdata->local;
@@ -960,7 +960,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 	sta = sta_info_get(sdata, bssid);
 	if (sta) {
 		set_sta_flags(sta, WLAN_STA_BLOCK_BA);
-		ieee80211_sta_tear_down_BA_sessions(sta);
+		ieee80211_sta_tear_down_BA_sessions(sta, tx);
 	}
 	mutex_unlock(&local->sta_mtx);
 
@@ -1124,7 +1124,7 @@ static void __ieee80211_connection_loss(struct ieee80211_sub_if_data *sdata)
 
 	printk(KERN_DEBUG "Connection to AP %pM lost.\n", bssid);
 
-	ieee80211_set_disassoc(sdata, true);
+	ieee80211_set_disassoc(sdata, true, true);
 	mutex_unlock(&ifmgd->mtx);
 
 	mutex_lock(&local->mtx);
@@ -1197,7 +1197,7 @@ ieee80211_rx_mgmt_deauth(struct ieee80211_sub_if_data *sdata,
 	printk(KERN_DEBUG "%s: deauthenticated from %pM (Reason: %u)\n",
 			sdata->name, bssid, reason_code);
 
-	ieee80211_set_disassoc(sdata, true);
+	ieee80211_set_disassoc(sdata, true, false);
 	mutex_lock(&sdata->local->mtx);
 	ieee80211_recalc_idle(sdata->local);
 	mutex_unlock(&sdata->local->mtx);
@@ -1229,7 +1229,7 @@ ieee80211_rx_mgmt_disassoc(struct ieee80211_sub_if_data *sdata,
 	printk(KERN_DEBUG "%s: disassociated from %pM (Reason: %u)\n",
 			sdata->name, mgmt->sa, reason_code);
 
-	ieee80211_set_disassoc(sdata, true);
+	ieee80211_set_disassoc(sdata, true, false);
 	mutex_lock(&sdata->local->mtx);
 	ieee80211_recalc_idle(sdata->local);
 	mutex_unlock(&sdata->local->mtx);
@@ -1880,7 +1880,7 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
 			printk(KERN_DEBUG "No probe response from AP %pM"
 				" after %dms, disconnecting.\n",
 				bssid, (1000 * IEEE80211_PROBE_WAIT)/HZ);
-			ieee80211_set_disassoc(sdata, true);
+			ieee80211_set_disassoc(sdata, true, true);
 			mutex_unlock(&ifmgd->mtx);
 			mutex_lock(&local->mtx);
 			ieee80211_recalc_idle(local);
@@ -2204,7 +2204,7 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
 		}
 
 		/* Trying to reassociate - clear previous association state */
-		ieee80211_set_disassoc(sdata, true);
+		ieee80211_set_disassoc(sdata, true, false);
 	}
 	mutex_unlock(&ifmgd->mtx);
 
@@ -2318,7 +2318,7 @@ int ieee80211_mgd_deauth(struct ieee80211_sub_if_data *sdata,
 
 	memcpy(bssid, req->bss->bssid, ETH_ALEN);
 	if (ifmgd->associated == req->bss) {
-		ieee80211_set_disassoc(sdata, false);
+		ieee80211_set_disassoc(sdata, false, true);
 		mutex_unlock(&ifmgd->mtx);
 		assoc_bss = true;
 	} else {
@@ -2401,7 +2401,7 @@ int ieee80211_mgd_disassoc(struct ieee80211_sub_if_data *sdata,
 	       sdata->name, req->bss->bssid, req->reason_code);
 
 	memcpy(bssid, req->bss->bssid, ETH_ALEN);
-	ieee80211_set_disassoc(sdata, false);
+	ieee80211_set_disassoc(sdata, false, true);
 
 	mutex_unlock(&ifmgd->mtx);
 
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index ce671df..e3e2bce 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -46,7 +46,7 @@ int __ieee80211_suspend(struct ieee80211_hw *hw)
 	list_for_each_entry(sta, &local->sta_list, list) {
 		if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) {
 			set_sta_flags(sta, WLAN_STA_BLOCK_BA);
-			ieee80211_sta_tear_down_BA_sessions(sta);
+			ieee80211_sta_tear_down_BA_sessions(sta, true);
 		}
 
 		if (sta->uploaded) {
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index ca2cba9..aeaf2d6 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -633,7 +633,7 @@ static int __must_check __sta_info_destroy(struct sta_info *sta)
 	 * will be sufficient.
 	 */
 	set_sta_flags(sta, WLAN_STA_BLOCK_BA);
-	ieee80211_sta_tear_down_BA_sessions(sta);
+	ieee80211_sta_tear_down_BA_sessions(sta, true);
 
 	spin_lock_irqsave(&local->sta_lock, flags);
 	ret = sta_info_hash_del(local, sta);
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 810c5ce..cf21a2e 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -79,6 +79,7 @@ enum ieee80211_sta_info_flags {
  * @dialog_token: dialog token for aggregation session
  * @state: session state (see above)
  * @stop_initiator: initiator of a session stop
+ * @tx_stop: TX DelBA frame when stopping
  *
  * This structure is protected by RCU and the per-station
  * spinlock. Assignments to the array holding it must hold
@@ -95,6 +96,7 @@ struct tid_ampdu_tx {
 	unsigned long state;
 	u8 dialog_token;
 	u8 stop_initiator;
+	bool tx_stop;
 };
 
 /**
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 4ee8f2b..0b6fc92 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1221,7 +1221,7 @@ int ieee80211_reconfig(struct ieee80211_local *local)
 		mutex_lock(&local->sta_mtx);
 
 		list_for_each_entry(sta, &local->sta_list, list) {
-			ieee80211_sta_tear_down_BA_sessions(sta);
+			ieee80211_sta_tear_down_BA_sessions(sta, true);
 			clear_sta_flags(sta, WLAN_STA_BLOCK_BA);
 		}