1 files changed, 102 insertions, 9 deletions

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index 1fadf5faafb8..106e2530b64e 100644
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -4317,6 +4317,40 @@ static int ath11k_clear_peer_keys(struct ath11k_vif *arvif,
 	return first_errno;
 }
 
+static int ath11k_set_group_keys(struct ath11k_vif *arvif)
+{
+	struct ath11k *ar = arvif->ar;
+	struct ath11k_base *ab = ar->ab;
+	const u8 *addr = arvif->bssid;
+	int i, ret, first_errno = 0;
+	struct ath11k_peer *peer;
+
+	spin_lock_bh(&ab->base_lock);
+	peer = ath11k_peer_find(ab, arvif->vdev_id, addr);
+	spin_unlock_bh(&ab->base_lock);
+
+	if (!peer)
+		return -ENOENT;
+
+	for (i = 0; i < ARRAY_SIZE(peer->keys); i++) {
+		struct ieee80211_key_conf *key = peer->keys[i];
+
+		if (!key || (key->flags & IEEE80211_KEY_FLAG_PAIRWISE))
+			continue;
+
+		ret = ath11k_install_key(arvif, key, SET_KEY, addr,
+					 WMI_KEY_GROUP);
+		if (ret < 0 && first_errno == 0)
+			first_errno = ret;
+
+		if (ret < 0)
+			ath11k_warn(ab, "failed to set group key of idx %d for vdev %d: %d\n",
+				    i, arvif->vdev_id, ret);
+	}
+
+	return first_errno;
+}
+
 static int ath11k_mac_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 				 struct ieee80211_vif *vif, struct ieee80211_sta *sta,
 				 struct ieee80211_key_conf *key)
@@ -4326,6 +4360,7 @@ static int ath11k_mac_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 	struct ath11k_vif *arvif = ath11k_vif_to_arvif(vif);
 	struct ath11k_peer *peer;
 	struct ath11k_sta *arsta;
+	bool is_ap_with_no_sta;
 	const u8 *peer_addr;
 	int ret = 0;
 	u32 flags = 0;
@@ -4386,16 +4421,57 @@ static int ath11k_mac_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 	else
 		flags |= WMI_KEY_GROUP;
 
-	ret = ath11k_install_key(arvif, key, cmd, peer_addr, flags);
-	if (ret) {
-		ath11k_warn(ab, "ath11k_install_key failed (%d)\n", ret);
-		goto exit;
-	}
+	ath11k_dbg(ar->ab, ATH11K_DBG_MAC,
+		   "%s for peer %pM on vdev %d flags 0x%X, type = %d, num_sta %d\n",
+		   cmd == SET_KEY ? "SET_KEY" : "DEL_KEY", peer_addr, arvif->vdev_id,
+		   flags, arvif->vdev_type, arvif->num_stations);
+
+	/* Allow group key clearing only in AP mode when no stations are
+	 * associated. There is a known race condition in firmware where
+	 * group addressed packets may be dropped if the key is cleared
+	 * and immediately set again during rekey.
+	 *
+	 * During GTK rekey, mac80211 issues a clear key (if the old key
+	 * exists) followed by an install key operation for same key
+	 * index. This causes ath11k to send two WMI commands in quick
+	 * succession: one to clear the old key and another to install the
+	 * new key in the same slot.
+	 *
+	 * Under certain conditions—especially under high load or time
+	 * sensitive scenarios, firmware may process these commands
+	 * asynchronously in a way that firmware assumes the key is
+	 * cleared whereas hardware has a valid key. This inconsistency
+	 * between hardware and firmware leads to group addressed packet
+	 * drops after rekey.
+	 * Only setting the same key again can restore a valid key in
+	 * firmware and allow packets to be transmitted.
+	 *
+	 * There is a use case where an AP can transition from Secure mode
+	 * to open mode without a vdev restart by just deleting all
+	 * associated peers and clearing key, Hence allow clear key for
+	 * that case alone. Mark arvif->reinstall_group_keys in such cases
+	 * and reinstall the same key when the first peer is added,
+	 * allowing firmware to recover from the race if it had occurred.
+	 */
 
-	ret = ath11k_dp_peer_rx_pn_replay_config(arvif, peer_addr, cmd, key);
-	if (ret) {
-		ath11k_warn(ab, "failed to offload PN replay detection %d\n", ret);
-		goto exit;
+	is_ap_with_no_sta = (vif->type == NL80211_IFTYPE_AP &&
+			     !arvif->num_stations);
+	if ((flags & WMI_KEY_PAIRWISE) || cmd == SET_KEY || is_ap_with_no_sta) {
+		ret = ath11k_install_key(arvif, key, cmd, peer_addr, flags);
+		if (ret) {
+			ath11k_warn(ab, "ath11k_install_key failed (%d)\n", ret);
+			goto exit;
+		}
+
+		ret = ath11k_dp_peer_rx_pn_replay_config(arvif, peer_addr, cmd, key);
+		if (ret) {
+			ath11k_warn(ab, "failed to offload PN replay detection %d\n",
+				    ret);
+			goto exit;
+		}
+
+		if ((flags & WMI_KEY_GROUP) && cmd == SET_KEY && is_ap_with_no_sta)
+			arvif->reinstall_group_keys = true;
 	}
 
 	spin_lock_bh(&ab->base_lock);
@@ -4994,6 +5070,7 @@ static int ath11k_mac_inc_num_stations(struct ath11k_vif *arvif,
 		return -ENOBUFS;
 
 	ar->num_stations++;
+	arvif->num_stations++;
 
 	return 0;
 }
@@ -5009,6 +5086,7 @@ static void ath11k_mac_dec_num_stations(struct ath11k_vif *arvif,
 		return;
 
 	ar->num_stations--;
+	arvif->num_stations--;
 }
 
 static u32 ath11k_mac_ieee80211_sta_bw_to_wmi(struct ath11k *ar,
@@ -9540,6 +9618,21 @@ static int ath11k_mac_station_add(struct ath11k *ar,
 		goto exit;
 	}
 
+	/* Driver allows the DEL KEY followed by SET KEY sequence for
+	 * group keys for only when there is no clients associated, if at
+	 * all firmware has entered the race during that window,
+	 * reinstalling the same key when the first sta connects will allow
+	 * firmware to recover from the race.
+	 */
+	if (arvif->num_stations == 1 && arvif->reinstall_group_keys) {
+		ath11k_dbg(ab, ATH11K_DBG_MAC, "set group keys on 1st station add for vdev %d\n",
+			   arvif->vdev_id);
+		ret = ath11k_set_group_keys(arvif);
+		if (ret)
+			goto dec_num_station;
+		arvif->reinstall_group_keys = false;
+	}
+
 	arsta->rx_stats = kzalloc(sizeof(*arsta->rx_stats), GFP_KERNEL);
 	if (!arsta->rx_stats) {
 		ret = -ENOMEM;