mac80211: fix num_mcast_sta counting issues

Moving a STA to an AP VLAN prevents num_mcast_sta from being decremented
once the STA leaves, because sta->sdata changes. Fix this by checking
for AP VLANs as well.

Also exclude 4-addr VLAN stations from num_mcast_sta - remote 4-addr
stations ignore 3-address multicast frames anyway. In a typical bridge
configuration they receive the same packets as 4-address unicast.

This patch also fixes clearing the sdata->u.vlan.sta pointer when the
STA is removed from a 4-addr VLAN.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 4c04eb5e4cae..97a9d6639fb9 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -1417,15 +1417,19 @@ int sta_info_move_state(struct sta_info *sta,
                 if (sta->sta_state == IEEE80211_STA_AUTH) {
                         set_bit(WLAN_STA_ASSOC, &sta->_flags);
                 } else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
-                        if (sta->sdata->vif.type == NL80211_IFTYPE_AP)
-                                atomic_dec(&sta->sdata->u.ap.num_mcast_sta);
+                        if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
+                            (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
+                             !sta->sdata->u.vlan.sta))
+                                atomic_dec(&sta->sdata->bss->num_mcast_sta);
                         clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
                 }
                 break;
         case IEEE80211_STA_AUTHORIZED:
                 if (sta->sta_state == IEEE80211_STA_ASSOC) {
-                        if (sta->sdata->vif.type == NL80211_IFTYPE_AP)
-                                atomic_inc(&sta->sdata->u.ap.num_mcast_sta);
+                        if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
+                            (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
+                             !sta->sdata->u.vlan.sta))
+                                atomic_inc(&sta->sdata->bss->num_mcast_sta);
                         set_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
                 }
                 break;