mac80211: protect non-HT BSS when HT TDLS traffic exists
HT TDLS traffic should be protected in a non-HT BSS to avoid
collisions. Therefore, when TDLS peers join/leave, check if
protection is (now) needed and set the ht_operation_mode of
the virtual interface according to the HT capabilities of the
TDLS peer(s).
This works because a non-HT BSS connection never sets (or
otherwise uses) the ht_operation_mode; it just means that
drivers must be aware that this field applies to all HT
traffic for this virtual interface, not just the traffic
within the BSS. Document that.
Signed-off-by: Avri Altman <avri.altman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index e3314e5..bfc5694 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -477,7 +477,9 @@
* @chandef: Channel definition for this BSS -- the hardware might be
* configured a higher bandwidth than this BSS uses, for example.
* @ht_operation_mode: HT operation mode like in &struct ieee80211_ht_operation.
- * This field is only valid when the channel type is one of the HT types.
+ * This field is only valid when the channel is a wide HT/VHT channel.
+ * Note that with TDLS this can be the case (channel is HT, protection must
+ * be used from this field) even when the BSS association isn't using HT.
* @cqm_rssi_thold: Connection quality monitor RSSI threshold, a zero value
* implies disabled
* @cqm_rssi_hyst: Connection quality monitor RSSI hysteresis
diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index aee701a..4e202d0 100644
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -1249,6 +1249,58 @@
mutex_unlock(&local->chanctx_mtx);
}
+static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
+{
+ struct sta_info *sta;
+ bool result = false;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
+ if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
+ !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
+ !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
+ !sta->sta.ht_cap.ht_supported)
+ continue;
+ result = true;
+ break;
+ }
+ rcu_read_unlock();
+
+ return result;
+}
+
+static void
+iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta)
+{
+ struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+ bool tdls_ht;
+ u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
+ IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
+ IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
+ u16 opmode;
+
+ /* Nothing to do if the BSS connection uses HT */
+ if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
+ return;
+
+ tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
+ iee80211_tdls_have_ht_peers(sdata);
+
+ opmode = sdata->vif.bss_conf.ht_operation_mode;
+
+ if (tdls_ht)
+ opmode |= protection;
+ else
+ opmode &= ~protection;
+
+ if (opmode == sdata->vif.bss_conf.ht_operation_mode)
+ return;
+
+ sdata->vif.bss_conf.ht_operation_mode = opmode;
+ ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
+}
+
int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
const u8 *peer, enum nl80211_tdls_operation oper)
{
@@ -1274,6 +1326,10 @@
return -ENOTSUPP;
}
+ /* protect possible bss_conf changes and avoid concurrency in
+ * ieee80211_bss_info_change_notify()
+ */
+ sdata_lock(sdata);
mutex_lock(&local->mtx);
tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
@@ -1287,16 +1343,18 @@
iee80211_tdls_recalc_chanctx(sdata);
- rcu_read_lock();
+ mutex_lock(&local->sta_mtx);
sta = sta_info_get(sdata, peer);
if (!sta) {
- rcu_read_unlock();
+ mutex_unlock(&local->sta_mtx);
ret = -ENOLINK;
break;
}
+ iee80211_tdls_recalc_ht_protection(sdata, sta);
+
set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
- rcu_read_unlock();
+ mutex_unlock(&local->sta_mtx);
WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
!ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
@@ -1318,6 +1376,11 @@
ieee80211_flush_queues(local, sdata, false);
ret = sta_info_destroy_addr(sdata, peer);
+
+ mutex_lock(&local->sta_mtx);
+ iee80211_tdls_recalc_ht_protection(sdata, NULL);
+ mutex_unlock(&local->sta_mtx);
+
iee80211_tdls_recalc_chanctx(sdata);
break;
default:
@@ -1335,6 +1398,7 @@
&sdata->u.mgd.request_smps_work);
mutex_unlock(&local->mtx);
+ sdata_unlock(sdata);
return ret;
}