From c5a71688e1e56e155fb79b8d699322f4f0793cc8 Mon Sep 17 00:00:00 2001 From: Arik Nemtsov Date: Tue, 19 May 2015 14:36:48 +0300 Subject: [PATCH] mac80211: disconnect TDLS stations on STA CSA When a station does a channel switch, it's not well defined what its TDLS peers would do. Avoid a situation when the local side marks a potentially disconnected peer as a TDLS peer. Keeping peers connected through CSA is doubly problematic with the upcoming TDLS WIDER-BW feature which allows peers to widen the BSS channel. The new channel transitioned-to might not be compatible and would require a re-negotiation anyway. Make sure to disallow new TDLS link during CSA. Signed-off-by: Arik Nemtsov Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/mac80211/mlme.c | 26 ++++++++++++++++++++++++++ net/mac80211/tdls.c | 6 ++++++ 2 files changed, 32 insertions(+) diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 3294666f599c..387fe70ab126 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -1098,6 +1098,24 @@ static void ieee80211_chswitch_timer(unsigned long data) ieee80211_queue_work(&sdata->local->hw, &sdata->u.mgd.chswitch_work); } +static void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata) +{ + struct sta_info *sta; + u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED; + + 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)) + continue; + + ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr, + NL80211_TDLS_TEARDOWN, reason, + GFP_ATOMIC); + } + rcu_read_unlock(); +} + static void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata, u64 timestamp, u32 device_timestamp, @@ -1161,6 +1179,14 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata, return; } + /* + * Drop all TDLS peers - either we disconnect or move to a different + * channel from this point on. There's no telling what our peer will do. + * The TDLS WIDER_BW scenario is also problematic, as peers might now + * have an incompatible wider chandef. + */ + ieee80211_teardown_tdls_peers(sdata); + mutex_lock(&local->mtx); mutex_lock(&local->chanctx_mtx); conf = rcu_dereference_protected(sdata->vif.chanctx_conf, diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c index 8a92a920ff17..75e8e3bba538 100644 --- a/net/mac80211/tdls.c +++ b/net/mac80211/tdls.c @@ -1183,6 +1183,12 @@ int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev, switch (oper) { case NL80211_TDLS_ENABLE_LINK: + if (sdata->vif.csa_active) { + tdls_dbg(sdata, "TDLS: disallow link during CSA\n"); + ret = -EBUSY; + break; + } + rcu_read_lock(); sta = sta_info_get(sdata, peer); if (!sta) {