From f84eaa1068315409ffbef57e6fea312180787db3 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 12 Mar 2015 08:53:26 +0200 Subject: [PATCH] mac80211: ignore CSA to same channel If the AP is confused and starts doing a CSA to the same channel, just ignore that request instead of trying to act it out since it was likely sent in error anyway. In the case of the bug I was investigating the GO was misbehaving and sending out a beacon with CSA IEs still included after having actually done the channel switch. Signed-off-by: Johannes Berg --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/mlme.c | 13 +++++++++++++ 2 files changed, 14 insertions(+) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index c0e089c194f1..8d53d65bd2ab 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -464,6 +464,7 @@ struct ieee80211_if_managed { unsigned int flags; bool csa_waiting_bcn; + bool csa_ignored_same_chan; bool beacon_crc_valid; u32 beacon_crc; diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index cde8cd3d6595..142f66aece18 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -1150,6 +1150,17 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata, return; } + if (cfg80211_chandef_identical(&csa_ie.chandef, + &sdata->vif.bss_conf.chandef)) { + if (ifmgd->csa_ignored_same_chan) + return; + sdata_info(sdata, + "AP %pM tries to chanswitch to same channel, ignore\n", + ifmgd->associated->bssid); + ifmgd->csa_ignored_same_chan = true; + return; + } + mutex_lock(&local->mtx); mutex_lock(&local->chanctx_mtx); conf = rcu_dereference_protected(sdata->vif.chanctx_conf, @@ -1210,6 +1221,7 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata, sdata->vif.csa_active = true; sdata->csa_chandef = csa_ie.chandef; sdata->csa_block_tx = csa_ie.mode; + ifmgd->csa_ignored_same_chan = false; if (sdata->csa_block_tx) ieee80211_stop_vif_queues(local, sdata, @@ -2090,6 +2102,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata, sdata->vif.csa_active = false; ifmgd->csa_waiting_bcn = false; + ifmgd->csa_ignored_same_chan = false; if (sdata->csa_block_tx) { ieee80211_wake_vif_queues(local, sdata, IEEE80211_QUEUE_STOP_REASON_CSA); -- 2.30.2