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 <johannes.berg@intel.com>
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index cde8cd3..142f66a 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1150,6 +1150,17 @@
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 @@
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 @@
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);