[PATCH 4.19 031/243] iwlwifi: mvm: Send non offchannel traffic via AP sta

From: Greg Kroah-Hartman
Date: Wed Dec 11 2019 - 10:54:04 EST


From: Andrei Otcheretianski <andrei.otcheretianski@xxxxxxxxx>

[ Upstream commit dc1aca22f8f38b7e2ad7b118db87404d11e68771 ]

TDLS discovery response frame is a unicast direct frame to the peer.
Since we don't have a STA for this peer, this frame goes through
iwl_tx_skb_non_sta(). As the result aux_sta and some completely
arbitrary queue would be selected for this frame, resulting in a queue
hang. Fix that by sending such frames through AP sta instead.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index 0f357e8c4f940..476c44db0e64b 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -820,6 +820,21 @@ static void iwl_mvm_mac_tx(struct ieee80211_hw *hw,
!ieee80211_is_bufferable_mmpdu(hdr->frame_control))
sta = NULL;

+ /* If there is no sta, and it's not offchannel - send through AP */
+ if (info->control.vif->type == NL80211_IFTYPE_STATION &&
+ info->hw_queue != IWL_MVM_OFFCHANNEL_QUEUE && !sta) {
+ struct iwl_mvm_vif *mvmvif =
+ iwl_mvm_vif_from_mac80211(info->control.vif);
+ u8 ap_sta_id = READ_ONCE(mvmvif->ap_sta_id);
+
+ if (ap_sta_id < IWL_MVM_STATION_COUNT) {
+ /* mac80211 holds rcu read lock */
+ sta = rcu_dereference(mvm->fw_id_to_mac_id[ap_sta_id]);
+ if (IS_ERR_OR_NULL(sta))
+ goto drop;
+ }
+ }
+
if (sta) {
if (iwl_mvm_defer_tx(mvm, sta, skb))
return;
--
2.20.1