package/kernel/mac80211/patches/392-mac80211-don-t-Tx-a-deauth-frame-if-the-AP-forbade-T.patch

   1 From: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
   2 Date: Fri, 31 Aug 2018 11:31:12 +0300
   3 Subject: [PATCH] mac80211: don't Tx a deauth frame if the AP forbade Tx
   4
   5 If the driver fails to properly prepare for the channel
   6 switch, mac80211 will disconnect. If the CSA IE had mode
   7 set to 1, it means that the clients are not allowed to send
   8 any Tx on the current channel, and that includes the
   9 deauthentication frame.
  10
  11 Make sure that we don't send the deauthentication frame in
  12 this case.
  13
  14 In iwlwifi, this caused a failure to flush queues since the
  15 firmware already closed the queues after having parsed the
  16 CSA IE. Then mac80211 would wait until the deauthentication
  17 frame would go out (drv_flush(drop=false)) and that would
  18 never happen.
  19
  20 Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
  21 Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
  22 Signed-off-by: Johannes Berg <johannes.berg@intel.com>
  23 ---
  24
  25 --- a/net/mac80211/mlme.c
  26 +++ b/net/mac80211/mlme.c
  27 @@ -1267,6 +1267,16 @@ ieee80211_sta_process_chanswitch(struct
  28                                          cbss->beacon_interval));
  29         return;
  30   drop_connection:
  31 +       /*
  32 +        * This is just so that the disconnect flow will know that
  33 +        * we were trying to switch channel and failed. In case the
  34 +        * mode is 1 (we are not allowed to Tx), we will know not to
  35 +        * send a deauthentication frame. Those two fields will be
  36 +        * reset when the disconnection worker runs.
  37 +        */
  38 +       sdata->vif.csa_active = true;
  39 +       sdata->csa_block_tx = csa_ie.mode;
  40 +
  41         ieee80211_queue_work(&local->hw, &ifmgd->csa_connection_drop_work);
  42         mutex_unlock(&local->chanctx_mtx);
  43         mutex_unlock(&local->mtx);
  44 @@ -2437,6 +2447,7 @@ static void __ieee80211_disconnect(struc
  45         struct ieee80211_local *local = sdata->local;
  46         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
  47         u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
  48 +       bool tx;
  49
  50         sdata_lock(sdata);
  51         if (!ifmgd->associated) {
  52 @@ -2444,6 +2455,8 @@ static void __ieee80211_disconnect(struc
  53                 return;
  54         }
  55
  56 +       tx = !sdata->csa_block_tx;
  57 +
  58         /* AP is probably out of range (or not reachable for another reason) so
  59          * remove the bss struct for that AP.
  60          */
  61 @@ -2451,7 +2464,7 @@ static void __ieee80211_disconnect(struc
  62
  63         ieee80211_set_disassoc(sdata, IEEE80211_STYPE_DEAUTH,
  64                                WLAN_REASON_DISASSOC_DUE_TO_INACTIVITY,
  65 -                              true, frame_buf);
  66 +                              tx, frame_buf);
  67         mutex_lock(&local->mtx);
  68         sdata->vif.csa_active = false;
  69         ifmgd->csa_waiting_bcn = false;
  70 @@ -2462,7 +2475,7 @@ static void __ieee80211_disconnect(struc
  71         }
  72         mutex_unlock(&local->mtx);
  73
  74 -       ieee80211_report_disconnect(sdata, frame_buf, sizeof(frame_buf), true,
  75 +       ieee80211_report_disconnect(sdata, frame_buf, sizeof(frame_buf), tx,
  76                                     WLAN_REASON_DISASSOC_DUE_TO_INACTIVITY);
  77
  78         sdata_unlock(sdata);