mac80211: dont try to use existing sta for AP

Clean out some cruft that could use an already existing
sta_info struct -- that case cannot happen. Also, there's
a bug there -- if allocation/insertion fails then it is
possible that we are left in a lingering state where
mac80211 waits for the AP, cfg80211 waits for mac80211,
but the AP has already replied. Since there's no way to
indicate an internal error, pretend there was a timeout,
i.e. that the AP never responded.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 24 insertions, 33 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index a7472c979c63..5174bfc5710d 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -75,6 +75,9 @@ enum rx_mgmt_action {
         /* caller must call cfg80211_send_disassoc() */
         RX_MGMT_CFG80211_DISASSOC,
 
+        /* caller must tell cfg80211 about internal error */
+        RX_MGMT_CFG80211_ASSOC_ERROR,
+
         /* caller must call cfg80211_auth_timeout() & free work */
         RX_MGMT_CFG80211_AUTH_TO,
 
@@ -1479,8 +1482,8 @@ ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
         u8 *pos;
         u32 changed = 0;
-        int i, j;
-        bool have_higher_than_11mbit = false, newsta = false;
+        int i, j, err;
+        bool have_higher_than_11mbit = false;
         u16 ap_ht_cap_flags;
 
         /*
@@ -1542,30 +1545,18 @@ ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         printk(KERN_DEBUG "%s: associated\n", sdata->name);
         ifmgd->aid = aid;
 
-        rcu_read_lock();
-
-        /* Add STA entry for the AP */
-        sta = sta_info_get(sdata, wk->bss->cbss.bssid);
+        sta = sta_info_alloc(sdata, wk->bss->cbss.bssid, GFP_KERNEL);
         if (!sta) {
-                newsta = true;
-
-                rcu_read_unlock();
-
-                sta = sta_info_alloc(sdata, wk->bss->cbss.bssid, GFP_KERNEL);
-                if (!sta) {
-                        printk(KERN_DEBUG "%s: failed to alloc STA entry for"
-                               " the AP\n", sdata->name);
-                        return RX_MGMT_NONE;
-                }
-
-                set_sta_flags(sta, WLAN_STA_AUTH | WLAN_STA_ASSOC |
-                                   WLAN_STA_ASSOC_AP);
-                if (!(ifmgd->flags & IEEE80211_STA_CONTROL_PORT))
-                        set_sta_flags(sta, WLAN_STA_AUTHORIZED);
-
-                rcu_read_lock();
+                printk(KERN_DEBUG "%s: failed to alloc STA entry for"
+                       " the AP\n", sdata->name);
+                return RX_MGMT_CFG80211_ASSOC_ERROR;
         }
 
+        set_sta_flags(sta, WLAN_STA_AUTH | WLAN_STA_ASSOC |
+                           WLAN_STA_ASSOC_AP);
+        if (!(ifmgd->flags & IEEE80211_STA_CONTROL_PORT))
+                set_sta_flags(sta, WLAN_STA_AUTHORIZED);
+
         rates = 0;
         basic_rates = 0;
         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
@@ -1628,18 +1619,14 @@ ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         if (elems.wmm_param)
                 set_sta_flags(sta, WLAN_STA_WME);
 
-        if (newsta) {
-                int err = sta_info_insert(sta);
-                if (err) {
-                        printk(KERN_DEBUG "%s: failed to insert STA entry for"
-                               " the AP (error %d)\n", sdata->name, err);
-                        rcu_read_unlock();
-                        return RX_MGMT_NONE;
-                }
+        err = sta_info_insert(sta);
+        sta = NULL;
+        if (err) {
+                printk(KERN_DEBUG "%s: failed to insert STA entry for"
+                       " the AP (error %d)\n", sdata->name, err);
+                return RX_MGMT_CFG80211_ASSOC_ERROR;
         }
 
-        rcu_read_unlock();
-
         if (elems.wmm_param)
                 ieee80211_sta_wmm_params(local, ifmgd, elems.wmm_param,
                                          elems.wmm_param_len);
@@ -2084,6 +2071,10 @@ static void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
         case RX_MGMT_CFG80211_DEAUTH:
                 cfg80211_send_deauth(sdata->dev, (u8 *)mgmt, skb->len);
                 break;
+        case RX_MGMT_CFG80211_ASSOC_ERROR:
+                /* an internal error -- pretend timeout for now */
+                cfg80211_send_assoc_timeout(sdata->dev, mgmt->bssid);
+                break;
         default:
                 WARN(1, "unexpected: %d", rma);
         }