mac80211: call get_expected_throughput only after adding station

Depending on which method the driver implements, userspace could
call this (indirectly, by getting station info) before the driver
knows about the station, possibly causing it to misbehave.

Therefore, add a check for sta->uploaded which indicates that the
driver knows about the station.
Signed-off-by: Maxim Altshul <maxim.altshul@ti.com>
[reword commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/driver-ops.h

@@ -1088,13 +1088,13 @@ static inline void drv_leave_ibss(struct ieee80211_local *local,
 }
 
 static inline u32 drv_get_expected_throughput(struct ieee80211_local *local,
-					      struct ieee80211_sta *sta)
+					      struct sta_info *sta)
 {
 	u32 ret = 0;
 
-	trace_drv_get_expected_throughput(sta);
-	if (local->ops->get_expected_throughput)
-		ret = local->ops->get_expected_throughput(&local->hw, sta);
+	trace_drv_get_expected_throughput(&sta->sta);
+	if (local->ops->get_expected_throughput && sta->uploaded)
+		ret = local->ops->get_expected_throughput(&local->hw, &sta->sta);
 	trace_drv_return_u32(local, ret);
 
 	return ret;

net/mac80211/sta_info.c

@@ -2301,7 +2301,7 @@ u32 sta_get_expected_throughput(struct sta_info *sta)
 	if (ref && ref->ops->get_expected_throughput)
 		thr = ref->ops->get_expected_throughput(sta->rate_ctrl_priv);
 	else
-		thr = drv_get_expected_throughput(local, &sta->sta);
+		thr = drv_get_expected_throughput(local, sta);
 
 	return thr;
 }