mac80211: fix ieee80211_get_buffered_bc

fix bss not initialized in ieee80211_get_buffered_bc
and unbalanced locking

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 9 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index dac44cbd036f..16af30811f98 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1947,7 +1947,7 @@ ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
                           struct ieee80211_vif *vif)
 {
         struct ieee80211_local *local = hw_to_local(hw);
-        struct sk_buff *skb;
+        struct sk_buff *skb = NULL;
         struct sta_info *sta;
         ieee80211_tx_handler *handler;
         struct ieee80211_tx_data tx;
@@ -1960,7 +1960,7 @@ ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
 
         sdata = vif_to_sdata(vif);
         bdev = sdata->dev;
-
+        bss = &sdata->u.ap;
 
         if (!bss)
                 return NULL;
@@ -1968,19 +1968,16 @@ ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
         rcu_read_lock();
         beacon = rcu_dereference(bss->beacon);
 
-        if (sdata->vif.type != IEEE80211_IF_TYPE_AP || !beacon ||
-            !beacon->head) {
-                rcu_read_unlock();
-                return NULL;
-        }
+        if (sdata->vif.type != IEEE80211_IF_TYPE_AP || !beacon || !beacon->head)
+                goto out;
 
         if (bss->dtim_count != 0)
-                return NULL; /* send buffered bc/mc only after DTIM beacon */
+                goto out; /* send buffered bc/mc only after DTIM beacon */
 
         while (1) {
                 skb = skb_dequeue(&bss->ps_bc_buf);
                 if (!skb)
-                        return NULL;
+                        goto out;
                 local->total_ps_buffered--;
 
                 if (!skb_queue_empty(&bss->ps_bc_buf) && skb->len >= 2) {
@@ -2023,6 +2020,7 @@ ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
                 skb = NULL;
         }
 
+out:
         rcu_read_unlock();
 
         return skb;