1 files changed, 31 insertions, 6 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index c45658309472..091ac0d634a5 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -314,31 +314,46 @@ int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
 }
 
 /* Exported duration function for driver use */
-__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw,
+__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, int if_id,
                                         size_t frame_len, int rate)
 {
         struct ieee80211_local *local = hw_to_local(hw);
+        struct net_device *bdev = dev_get_by_index(if_id);
+        struct ieee80211_sub_if_data *sdata;
         u16 dur;
         int erp;
 
+        if (unlikely(!bdev))
+                return 0;
+
+        sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
         erp = ieee80211_is_erp_rate(hw->conf.phymode, rate);
         dur = ieee80211_frame_duration(local, frame_len, rate,
-                                       erp, local->short_preamble);
+                                       erp, sdata->short_preamble);
 
+        dev_put(bdev);
         return cpu_to_le16(dur);
 }
 EXPORT_SYMBOL(ieee80211_generic_frame_duration);
 
-__le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
+__le16 ieee80211_rts_duration(struct ieee80211_hw *hw, int if_id,
                               size_t frame_len,
                               const struct ieee80211_tx_control *frame_txctl)
 {
         struct ieee80211_local *local = hw_to_local(hw);
         struct ieee80211_rate *rate;
-        int short_preamble = local->short_preamble;
+        struct net_device *bdev = dev_get_by_index(if_id);
+        struct ieee80211_sub_if_data *sdata;
+        int short_preamble;
         int erp;
         u16 dur;
 
+        if (unlikely(!bdev))
+                return 0;
+
+        sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
+        short_preamble = sdata->short_preamble;
+
         rate = frame_txctl->rts_rate;
         erp = !!(rate->flags & IEEE80211_RATE_ERP);
 
@@ -352,20 +367,29 @@ __le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
         dur += ieee80211_frame_duration(local, 10, rate->rate,
                                         erp, short_preamble);
 
+        dev_put(bdev);
         return cpu_to_le16(dur);
 }
 EXPORT_SYMBOL(ieee80211_rts_duration);
 
-__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
+__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, int if_id,
                                     size_t frame_len,
                                     const struct ieee80211_tx_control *frame_txctl)
 {
         struct ieee80211_local *local = hw_to_local(hw);
         struct ieee80211_rate *rate;
-        int short_preamble = local->short_preamble;
+        struct net_device *bdev = dev_get_by_index(if_id);
+        struct ieee80211_sub_if_data *sdata;
+        int short_preamble;
         int erp;
         u16 dur;
 
+        if (unlikely(!bdev))
+                return 0;
+
+        sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
+        short_preamble = sdata->short_preamble;
+
         rate = frame_txctl->rts_rate;
         erp = !!(rate->flags & IEEE80211_RATE_ERP);
 
@@ -378,6 +402,7 @@ __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
                                                 erp, short_preamble);
         }
 
+        dev_put(bdev);
         return cpu_to_le16(dur);
 }
 EXPORT_SYMBOL(ieee80211_ctstoself_duration);