ath9k: Remove MAC header pad before reporting TX status

Remove the possible MAC header pad before reporting TX status to
mac80211. This pad is hardware specific operation and should not be
exposed outside the driver. This fixes the frame body in monitor
interfaces that could be used to check on TX status for transmitted
frames.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath9k/xmit.c b/drivers/net/wireless/ath9k/xmit.c
index d6d402c..3bfc3b9 100644
--- a/drivers/net/wireless/ath9k/xmit.c
+++ b/drivers/net/wireless/ath9k/xmit.c
@@ -106,6 +106,7 @@
 	struct ieee80211_hw *hw = sc->hw;
 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
 	struct ath_tx_info_priv *tx_info_priv = ATH_TX_INFO_PRIV(tx_info);
+	int hdrlen, padsize;
 
 	DPRINTF(sc, ATH_DBG_XMIT, "TX complete: skb: %p\n", skb);
 
@@ -135,6 +136,17 @@
 				rate_table->info[idx].ratecode & 0x7f;
 	}
 
+	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
+	padsize = hdrlen & 3;
+	if (padsize && hdrlen >= 24) {
+		/*
+		 * Remove MAC header padding before giving the frame back to
+		 * mac80211.
+		 */
+		memmove(skb->data + padsize, skb->data, hdrlen);
+		skb_pull(skb, padsize);
+	}
+
 	ieee80211_tx_status(hw, skb);
 }