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: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath9k/xmit.c

@@ -106,6 +106,7 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
 	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 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
 				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);
 }