mac80211 : fix unaligned rx skb

[matthieu castet <castet.matthieu@free.fr>]

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mac80211 is checking is the skb is aligned on 32 bit boundary.
But it is checking against ethernet header, whereas Linux expect IP
header aligned.
And ethernet ether size is 6*2+2=14, so aligning ethernet header make IP header unaligned.

Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 9776f73..0845fb3 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1397,7 +1397,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
 		 * mac80211. That also explains the __skb_push()
 		 * below.
 		 */
-		align = (unsigned long)skb->data & 3;
+		align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
 		if (align) {
 			if (WARN_ON(skb_headroom(skb) < 3)) {
 				dev_kfree_skb(skb);