net: fix setting of skb->tail in skb_recycle_check()

Since skb_reset_tail_pointer() reads skb->data, we need to set
skb->data before calling skb_reset_tail_pointer().  This was causing
spurious skb_over_panic()s from skb_put() being called on a recycled
skb that had its skb->tail set to beyond where it should have been.

Bug report from Peter van Valderen <linux@ddcrew.com>.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/skbuff.c

@@ -486,8 +486,8 @@ int skb_recycle_check(struct sk_buff *skb, int skb_size)
 	shinfo->frag_list = NULL;
 
 	memset(skb, 0, offsetof(struct sk_buff, tail));
-	skb_reset_tail_pointer(skb);
 	skb->data = skb->head + NET_SKB_PAD;
+	skb_reset_tail_pointer(skb);
 
 	return 1;
 }