Commit 505a41d4 authored Dec 10, 2007 by Julia Lawall Committed by David S. Miller Dec 11, 2007

[UM]: Fix use of skb after netif_rx

Recently, Wang Chen submitted a patch
(d30f53ae) to move a call to netif_rx(skb)
after a subsequent reference to skb, because netif_rx may call kfree_skb on
its argument.  The same problem occurs in some other drivers as well.

This was found using the following semantic match.
(http://www.emn.fr/x-info/coccinelle/

)

// <smpl>
@@
expression skb, e,e1;
@@

(
 netif_rx(skb);
|
 netif_rx_ni(skb);
)
  ... when != skb = e
(
  skb = e1
|
* skb
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 95a02cfd

arch/um/drivers/net_kern.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -98,10 +98,10 @@ static int uml_net_rx(struct net_device *dev)
	if (pkt_len > 0) {		if (pkt_len > 0) {
	skb_trim(skb, pkt_len);		skb_trim(skb, pkt_len);
	skb->protocol = (*lp->protocol)(skb);		skb->protocol = (*lp->protocol)(skb);
	netif_rx(skb);

	lp->stats.rx_bytes += skb->len;		lp->stats.rx_bytes += skb->len;
	lp->stats.rx_packets++;		lp->stats.rx_packets++;
			netif_rx(skb);
	return pkt_len;		return pkt_len;
	}		}