Commit 8dfd329f authored by Zhang Shengju's avatar Zhang Shengju Committed by David S. Miller
Browse files

arp: correct return value of arp_rcv 



Currently, arp_rcv() always return zero on a packet delivery upcall.

To make its behavior more compliant with the way this API should be
used, this patch changes this to let it return NET_RX_SUCCESS when the
packet is proper handled, and NET_RX_DROP otherwise.

v1->v2:
If sanity check is failed, call kfree_skb() instead of consume_skb(), then
return the correct return value.

Signed-off-by: default avatarZhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8303394d

net/ipv4/arp.c

+20 −15
Original line number Diff line number Diff line
@@ -665,7 +665,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
	 */



	if (!in_dev)

		goto out;

		goto out_free_skb;



	arp = arp_hdr(skb);
@@ -673,7 +673,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
	default:

		if (arp->ar_pro != htons(ETH_P_IP) ||

		    htons(dev_type) != arp->ar_hrd)

			goto out;

			goto out_free_skb;

		break;

	case ARPHRD_ETHER:

	case ARPHRD_FDDI:
@@ -690,17 +690,17 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
		if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&

		     arp->ar_hrd != htons(ARPHRD_IEEE802)) ||

		    arp->ar_pro != htons(ETH_P_IP))

			goto out;

			goto out_free_skb;

		break;

	case ARPHRD_AX25:

		if (arp->ar_pro != htons(AX25_P_IP) ||

		    arp->ar_hrd != htons(ARPHRD_AX25))

			goto out;

			goto out_free_skb;

		break;

	case ARPHRD_NETROM:

		if (arp->ar_pro != htons(AX25_P_IP) ||

		    arp->ar_hrd != htons(ARPHRD_NETROM))

			goto out;

			goto out_free_skb;

		break;

	}
@@ -708,7 +708,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 


	if (arp->ar_op != htons(ARPOP_REPLY) &&

	    arp->ar_op != htons(ARPOP_REQUEST))

		goto out;

		goto out_free_skb;



/*

 *	Extract fields
@@ -733,7 +733,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
 */

	if (ipv4_is_multicast(tip) ||

	    (!IN_DEV_ROUTE_LOCALNET(in_dev) && ipv4_is_loopback(tip)))

		goto out;

		goto out_free_skb;



 /*

  *	For some 802.11 wireless deployments (and possibly other networks),
@@ -741,7 +741,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
  *	and thus should not be accepted.

  */

	if (sip == tip && IN_DEV_ORCONF(in_dev, DROP_GRATUITOUS_ARP))

		goto out;

		goto out_free_skb;



/*

 *     Special case: We must set Frame Relay source Q.922 address
@@ -778,7 +778,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
		    !arp_ignore(in_dev, sip, tip))

			arp_send_dst(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip,

				     sha, dev->dev_addr, sha, reply_dst);

		goto out;

		goto out_consume_skb;

	}



	if (arp->ar_op == htons(ARPOP_REQUEST) &&
@@ -803,7 +803,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
					neigh_release(n);

				}

			}

			goto out;

			goto out_consume_skb;

		} else if (IN_DEV_FORWARD(in_dev)) {

			if (addr_type == RTN_UNICAST  &&

			    (arp_fwd_proxy(in_dev, dev, rt) ||
@@ -826,7 +826,7 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
						       in_dev->arp_parms, skb);

					goto out_free_dst;

				}

				goto out;

				goto out_consume_skb;

			}

		}

	}
@@ -876,11 +876,16 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb) 
		neigh_release(n);

	}



out:

out_consume_skb:

	consume_skb(skb);



out_free_dst:

	dst_release(reply_dst);

	return 0;

	return NET_RX_SUCCESS;



out_free_skb:

	kfree_skb(skb);

	return NET_RX_DROP;

}



static void parp_redo(struct sk_buff *skb)
@@ -924,11 +929,11 @@ static int arp_rcv(struct sk_buff *skb, struct net_device *dev, 


consumeskb:

	consume_skb(skb);

	return 0;

	return NET_RX_SUCCESS;

freeskb:

	kfree_skb(skb);

out_of_mem:

	return 0;

	return NET_RX_DROP;

}



/*

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