ipv4: fix reply_dst leakage on arp reply

There are cases when the created metadata reply is not used. Ensure the
allocated memory is freed also in such cases.

Fixes: 63d008a4e9ee ("ipv4: send arp replies to the correct tunnel")
Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index f03db8b7abee68806468c104470da4054a8bf755..0c9c3482e41997a671c23be7dc0387edb1403916 100644 (file)
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -312,7 +312,7 @@ static void arp_send_dst(int type, int ptype, __be32 dest_ip,
        if (!skb)
                return;
 
-       skb_dst_set(skb, dst);
+       skb_dst_set(skb, dst_clone(dst));
        arp_xmit(skb);
 }
 
@@ -384,7 +384,7 @@ static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb)
        }
 
        if (skb && !(dev->priv_flags & IFF_XMIT_DST_RELEASE))
-               dst = dst_clone(skb_dst(skb));
+               dst = skb_dst(skb);
        arp_send_dst(ARPOP_REQUEST, ETH_P_ARP, target, dev, saddr,
                     dst_hw, dev->dev_addr, NULL, dst);
 }
@@ -811,7 +811,7 @@ static int arp_process(struct sock *sk, struct sk_buff *skb)
                                } else {
                                        pneigh_enqueue(&arp_tbl,
                                                       in_dev->arp_parms, skb);
-                                       return 0;
+                                       goto out_free_dst;
                                }
                                goto out;
                        }
@@ -865,6 +865,8 @@ static int arp_process(struct sock *sk, struct sk_buff *skb)
 
 out:
        consume_skb(skb);
+out_free_dst:
+       dst_release(reply_dst);
        return 0;
 }