1 files changed, 41 insertions, 9 deletions

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 1b4a4a953675..366fbba3359a 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -478,14 +478,44 @@ static void ipip6_tunnel_uninit(struct net_device *dev)
         dev_put(dev);
 }
 
+/* Generate icmpv6 with type/code ICMPV6_DEST_UNREACH/ICMPV6_ADDR_UNREACH
+ * if sufficient data bytes are available
+ */
+static int ipip6_err_gen_icmpv6_unreach(struct sk_buff *skb)
+{
+        const struct iphdr *iph = (const struct iphdr *) skb->data;
+        struct rt6_info *rt;
+        struct sk_buff *skb2;
+
+        if (!pskb_may_pull(skb, iph->ihl * 4 + sizeof(struct ipv6hdr) + 8))
+                return 1;
+
+        skb2 = skb_clone(skb, GFP_ATOMIC);
+
+        if (!skb2)
+                return 1;
+
+        skb_dst_drop(skb2);
+        skb_pull(skb2, iph->ihl * 4);
+        skb_reset_network_header(skb2);
+
+        rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, NULL, 0, 0);
+
+        if (rt && rt->dst.dev)
+                skb2->dev = rt->dst.dev;
+
+        icmpv6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
+
+        if (rt)
+                ip6_rt_put(rt);
+
+        kfree_skb(skb2);
+
+        return 0;
+}
 
 static int ipip6_err(struct sk_buff *skb, u32 info)
 {
-
-/* All the routers (except for Linux) return only
-   8 bytes of packet payload. It means, that precise relaying of
-   ICMP in the real Internet is absolutely infeasible.
- */
         const struct iphdr *iph = (const struct iphdr *)skb->data;
         const int type = icmp_hdr(skb)->type;
         const int code = icmp_hdr(skb)->code;
@@ -500,7 +530,6 @@ static int ipip6_err(struct sk_buff *skb, u32 info)
         case ICMP_DEST_UNREACH:
                 switch (code) {
                 case ICMP_SR_FAILED:
-                case ICMP_PORT_UNREACH:
                         /* Impossible event. */
                         return 0;
                 default:
@@ -545,6 +574,9 @@ static int ipip6_err(struct sk_buff *skb, u32 info)
                 goto out;
 
         err = 0;
+        if (!ipip6_err_gen_icmpv6_unreach(skb))
+                goto out;
+
         if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
                 goto out;
 
@@ -919,7 +951,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
                 if (!new_skb) {
                         ip_rt_put(rt);
                         dev->stats.tx_dropped++;
-                        dev_kfree_skb(skb);
+                        kfree_skb(skb);
                         return NETDEV_TX_OK;
                 }
                 if (skb->sk)
@@ -945,7 +977,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
 tx_error_icmp:
         dst_link_failure(skb);
 tx_error:
-        dev_kfree_skb(skb);
+        kfree_skb(skb);
 out:
         dev->stats.tx_errors++;
         return NETDEV_TX_OK;
@@ -985,7 +1017,7 @@ static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
 
 tx_err:
         dev->stats.tx_errors++;
-        dev_kfree_skb(skb);
+        kfree_skb(skb);
         return NETDEV_TX_OK;
 
 }