[IPv4]: Reply net unreachable ICMP message

IPv4 stack doesn't reply any ICMP destination unreachable message
with net unreachable code when IP detagrams are being discarded
because of no route could be found in the forwarding path.
Incidentally, IPv6 stack replies such ICMPv6 message in the similar
situation.

Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index c426dec6d57903467fd5cd7a233a872efa0524ce..79c4b9360a12a3e1564bc1ded880a5534f08522a 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1252,6 +1252,7 @@ static int ip_error(struct sk_buff *skb)
                        break;
                case ENETUNREACH:
                        code = ICMP_NET_UNREACH;
+                       IP_INC_STATS_BH(IPSTATS_MIB_INNOROUTES);
                        break;
                case EACCES:
                        code = ICMP_PKT_FILTERED;
@@ -1881,6 +1882,8 @@ no_route:
        RT_CACHE_STAT_INC(in_no_route);
        spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
        res.type = RTN_UNREACHABLE;
+       if (err == -ESRCH)
+               err = -ENETUNREACH;
        goto local_input;
 
        /*