ipv4: distinguish EHOSTUNREACH from the ENETUNREACH

since commit 251da413("ipv4: Cache ip_error() routes even when not forwarding."),
the counter IPSTATS_MIB_INADDRERRORS can't work correctly, because the value of
err was always set to ENETUNREACH.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 2 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 25071b48921c..6f6dd85bdffc 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1695,8 +1695,11 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
         fl4.daddr = daddr;
         fl4.saddr = saddr;
         err = fib_lookup(net, &fl4, &res);
-        if (err != 0)
+        if (err != 0) {
+                if (!IN_DEV_FORWARD(in_dev))
+                        err = -EHOSTUNREACH;
                 goto no_route;
+        }
 
         RT_CACHE_STAT_INC(in_slow_tot);
 
@@ -1712,8 +1715,10 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
                 goto local_input;
         }
 
-        if (!IN_DEV_FORWARD(in_dev))
+        if (!IN_DEV_FORWARD(in_dev)) {
+                err = -EHOSTUNREACH;
                 goto no_route;
+        }
         if (res.type != RTN_UNICAST)
                 goto martian_destination;