[PATCH] IP: Increment INADDRERRORS if routing for a packet is not successful

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
From: Christoph Lameter
Date: Tuesday, June 1, 2010 - 2:13 pm

Something like this would have been very helpful during recent debugging
of multicast issues. Silent discards are bad.


If the kernel perceives that something is wrong with an incoming packet then the
IP stack currently silently discards packets. This makes it difficult to diagnose
problems with the network configurations (such as a misbehaving kernel
subsystem discarding multicast packets because the reverse path filter
does not like multicast subscriptions on the second NIC with rp_filter=1).

It is also necessary to know how many inbound packets are discarded to
assess networking issues in general with a NIC.

Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>

---
 net/ipv4/route.c |    3 +++
 1 file changed, 3 insertions(+)

Index: linux-2.6/net/ipv4/route.c
===================================================================
--- linux-2.6.orig/net/ipv4/route.c	2010-06-01 11:46:10.000000000 -0500
+++ linux-2.6/net/ipv4/route.c	2010-06-01 11:52:55.000000000 -0500
@@ -2981,6 +2981,9 @@ static int inet_rtm_getroute(struct sk_b
 		rt = skb_rtable(skb);
 		if (err == 0 && rt->u.dst.error)
 			err = -rt->u.dst.error;
+		if (err)
+			IP_INC_STATS_BH(dev_net(skb->dev),
+					IPSTATS_MIB_INADDRERRORS);
 	} else {
 		struct flowi fl = {
 			.nl_u = {


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[PATCH] IP: Increment INADDRERRORS if routing for a packet ..., Christoph Lameter, (Tue Jun 1, 2:13 pm)
Re: [PATCH] IP: Increment INADDRERRORS if routing for a pa ..., Christoph Lameter, (Wed Jun 2, 11:01 am)
Re: [PATCH] IP: Increment INADDRERRORS if routing for a pa ..., Christoph Lameter, (Wed Jun 2, 11:59 am)