From a960ff81f0cd6390940faa75a078ac76acec7940 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
Date: Wed, 26 Feb 2014 11:43:04 +0200
Subject: [PATCH] neigh: probe application via netlink in NUD_PROBE
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
iproute2 arpd seems to expect this as there's code and comments
to handle netlink probes with NUD_PROBE set. It is used to flush
the arpd cached mappings.
opennhrp instead turns off unicast probes (so it can handle all
neighbour discovery). Without this change it will not see NUD_PROBE
probes and cannot reconfirm the mapping. Thus currently neigh entry
will just fail and can cause few packets dropped until broadcast
discovery is restarted.
Earlier discussion on the subject:
http://marc.info/?t=139305877100001&r=1&w=2
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/core/neighbour.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index b9e9e0d38672..36d3f8c1a2dd 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -836,10 +836,10 @@ static void neigh_periodic_work(struct work_struct *work)
static __inline__ int neigh_max_probes(struct neighbour *n)
{
struct neigh_parms *p = n->parms;
- return (n->nud_state & NUD_PROBE) ?
- NEIGH_VAR(p, UCAST_PROBES) :
- NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES) +
- NEIGH_VAR(p, MCAST_PROBES);
+ int max_probes = NEIGH_VAR(p, UCAST_PROBES) + NEIGH_VAR(p, APP_PROBES);
+ if (!(n->nud_state & NUD_PROBE))
+ max_probes += NEIGH_VAR(p, MCAST_PROBES);
+ return max_probes;
}
static void neigh_invalidate(struct neighbour *neigh)
--
GitLab