Commit 2176d5d4 authored May 09, 2014 by Duan Jiong Committed by David S. Miller May 13, 2014

neigh: set nud_state to NUD_INCOMPLETE when probing router reachability

Since commit 7e980569("ipv6: router reachability probing"), a router falls
into NUD_FAILED will be probed.

Now if function rt6_select() selects a router which neighbour state is NUD_FAILED,
and at the same time function rt6_probe() changes the neighbour state to NUD_PROBE,
then function dst_neigh_output() can directly send packets, but actually the
neighbour still is unreachable. If we set nud_state to NUD_INCOMPLETE instead
NUD_PROBE, packets will not be sent out until the neihbour is reachable.

In addition, because the route should be probes with a single NS, so we must
set neigh->probes to neigh_max_probes(), then the neigh timer timeout and function
neigh_timer_handler() will not send other NS Messages.

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

parent c8965932

net/core/neighbour.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1248,8 +1248,8 @@ void __neigh_set_probe_once(struct neighbour *neigh)
		neigh->updated = jiffies;
		if (!(neigh->nud_state & NUD_FAILED))
		return;
		neigh->nud_state = NUD_PROBE;
		atomic_set(&neigh->probes, NEIGH_VAR(neigh->parms, UCAST_PROBES));
		neigh->nud_state = NUD_INCOMPLETE;
		atomic_set(&neigh->probes, neigh_max_probes(neigh));
		neigh_add_timer(neigh,
		jiffies + NEIGH_VAR(neigh->parms, RETRANS_TIME));
		}

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