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| author | Erik Kline <ek@google.com> | 2015-05-18 19:44:41 +0900 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-05-21 16:52:17 -0400 |
| commit | 765c9c639fbb132af0cafc6e1da22fe6cea26bb8 (patch) | |
| tree | 3a197a9708a23ffafcee827225366c8f3ecbbe49 /net/core | |
| parent | 06b2c61c92a9942769ee8da22d3ce8b8b935c038 (diff) | |
| download | linux-765c9c639fbb132af0cafc6e1da22fe6cea26bb8.tar.bz2 | |
neigh: Better handling of transition to NUD_PROBE state
[1] When entering NUD_PROBE state via neigh_update(), perhaps received
from userspace, correctly (re)initialize the probes count to zero.
This is useful for forcing revalidation of a neighbor (for example
if the host is attempting to do DNA [IPv4 4436, IPv6 6059]).
[2] Notify listeners when a neighbor goes into NUD_PROBE state.
By sending notifications on entry to NUD_PROBE state listeners get
more timely warnings of imminent connectivity issues.
The current notifications on entry to NUD_STALE have somewhat
limited usefulness: NUD_STALE is a perfectly normal state, as is
NUD_DELAY, whereas notifications on entry to NUD_FAILURE come after
a neighbor reachability problem has been confirmed (typically after
three probes).
Signed-off-by: Erik Kline <ek@google.com>
Acked-By: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/neighbour.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 3de654256028..3a74df750af4 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -913,6 +913,7 @@ static void neigh_timer_handler(unsigned long arg) neigh->nud_state = NUD_PROBE; neigh->updated = jiffies; atomic_set(&neigh->probes, 0); + notify = 1; next = now + NEIGH_VAR(neigh->parms, RETRANS_TIME); } } else { @@ -1144,6 +1145,8 @@ int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, if (new != old) { neigh_del_timer(neigh); + if (new & NUD_PROBE) + atomic_set(&neigh->probes, 0); if (new & NUD_IN_TIMER) neigh_add_timer(neigh, (jiffies + ((new & NUD_REACHABLE) ? |