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| author | Sabrina Dubroca <sd@queasysnail.net> | 2018-10-12 16:22:47 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-10-15 22:18:27 -0700 |
| commit | f547fac624be53ad8b07e9ebca7654a7827ba61b (patch) | |
| tree | e8d39c6b9c62085154052363f89245575ded7282 /net/ipv6 | |
| parent | 64bd9c8135751b561f27edaaffe93d07093f81af (diff) | |
| download | lwn-f547fac624be53ad8b07e9ebca7654a7827ba61b.tar.gz lwn-f547fac624be53ad8b07e9ebca7654a7827ba61b.zip | |
ipv6: rate-limit probes for neighbourless routes
When commit 270972554c91 ("[IPV6]: ROUTE: Add Router Reachability
Probing (RFC4191).") introduced router probing, the rt6_probe() function
required that a neighbour entry existed. This neighbour entry is used to
record the timestamp of the last probe via the ->updated field.
Later, commit 2152caea7196 ("ipv6: Do not depend on rt->n in rt6_probe().")
removed the requirement for a neighbour entry. Neighbourless routes skip
the interval check and are not rate-limited.
This patch adds rate-limiting for neighbourless routes, by recording the
timestamp of the last probe in the fib6_info itself.
Fixes: 2152caea7196 ("ipv6: Do not depend on rt->n in rt6_probe().")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/route.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index a366c05a239d..abcb5ae77319 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -520,10 +520,11 @@ static void rt6_probe_deferred(struct work_struct *w) static void rt6_probe(struct fib6_info *rt) { - struct __rt6_probe_work *work; + struct __rt6_probe_work *work = NULL; const struct in6_addr *nh_gw; struct neighbour *neigh; struct net_device *dev; + struct inet6_dev *idev; /* * Okay, this does not seem to be appropriate @@ -539,15 +540,12 @@ static void rt6_probe(struct fib6_info *rt) nh_gw = &rt->fib6_nh.nh_gw; dev = rt->fib6_nh.nh_dev; rcu_read_lock_bh(); + idev = __in6_dev_get(dev); neigh = __ipv6_neigh_lookup_noref(dev, nh_gw); if (neigh) { - struct inet6_dev *idev; - if (neigh->nud_state & NUD_VALID) goto out; - idev = __in6_dev_get(dev); - work = NULL; write_lock(&neigh->lock); if (!(neigh->nud_state & NUD_VALID) && time_after(jiffies, @@ -557,11 +555,13 @@ static void rt6_probe(struct fib6_info *rt) __neigh_set_probe_once(neigh); } write_unlock(&neigh->lock); - } else { + } else if (time_after(jiffies, rt->last_probe + + idev->cnf.rtr_probe_interval)) { work = kmalloc(sizeof(*work), GFP_ATOMIC); } if (work) { + rt->last_probe = jiffies; INIT_WORK(&work->work, rt6_probe_deferred); work->target = *nh_gw; dev_hold(dev); |