ipv4: Don't report stale pmtu values to userspace

We report cached pmtu values even if they are already expired.
Change this to not report these values after they are expired
and fix a race in the expire time calculation, as suggested by
Eric Dumazet.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Steffen Klassert 2012-10-08 00:56:54 +00:00 коммит произвёл David S. Miller
Родитель 7f92d334ba
Коммит ee9a8f7ab2
1 изменённых файлов: 11 добавлений и 8 удалений

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@ -2187,8 +2187,18 @@ static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway))
goto nla_put_failure;
expires = rt->dst.expires;
if (expires) {
unsigned long now = jiffies;
if (time_before(now, expires))
expires -= now;
else
expires = 0;
}
memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
if (rt->rt_pmtu)
if (rt->rt_pmtu && expires)
metrics[RTAX_MTU - 1] = rt->rt_pmtu;
if (rtnetlink_put_metrics(skb, metrics) < 0)
goto nla_put_failure;
@ -2198,13 +2208,6 @@ static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
goto nla_put_failure;
error = rt->dst.error;
expires = rt->dst.expires;
if (expires) {
if (time_before(jiffies, expires))
expires -= jiffies;
else
expires = 0;
}
if (rt_is_input_route(rt)) {
if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))