[PATCH v2 3/3] ipv4: Don't report stale pmtu values to userspace
flat view
STALE5123d
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: 2012-10-08 10:56:59
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
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> --- net/ipv4/route.c | 19 +++++++++++-------- 1 files changed, 11 insertions(+), 8 deletions(-)
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 741df67..132e0df 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c@@ -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))
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1.7.0.4