route: Fix caught BUG_ON during rt_secret_rebuild_oneshot()

[ Upstream commit 858a18a6a2f74e8f0e5b2e9671d4b74694aba708 ]

route: Fix caught BUG_ON during rt_secret_rebuild_oneshot()

Call rt_secret_rebuild can cause BUG_ON(timer_pending(&net->ipv4.rt_secret_timer)) in
add_timer as there is not any synchronization for call rt_secret_rebuild_oneshot()
for the same net namespace.

Also this issue affects to rt_secret_reschedule().

Thus use mod_timer enstead.

Signed-off-by: Vitaliy Gusev <vgusev@openvz.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index d62b05d33384081b2a5e696f3e68f96967cf5595..555d27873e03ee65d601306dae8db5172c7959e9 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -922,10 +922,8 @@ static void rt_secret_rebuild_oneshot(struct net *net)
 {
        del_timer_sync(&net->ipv4.rt_secret_timer);
        rt_cache_invalidate(net);
-       if (ip_rt_secret_interval) {
-               net->ipv4.rt_secret_timer.expires += ip_rt_secret_interval;
-               add_timer(&net->ipv4.rt_secret_timer);
-       }
+       if (ip_rt_secret_interval)
+               mod_timer(&net->ipv4.rt_secret_timer, jiffies + ip_rt_secret_interval);
 }
 
 static void rt_emergency_hash_rebuild(struct net *net)
@@ -3072,22 +3070,20 @@ static void rt_secret_reschedule(int old)
        rtnl_lock();
        for_each_net(net) {
                int deleted = del_timer_sync(&net->ipv4.rt_secret_timer);
+               long time;
 
                if (!new)
                        continue;
 
                if (deleted) {
-                       long time = net->ipv4.rt_secret_timer.expires - jiffies;
+                       time = net->ipv4.rt_secret_timer.expires - jiffies;
 
                        if (time <= 0 || (time += diff) <= 0)
                                time = 0;
-
-                       net->ipv4.rt_secret_timer.expires = time;
                } else
-                       net->ipv4.rt_secret_timer.expires = new;
+                       time = new;
 
-               net->ipv4.rt_secret_timer.expires += jiffies;
-               add_timer(&net->ipv4.rt_secret_timer);
+               mod_timer(&net->ipv4.rt_secret_timer, jiffies + time);
        }
        rtnl_unlock();
 }