ipv6 route: Fix route lifetime in netlink message.

1) We may have route lifetime larger than INT_MAX.
In that case we had wired value in lifetime.
Use INT_MAX if lifetime does not fit in s32.

2) Lifetime is valid iif RTF_EXPIRES is set.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 220cffe9e63b..d1f3e19b06c7 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -2196,8 +2196,12 @@ static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
 
         NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
 
-        expires = (rt->rt6i_flags & RTF_EXPIRES) ?
-                        rt->rt6i_expires - jiffies : 0;
+        if (!(rt->rt6i_flags & RTF_EXPIRES))
+                expires = 0;
+        else if (rt->rt6i_expires - jiffies < INT_MAX)
+                expires = rt->rt6i_expires - jiffies;
+        else
+                expires = INT_MAX;
 
         if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
                                expires, rt->u.dst.error) < 0)