1 files changed, 8 insertions, 1 deletions

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 471ed24aabae..14ecdaf06bf7 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1218,7 +1218,14 @@ static void ndisc_router_discovery(struct sk_buff *skb)
         if (rt)
                 rt6_set_expires(rt, jiffies + (HZ * lifetime));
         if (ra_msg->icmph.icmp6_hop_limit) {
-                in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+                /* Only set hop_limit on the interface if it is higher than
+                 * the current hop_limit.
+                 */
+                if (in6_dev->cnf.hop_limit < ra_msg->icmph.icmp6_hop_limit) {
+                        in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+                } else {
+                        ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than current\n");
+                }
                 if (rt)
                         dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
                                        ra_msg->icmph.icmp6_hop_limit);