On 10/03/17 02:00, David Ahern wrote:

On 3/7/17 5:46 PM, Robert Shearman wrote:

quoted

@@ -244,24 +245,33 @@ static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb,
 		payload_type = ip_hdr(skb)->version;

 	switch (payload_type) {
-	case MPT_IPV4: {
-		struct iphdr *hdr4 = ip_hdr(skb);
+	case MPT_IPV4:
+		if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
+		    (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
+		     net->mpls.ip_ttl_propagate)) {
+			struct iphdr *hdr4 = ip_hdr(skb);
+
+			csum_replace2(&hdr4->check,
+				      htons(hdr4->ttl << 8),
+				      htons(dec.ttl << 8));
+			hdr4->ttl = dec.ttl;
+		}
 		skb->protocol = htons(ETH_P_IP);
-		csum_replace2(&hdr4->check,
-			      htons(hdr4->ttl << 8),
-			      htons(dec.ttl << 8));
-		hdr4->ttl = dec.ttl;
 		success = true;
 		break;
-	}
-	case MPT_IPV6: {
-		struct ipv6hdr *hdr6 = ipv6_hdr(skb);
+	case MPT_IPV6:
+		if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
+		    (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
+		     net->mpls.ip_ttl_propagate)) {
+			struct ipv6hdr *hdr6 = ipv6_hdr(skb);
+
+			hdr6->hop_limit = dec.ttl;
+		}
 		skb->protocol = htons(ETH_P_IPV6);
-		hdr6->hop_limit = dec.ttl;
 		success = true;
 		break;
-	}

What decrements the TTL if it is not propagated from MPLS to IP?

Good point. Will address in v3.

Thanks,
Rob