diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 089c741..65ed5cd 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -538,8 +538,11 @@
 	if (sk == NULL)
 		return;
 
-	if (type == ICMPV6_PKT_TOOBIG)
+	if (type == ICMPV6_PKT_TOOBIG) {
+		if (!ip6_sk_accept_pmtu(sk))
+			goto out;
 		ip6_sk_update_pmtu(skb, sk, info);
+	}
 	if (type == NDISC_REDIRECT) {
 		ip6_sk_redirect(skb, sk);
 		goto out;