From 70d46d23cd23309a068ee9983dfe7ce074c032dd Mon Sep 17 00:00:00 2001
From: xueyunfei <xueyunfei@espressif.com>
Date: Thu, 30 Apr 2020 16:56:47 +0800
Subject: [PATCH] ip_frag: Drop IPv6 packets larger than MTU

Drop larger packets if ipv6-fragmentation is disabled

Picked from: espressif/esp-lwip@5b2072eb
Ref IDF-4846
---
 src/core/ipv6/ip6.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/core/ipv6/ip6.c b/src/core/ipv6/ip6.c
index 060d5f35..4fc11994 100644
--- a/src/core/ipv6/ip6.c
+++ b/src/core/ipv6/ip6.c
@@ -1263,6 +1263,8 @@ ip6_output_if_src(struct pbuf *p, const ip6_addr_t *src, const ip6_addr_t *dest,
   if (netif_mtu6(netif) && (p->tot_len > nd6_get_destination_mtu(dest, netif))) {
     return ip6_frag(p, netif, dest);
   }
+#else
+  LWIP_ERROR("ip6_output_if: Packet larger than MTU discarded", !(netif->mtu && p->tot_len > netif->mtu), return ERR_IF;);
 #endif /* LWIP_IPV6_FRAG */
 
   LWIP_DEBUGF(IP6_DEBUG, ("netif->output_ip6()\n"));