Fixed len for TTL_EXCEEDED icmp packet

Author: danielinux

src/wolfip.c

@@ -1069,15 +1069,18 @@ static void wolfIP_send_ttl_exceeded(struct wolfIP *s, unsigned int if_idx, stru
     struct wolfIP_ll_dev *ll = wolfIP_ll_at(s, if_idx);
     struct wolfIP_icmp_ttl_exceeded_packet icmp;
     struct wolfIP_icmp_packet *icmp_pkt = (struct wolfIP_icmp_packet *)&icmp;
+    uint16_t copy_len;
 #if !CONFIG_IPFILTER
     (void)icmp_pkt;
 #endif
     if (!ll || !ll->send)
         return;
     memset(&icmp, 0, sizeof(icmp));
     icmp.type = ICMP_TTL_EXCEEDED;
-    memcpy(icmp.orig_packet, ((uint8_t *)orig) + ETH_HEADER_LEN,
-            TTL_EXCEEDED_ORIG_PACKET_SIZE);
+    copy_len = ee16(orig->len);
+    if (copy_len > TTL_EXCEEDED_ORIG_PACKET_SIZE)
+        copy_len = TTL_EXCEEDED_ORIG_PACKET_SIZE;
+    memcpy(icmp.orig_packet, ((uint8_t *)orig) + ETH_HEADER_LEN, copy_len);
     icmp.csum = ee16(icmp_checksum((struct wolfIP_icmp_packet *)&icmp,
                 ICMP_TTL_EXCEEDED_SIZE));
     icmp.ip.ver_ihl = 0x45;