src/lwip/patches/nd6_lladdr_fix.patch

diff --git a/src/core/ipv6/nd6.c b/src/core/ipv6/nd6.c
index 55b5774f..8559d69b 100644
--- a/src/core/ipv6/nd6.c
+++ b/src/core/ipv6/nd6.c
@@ -686,14 +686,15 @@ nd6_input(struct pbuf *p, struct netif *inp)
       switch (option_type) {
       case ND6_OPTION_TYPE_SOURCE_LLADDR:
       {
-        struct lladdr_option *lladdr_opt;
-        if (option_len < (ND6_LLADDR_OPTION_MIN_LENGTH + inp->hwaddr_len)) {
+        const u8_t option_type_and_length_size = 1 + 1;
+        const u8_t *addr_cursor;
+        if (option_len < (option_type_and_length_size + inp->hwaddr_len)) {
           goto lenerr_drop_free_return;
         }
-        lladdr_opt = (struct lladdr_option *)buffer;
+        addr_cursor = buffer + option_type_and_length_size;
         if ((default_router_list[i].neighbor_entry != NULL) &&
             (default_router_list[i].neighbor_entry->state == ND6_INCOMPLETE)) {
-          SMEMCPY(default_router_list[i].neighbor_entry->lladdr, lladdr_opt->addr, inp->hwaddr_len);
+          SMEMCPY(default_router_list[i].neighbor_entry->lladdr, addr_cursor, inp->hwaddr_len);
           default_router_list[i].neighbor_entry->state = ND6_REACHABLE;
           default_router_list[i].neighbor_entry->counter.reachable_time = reachable_time;
         }