diff --git a/app/lwip/core/dns.c b/app/lwip/core/dns.c
index ab6821f2..1fe7aaa4 100644
--- a/app/lwip/core/dns.c
+++ b/app/lwip/core/dns.c
@@ -173,7 +173,7 @@ struct dns_table_entry {
   u8_t  seqno;
   u8_t  err;
   u32_t ttl;
-  char name[DNS_MAX_NAME_LENGTH];
+  char *name;
   ip_addr_t ipaddr;
   /* pointer to callback on DNS query done */
   dns_found_callback found;
@@ -673,6 +673,8 @@ dns_check_entry(u8_t i)
             if (pEntry->found)
               (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
             /* flush this entry */
+            mem_free (pEntry->name);
+            pEntry->name    = NULL;
             pEntry->state   = DNS_STATE_UNUSED;
             pEntry->found   = NULL;
             break;
@@ -697,6 +699,8 @@ dns_check_entry(u8_t i)
       if (--pEntry->ttl == 0) {
         LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": flush\n", pEntry->name));
         /* flush this entry */
+        mem_free (pEntry->name);
+        pEntry->name    = NULL;
         pEntry->state = DNS_STATE_UNUSED;
         pEntry->found = NULL;
       }
@@ -839,6 +843,8 @@ responseerr:
     (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
   }
   /* flush this entry */
+  mem_free (pEntry->name);
+  pEntry->name  = NULL;
   pEntry->state = DNS_STATE_UNUSED;
   pEntry->found = NULL;
 
@@ -898,11 +904,16 @@ dns_enqueue(const char *name, dns_found_callback found, void *callback_arg)
   LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": use DNS entry %"U16_F"\n", name, (u16_t)(i)));
 
   /* fill the entry */
+  namelen = LWIP_MIN(strlen(name), DNS_MAX_NAME_LENGTH-1);
+  char *namebuf = (char *)mem_zalloc (namelen);
+  if (!namebuf)
+    return ERR_MEM;
   pEntry->state = DNS_STATE_NEW;
   pEntry->seqno = dns_seqno++;
   pEntry->found = found;
   pEntry->arg   = callback_arg;
-  namelen = LWIP_MIN(strlen(name), DNS_MAX_NAME_LENGTH-1);
+  mem_free (pEntry->name);
+  pEntry->name = namebuf;
   MEMCPY(pEntry->name, name, namelen);
   pEntry->name[namelen] = 0;