From 8642dc4aa758538b96fa13f27d4fbd98863a0f7a Mon Sep 17 00:00:00 2001
From: Scott Shawcroft <scott@tannewt.org>
Date: Wed, 23 Mar 2022 17:17:48 -0700
Subject: [PATCH] Fix MDNS crash on S2

Fixes #6186
---
 ports/espressif/common-hal/mdns/Server.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/ports/espressif/common-hal/mdns/Server.c b/ports/espressif/common-hal/mdns/Server.c
index 2f260bbde0..9da67a9145 100644
--- a/ports/espressif/common-hal/mdns/Server.c
+++ b/ports/espressif/common-hal/mdns/Server.c
@@ -117,6 +117,11 @@ mp_obj_t common_hal_mdns_server_find(mdns_server_obj_t *self, const char *servic
         next = next->next;
     }
     mp_obj_tuple_t *tuple = MP_OBJ_TO_PTR(mp_obj_new_tuple(num_results, NULL));
+    // The empty tuple object is shared and stored in flash so return early if
+    // we got it. Without this we'll crash when trying to set len below.
+    if (num_results == 0) {
+        return MP_OBJ_FROM_PTR(tuple);
+    }
     next = results;
     // Don't error if we're out of memory. Instead, truncate the tuple.
     uint8_t added = 0;