From 8cb03d24071322908ab06ca0e906791bbcd5cefd Mon Sep 17 00:00:00 2001
From: "suren.gabrielyan" <suren.gabrielyan@espressif.com>
Date: Fri, 12 Feb 2021 13:18:59 +0400
Subject: [PATCH] mdns: add bound check when setting interface as duplicate

Closes IDF-2787

Partially addresses https://github.com/espressif/esp-idf/issues/6440


* Original commit: espressif/esp-idf@2b9d2c06f54924b680c41ae641978c8d81612f65
---
 components/mdns/mdns.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/components/mdns/mdns.c b/components/mdns/mdns.c
index 8bb30eed283..35cbe2293ee 100644
--- a/components/mdns/mdns.c
+++ b/components/mdns/mdns.c
@@ -2202,6 +2202,9 @@ static void _mdns_dup_interface(mdns_if_t tcpip_if)
 {
     uint8_t i;
     mdns_if_t other_if = _mdns_get_other_if (tcpip_if);
+    if (other_if == MDNS_IF_MAX) {
+        return; // no other interface found
+    }
     for (i=0; i<MDNS_IP_PROTOCOL_MAX; i++) {
         if (_mdns_server->interfaces[other_if].pcbs[i].pcb) {
             //stop this interface and mark as dup