From 35424b375a5346719013ca14a23e1ee9d6efc6a9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Przemys=C5=82aw=20Bida?= <przemyslaw.bida@nordicsemi.no>
Date: Wed, 13 Dec 2023 03:28:26 +0100
Subject: [PATCH] [posix] verify in `otPlatUdpBindToNetif` if Backbone
 Interface is set. (#9696)

Commit adds check to `otPlatUdpBindToNetif` if backbone interface is
set to correct value to prevent `setsockopt` from crashing the
ot-daemon.
---
 src/posix/platform/udp.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/posix/platform/udp.cpp b/src/posix/platform/udp.cpp
index 6d7c880a3..5726f0ede 100644
--- a/src/posix/platform/udp.cpp
+++ b/src/posix/platform/udp.cpp
@@ -323,6 +323,11 @@ otError otPlatUdpBindToNetif(otUdpSocket *aUdpSocket, otNetifIdentifier aNetifId
     case OT_NETIF_BACKBONE:
     {
 #if OPENTHREAD_CONFIG_BACKBONE_ROUTER_ENABLE
+        if (otSysGetInfraNetifName() == nullptr || otSysGetInfraNetifName()[0] == '\0')
+        {
+            otLogWarnPlat("No backbone interface given, %s fails.", __func__);
+            ExitNow(error = OT_ERROR_INVALID_ARGS);
+        }
 #if __linux__
         VerifyOrExit(setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, otSysGetInfraNetifName(),
                                 strlen(otSysGetInfraNetifName())) == 0,