From 260f2dde5726b00cbb02e2503eca32f99bf5292b Mon Sep 17 00:00:00 2001
From: "Tokita, Hiroshi" <tokita.hiroshi@gmail.com>
Date: Wed, 2 Jun 2021 05:04:48 +0900
Subject: [PATCH] [posix] fix strncpy warning about null terminated string
 length (#6698)

---
 src/posix/platform/backbone.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/posix/platform/backbone.cpp b/src/posix/platform/backbone.cpp
index 83d9aedc8..f96fbec5e 100644
--- a/src/posix/platform/backbone.cpp
+++ b/src/posix/platform/backbone.cpp
@@ -52,8 +52,9 @@ void platformBackboneInit(otInstance *aInstance, const char *aInterfaceName)
 
     VerifyOrExit(aInterfaceName != nullptr && aInterfaceName[0] != '\0');
 
-    VerifyOrDie(strnlen(aInterfaceName, IFNAMSIZ) <= IFNAMSIZ - 1, OT_EXIT_INVALID_ARGUMENTS);
-    strncpy(gBackboneNetifName, aInterfaceName, sizeof(gBackboneNetifName));
+    VerifyOrDie(strnlen(aInterfaceName, sizeof(gBackboneNetifName)) < sizeof(gBackboneNetifName),
+                OT_EXIT_INVALID_ARGUMENTS);
+    strcpy(gBackboneNetifName, aInterfaceName);
 
     gBackboneNetifIndex = if_nametoindex(gBackboneNetifName);
     VerifyOrDie(gBackboneNetifIndex > 0, OT_EXIT_FAILURE);