diff --git a/src/openvpn/networking_sitnl.c b/src/openvpn/networking_sitnl.c
index 4e29d8ba..ea730ec7 100644
--- a/src/openvpn/networking_sitnl.c
+++ b/src/openvpn/networking_sitnl.c
@@ -494,7 +494,7 @@ sitnl_route_best_gw(sa_family_t af_family, const inet_address_t *dst,
 
     /* save result in output variables */
     memcpy(best_gw, &res.gw, res.addr_size);
-    strcpy(best_iface, res.iface);
+    strncpy(best_iface, res.iface, IFNAMSIZ);
 err:
     return ret;
 
diff --git a/src/openvpn/route.h b/src/openvpn/route.h
index 31d38e36..2e68091c 100644
--- a/src/openvpn/route.h
+++ b/src/openvpn/route.h
@@ -184,7 +184,11 @@ struct route_ipv6_gateway_info {
 #ifdef _WIN32
     DWORD adapter_index; /* interface or ~0 if undefined */
 #else
-    char iface[16]; /* interface name (null terminated), may be empty */
+    /* non linux platform don't have this constant defined */
+#ifndef IFNAMSIZ
+#define IFNAMSIZ 16
+#endif
+    char iface[IFNAMSIZ]; /* interface name (null terminated), may be empty */
 #endif
 
     /* gateway interface hardware address */