diff --git a/config.h b/config.h
index 8bcdbc3..306fd48 100644
--- a/config.h
+++ b/config.h
@@ -25,10 +25,11 @@
 #include "transport.h"
 
 #define MAX_PORTS 8
+#define MAX_IFNAME_SIZE 16
 
 /** Defines a network interface, with PTP options. */
 struct interface {
-	char *name;
+	char name[MAX_IFNAME_SIZE + 1];
 	enum delay_mechanism dm;
 	enum transport_type transport;
 };
diff --git a/ptp4l.c b/ptp4l.c
index 899cc42..8c47ee1 100644
--- a/ptp4l.c
+++ b/ptp4l.c
@@ -152,7 +152,7 @@ int main(int argc, char *argv[])
 			break;
 		case 'i':
 			if (*nports < MAX_PORTS) {
-				iface[*nports].name = optarg;
+				strncpy(iface[*nports].name, optarg, MAX_IFNAME_SIZE);
 				iface[*nports].dm = *dm;
 				iface[*nports].transport = *transport;
 				(*nports)++;