Fix crash at startup when Device is not specified on OS X.

diff --git a/src/bsd/device.c b/src/bsd/device.c
index 303e9b6..0d41c96 100644 (file)
--- a/src/bsd/device.c
+++ b/src/bsd/device.c
@@ -147,7 +147,7 @@ static bool setup_device(void) {
                }
        } else {
 #ifdef HAVE_NET_IF_UTUN_H
-               if(strncmp(device, "utun", 4) == 0 || strncmp(device, "/dev/utun", 9) == 0)
+               if(device && (strncmp(device, "utun", 4) == 0 || strncmp(device, "/dev/utun", 9) == 0))
                        device_type = DEVICE_TYPE_UTUN;
                else
 #endif