--- a/dom/media/gmp/rlz/mac/lib/machine_id_mac.cc
+++ b/dom/media/gmp/rlz/mac/lib/machine_id_mac.cc
@@ -216,18 +216,19 @@ bool GetMACAddressFromIterator(io_iterat
                                uint8_t* buffer, size_t buffer_size) {
   if (buffer_size < kIOEthernetAddressSize)
     return false;
 
   bool success = false;
 
   bzero(buffer, buffer_size);
   base::mac::ScopedIOObject<io_object_t> primary_interface;
-  while (primary_interface.reset(IOIteratorNext(primary_interface_iterator)),
-         primary_interface) {
+  for (primary_interface.reset(IOIteratorNext(primary_interface_iterator));
+       primary_interface;
+       primary_interface.reset(IOIteratorNext(primary_interface_iterator))) {
     io_object_t primary_interface_parent;
     kern_return_t kern_result = IORegistryEntryGetParentEntry(
         primary_interface, kIOServicePlane, &primary_interface_parent);
     base::mac::ScopedIOObject<io_object_t> primary_interface_parent_deleter(
         primary_interface_parent);
     success = kern_result == KERN_SUCCESS;
 
     if (!success)