network: ensure multicast bit is unset in random mac addresses

controller/src/ctl/mod.rs

@@ -85,6 +85,7 @@ impl Controller {
 
         let mut mac = MacAddr6::random();
         mac.set_local(true);
+        mac.set_multicast(false);
         let ipv4 = self.allocate_ipv4()?;
         let ipv6 = mac.to_link_local_ipv6();
         let launch_config = LaunchInfo {

network/src/backend.rs

@@ -132,6 +132,7 @@ impl NetworkBackend {
         let mac = self.force_mac_address.unwrap_or_else(|| {
             let mut mac = MacAddr6::random();
             mac.set_local(true);
+            mac.set_multicast(false);
             mac
         });
         let mac = smoltcp::wire::EthernetAddress(mac.to_array());