diff --git a/net_util/src/mac.rs b/net_util/src/mac.rs
index 548829a48..ff01e49a9 100644
--- a/net_util/src/mac.rs
+++ b/net_util/src/mac.rs
@@ -57,7 +57,7 @@ impl MacAddr {
         // TODO: using something like std::mem::uninitialized could avoid the extra initialization,
         // if this ever becomes a performance bottleneck.
         let mut bytes = [0u8; MAC_ADDR_LEN];
-        bytes[..].copy_from_slice(&src[..]);
+        bytes[..].copy_from_slice(&src);
 
         MacAddr { bytes }
     }