diff --git a/src/sys/socket/mod.rs b/src/sys/socket/mod.rs
index e9537c4b0c..4ee1aceec7 100644
--- a/src/sys/socket/mod.rs
+++ b/src/sys/socket/mod.rs
@@ -678,7 +678,7 @@ pub fn sendmsg<'a>(fd: RawFd, iov: &[IoVec<&'a [u8]>], cmsgs: &[ControlMessage<'
     {
         let mut ofs = 0;
         for cmsg in cmsgs {
-            let mut ptr = &mut cmsg_buffer[ofs..];
+            let ptr = &mut cmsg_buffer[ofs..];
             unsafe {
                 cmsg.encode_into(ptr);
             }