fix bug where a null node is removed from the linked list

lib/io.js

@@ -169,8 +169,8 @@ class IO {
     if (message.command === '_holepunch') this._holepunch(req)
   }
 
-  _cancel (rid, err) {
-    this._finish(rid, err || ECANCELLED, null, null)
+  _cancel (rid, err, peer) {
+    this._finish(rid, err || ECANCELLED, null, peer)
   }
 
   _onrotate () {
@@ -193,7 +193,7 @@ class IO {
         continue
       }
 
-      this._cancel(req.rid, ETIMEDOUT)
+      this._cancel(req.rid, ETIMEDOUT, req.peer)
       i-- // the cancel removes the entry so we need to dec i
     }
 
@@ -213,8 +213,8 @@ class IO {
     const pending = this._pending
     this._pending = []
 
-    for (const req of pending) req.callback(ECANCELLED)
-    for (const req of this.inflight) this._cancel(req.rid)
+    for (const req of pending) req.callback(ECANCELLED, null, req.peer)
+    for (const req of this.inflight) this._cancel(req.rid, null, req.peer)
   }
 
   response (request, value, closerNodes, peer) {