net: socket._getpeername

Fixes: nodejs#43009

If calling `this._handle.getpeername` returns an error at the first
call, its result shouldn't be cached to `this._peername`.

Signed-off-by: Daeyeon Jeong daeyeon.dev@gmail.com

lib/net.js

@@ -736,9 +736,11 @@ Socket.prototype._getpeername = function() {
   if (!this._handle || !this._handle.getpeername) {
     return this._peername || {};
   } else if (!this._peername) {
-    this._peername = {};
+    const out = {};
+    const err = this._handle.getpeername(out);
     // FIXME(bnoordhuis) Throw when the return value is not 0?
-    this._handle.getpeername(this._peername);
+    if (err) return {};
+    this._peername = out;
   }
   return this._peername;
 };