GH-98539: fix ref cycle in _SSLProtocolTransport after close (#98540)

kumaraditya303 · web-flow · commit 62bf5d8d0a36 · 2022-10-22T09:11:27.000-07:00
diff --git a/Lib/asyncio/sslproto.py b/Lib/asyncio/sslproto.py
@@ -107,8 +107,11 @@ def close(self):
         protocol's connection_lost() method will (eventually) called
         with None as its argument.
         """
-        self._closed = True
-        self._ssl_protocol._start_shutdown()
+        if not self._closed:
+            self._closed = True
+            self._ssl_protocol._start_shutdown()
+        else:
+            self._ssl_protocol = None
 
     def __del__(self, _warnings=warnings):
         if not self._closed:
