iostream: check that stream is open before trying to read (tornadoweb…

…#2670)
ploxiln · Jul 4, 2019 · 8673547 · 8673547
1 parent a99f147
commit 8673547
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/tornado/iostream.py b/tornado/iostream.py
@@ -856,6 +856,7 @@ def _handle_read(self):
             self._maybe_run_close_callback()
 
     def _set_read_callback(self, callback):
+        self._check_closed()  # Before reading, check that stream is not closed.
         assert self._read_callback is None, "Already reading"
         assert self._read_future is None, "Already reading"
         if callback is not None: