From 592bacb6fc0833336c0453e818e9b95016e9fd47 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Wed, 23 Aug 2023 23:57:11 +0200 Subject: [PATCH] gh-108342: Make ssl TestPreHandshakeClose more reliable (#108370) * In preauth tests of test_ssl, explicitly break reference cycles invoving SingleConnectionTestServerThread to make sure that the thread is deleted. Otherwise, the test marks the environment as altered because the threading module sees a "dangling thread" (SingleConnectionTestServerThread). This test leak was introduced by the test added for the fix of issue gh-108310. * Use support.SHORT_TIMEOUT instead of hardcoded 1.0 or 2.0 seconds timeout. * SingleConnectionTestServerThread.run() catchs TimeoutError * Fix a race condition (missing synchronization) in test_preauth_data_to_tls_client(): the server now waits until the client connect() completed in call_after_accept(). * test_https_client_non_tls_response_ignored() calls server.join() explicitly. * Replace "localhost" with server.listener.getsockname()[0]. --- Lib/test/test_ssl.py | 102 ++++++++++++++++++++++++++++++------------- 1 file changed, 71 insertions(+), 31 deletions(-) diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py index ad5377ec059c0b..4e49dc5640d3f5 100644 --- a/Lib/test/test_ssl.py +++ b/Lib/test/test_ssl.py @@ -4672,12 +4672,16 @@ class TestPreHandshakeClose(unittest.TestCase): class SingleConnectionTestServerThread(threading.Thread): - def __init__(self, *, name, call_after_accept): + def __init__(self, *, name, call_after_accept, timeout=None): self.call_after_accept = call_after_accept self.received_data = b'' # set by .run() self.wrap_error = None # set by .run() self.listener = None # set by .start() self.port = None # set by .start() + if timeout is None: + self.timeout = support.SHORT_TIMEOUT + else: + self.timeout = timeout super().__init__(name=name) def __enter__(self): @@ -4700,13 +4704,19 @@ def start(self): self.ssl_ctx.load_cert_chain(certfile=ONLYCERT, keyfile=ONLYKEY) self.listener = socket.socket() self.port = socket_helper.bind_port(self.listener) - self.listener.settimeout(2.0) + self.listener.settimeout(self.timeout) self.listener.listen(1) super().start() def run(self): - conn, address = self.listener.accept() - self.listener.close() + try: + conn, address = self.listener.accept() + except TimeoutError: + # on timeout, just close the listener + return + finally: + self.listener.close() + with conn: if self.call_after_accept(conn): return @@ -4734,8 +4744,13 @@ def non_linux_skip_if_other_okay_error(self, err): # we're specifically trying to test. The way this test is written # is known to work on Linux. We'll skip it anywhere else that it # does not present as doing so. - self.skipTest(f"Could not recreate conditions on {sys.platform}:" - f" {err=}") + try: + self.skipTest(f"Could not recreate conditions on {sys.platform}:" + f" {err=}") + finally: + # gh-108342: Explicitly break the reference cycle + err = None + # If maintaining this conditional winds up being a problem. # just turn this into an unconditional skip anything but Linux. # The important thing is that our CI has the logic covered. @@ -4746,7 +4761,7 @@ def test_preauth_data_to_tls_server(self): def call_after_accept(unused): server_accept_called.set() - if not ready_for_server_wrap_socket.wait(2.0): + if not ready_for_server_wrap_socket.wait(support.SHORT_TIMEOUT): raise RuntimeError("wrap_socket event never set, test may fail.") return False # Tell the server thread to continue. @@ -4767,20 +4782,31 @@ def call_after_accept(unused): ready_for_server_wrap_socket.set() server.join() + wrap_error = server.wrap_error - self.assertEqual(b"", server.received_data) - self.assertIsInstance(wrap_error, OSError) # All platforms. - self.non_linux_skip_if_other_okay_error(wrap_error) - self.assertIsInstance(wrap_error, ssl.SSLError) - self.assertIn("before TLS handshake with data", wrap_error.args[1]) - self.assertIn("before TLS handshake with data", wrap_error.reason) - self.assertNotEqual(0, wrap_error.args[0]) - self.assertIsNone(wrap_error.library, msg="attr must exist") + server.wrap_error = None + try: + self.assertEqual(b"", server.received_data) + self.assertIsInstance(wrap_error, OSError) # All platforms. + self.non_linux_skip_if_other_okay_error(wrap_error) + self.assertIsInstance(wrap_error, ssl.SSLError) + self.assertIn("before TLS handshake with data", wrap_error.args[1]) + self.assertIn("before TLS handshake with data", wrap_error.reason) + self.assertNotEqual(0, wrap_error.args[0]) + self.assertIsNone(wrap_error.library, msg="attr must exist") + finally: + # gh-108342: Explicitly break the reference cycle + wrap_error = None + server = None def test_preauth_data_to_tls_client(self): + server_can_continue_with_wrap_socket = threading.Event() client_can_continue_with_wrap_socket = threading.Event() def call_after_accept(conn_to_client): + if not server_can_continue_with_wrap_socket.wait(support.SHORT_TIMEOUT): + print("ERROR: test client took too long") + # This forces an immediate connection close via RST on .close(). set_socket_so_linger_on_with_zero_timeout(conn_to_client) conn_to_client.send( @@ -4800,8 +4826,10 @@ def call_after_accept(conn_to_client): with socket.socket() as client: client.connect(server.listener.getsockname()) - if not client_can_continue_with_wrap_socket.wait(2.0): - self.fail("test server took too long.") + server_can_continue_with_wrap_socket.set() + + if not client_can_continue_with_wrap_socket.wait(support.SHORT_TIMEOUT): + self.fail("test server took too long") ssl_ctx = ssl.create_default_context() try: tls_client = ssl_ctx.wrap_socket( @@ -4815,24 +4843,31 @@ def call_after_accept(conn_to_client): tls_client.close() server.join() - self.assertEqual(b"", received_data) - self.assertIsInstance(wrap_error, OSError) # All platforms. - self.non_linux_skip_if_other_okay_error(wrap_error) - self.assertIsInstance(wrap_error, ssl.SSLError) - self.assertIn("before TLS handshake with data", wrap_error.args[1]) - self.assertIn("before TLS handshake with data", wrap_error.reason) - self.assertNotEqual(0, wrap_error.args[0]) - self.assertIsNone(wrap_error.library, msg="attr must exist") + try: + self.assertEqual(b"", received_data) + self.assertIsInstance(wrap_error, OSError) # All platforms. + self.non_linux_skip_if_other_okay_error(wrap_error) + self.assertIsInstance(wrap_error, ssl.SSLError) + self.assertIn("before TLS handshake with data", wrap_error.args[1]) + self.assertIn("before TLS handshake with data", wrap_error.reason) + self.assertNotEqual(0, wrap_error.args[0]) + self.assertIsNone(wrap_error.library, msg="attr must exist") + finally: + # gh-108342: Explicitly break the reference cycle + wrap_error = None + server = None def test_https_client_non_tls_response_ignored(self): - server_responding = threading.Event() class SynchronizedHTTPSConnection(http.client.HTTPSConnection): def connect(self): + # Call clear text HTTP connect(), not the encrypted HTTPS (TLS) + # connect(): wrap_socket() is called manually below. http.client.HTTPConnection.connect(self) + # Wait for our fault injection server to have done its thing. - if not server_responding.wait(1.0) and support.verbose: + if not server_responding.wait(support.SHORT_TIMEOUT) and support.verbose: sys.stdout.write("server_responding event never set.") self.sock = self._context.wrap_socket( self.sock, server_hostname=self.host) @@ -4847,28 +4882,33 @@ def call_after_accept(conn_to_client): server_responding.set() return True # Tell the server to stop. + timeout = 2.0 server = self.SingleConnectionTestServerThread( call_after_accept=call_after_accept, - name="non_tls_http_RST_responder") + name="non_tls_http_RST_responder", + timeout=timeout) self.enterContext(server) # starts it & unittest.TestCase stops it. # Redundant; call_after_accept sets SO_LINGER on the accepted conn. set_socket_so_linger_on_with_zero_timeout(server.listener) connection = SynchronizedHTTPSConnection( - f"localhost", + server.listener.getsockname()[0], port=server.port, context=ssl.create_default_context(), - timeout=2.0, + timeout=timeout, ) + # There are lots of reasons this raises as desired, long before this # test was added. Sending the request requires a successful TLS wrapped # socket; that fails if the connection is broken. It may seem pointless # to test this. It serves as an illustration of something that we never # want to happen... properly not happening. - with self.assertRaises(OSError) as err_ctx: + with self.assertRaises(OSError): connection.request("HEAD", "/test", headers={"Host": "localhost"}) response = connection.getresponse() + server.join() + class TestEnumerations(unittest.TestCase):