https://github.com/python/cpython/commit/7e9400c3e6e1322904204e7411494e8bc7b44237 commit: 7e9400c3e6e1322904204e7411494e8bc7b44237 branch: 3.14 author: Miss Islington (bot) <[email protected]> committer: kumaraditya303 <[email protected]> date: 2025-11-13T17:03:04+05:30 summary:
[3.14] gh-103847: fix cancellation safety of `asyncio.create_subprocess_exec` (GH-140805) (#141446) gh-103847: fix cancellation safety of `asyncio.create_subprocess_exec` (GH-140805) (cherry picked from commit ef474cfafbdf3aa383fb1334a7ab95cef9834ced) Co-authored-by: Kumar Aditya <[email protected]> files: A Misc/NEWS.d/next/Library/2025-10-31-13-57-55.gh-issue-103847.VM7TnW.rst M Lib/asyncio/base_subprocess.py M Lib/test/test_asyncio/test_subprocess.py diff --git a/Lib/asyncio/base_subprocess.py b/Lib/asyncio/base_subprocess.py index d40af422e614c1..321a4e5d5d18fb 100644 --- a/Lib/asyncio/base_subprocess.py +++ b/Lib/asyncio/base_subprocess.py @@ -26,6 +26,7 @@ def __init__(self, loop, protocol, args, shell, self._pending_calls = collections.deque() self._pipes = {} self._finished = False + self._pipes_connected = False if stdin == subprocess.PIPE: self._pipes[0] = None @@ -213,6 +214,7 @@ async def _connect_pipes(self, waiter): else: if waiter is not None and not waiter.cancelled(): waiter.set_result(None) + self._pipes_connected = True def _call(self, cb, *data): if self._pending_calls is not None: @@ -256,6 +258,15 @@ def _try_finish(self): assert not self._finished if self._returncode is None: return + if not self._pipes_connected: + # self._pipes_connected can be False if not all pipes were connected + # because either the process failed to start or the self._connect_pipes task + # got cancelled. In this broken state we consider all pipes disconnected and + # to avoid hanging forever in self._wait as otherwise _exit_waiters + # would never be woken up, we wake them up here. + for waiter in self._exit_waiters: + if not waiter.cancelled(): + waiter.set_result(self._returncode) if all(p is not None and p.disconnected for p in self._pipes.values()): self._finished = True diff --git a/Lib/test/test_asyncio/test_subprocess.py b/Lib/test/test_asyncio/test_subprocess.py index 3a17c169c34f12..bf301740741ae7 100644 --- a/Lib/test/test_asyncio/test_subprocess.py +++ b/Lib/test/test_asyncio/test_subprocess.py @@ -11,7 +11,7 @@ from asyncio import subprocess from test.test_asyncio import utils as test_utils from test import support -from test.support import os_helper +from test.support import os_helper, warnings_helper, gc_collect if not support.has_subprocess_support: raise unittest.SkipTest("test module requires subprocess") @@ -879,6 +879,44 @@ async def main(): self.loop.run_until_complete(main()) + @warnings_helper.ignore_warnings(category=ResourceWarning) + def test_subprocess_read_pipe_cancelled(self): + async def main(): + loop = asyncio.get_running_loop() + loop.connect_read_pipe = mock.AsyncMock(side_effect=asyncio.CancelledError) + with self.assertRaises(asyncio.CancelledError): + await asyncio.create_subprocess_exec(*PROGRAM_BLOCKED, stderr=asyncio.subprocess.PIPE) + + asyncio.run(main()) + gc_collect() + + @warnings_helper.ignore_warnings(category=ResourceWarning) + def test_subprocess_write_pipe_cancelled(self): + async def main(): + loop = asyncio.get_running_loop() + loop.connect_write_pipe = mock.AsyncMock(side_effect=asyncio.CancelledError) + with self.assertRaises(asyncio.CancelledError): + await asyncio.create_subprocess_exec(*PROGRAM_BLOCKED, stdin=asyncio.subprocess.PIPE) + + asyncio.run(main()) + gc_collect() + + @warnings_helper.ignore_warnings(category=ResourceWarning) + def test_subprocess_read_write_pipe_cancelled(self): + async def main(): + loop = asyncio.get_running_loop() + loop.connect_read_pipe = mock.AsyncMock(side_effect=asyncio.CancelledError) + loop.connect_write_pipe = mock.AsyncMock(side_effect=asyncio.CancelledError) + with self.assertRaises(asyncio.CancelledError): + await asyncio.create_subprocess_exec( + *PROGRAM_BLOCKED, + stdin=asyncio.subprocess.PIPE, + stdout=asyncio.subprocess.PIPE, + stderr=asyncio.subprocess.PIPE, + ) + + asyncio.run(main()) + gc_collect() if sys.platform != 'win32': # Unix diff --git a/Misc/NEWS.d/next/Library/2025-10-31-13-57-55.gh-issue-103847.VM7TnW.rst b/Misc/NEWS.d/next/Library/2025-10-31-13-57-55.gh-issue-103847.VM7TnW.rst new file mode 100644 index 00000000000000..e14af7d97083d6 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2025-10-31-13-57-55.gh-issue-103847.VM7TnW.rst @@ -0,0 +1 @@ +Fix hang when cancelling process created by :func:`asyncio.create_subprocess_exec` or :func:`asyncio.create_subprocess_shell`. Patch by Kumar Aditya. _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
