diff options
Diffstat (limited to 'Lib/multiprocessing')
| -rw-r--r-- | Lib/multiprocessing/popen_spawn_win32.py | 15 | ||||
| -rw-r--r-- | Lib/multiprocessing/reduction.py | 10 | ||||
| -rw-r--r-- | Lib/multiprocessing/spawn.py | 10 |
3 files changed, 29 insertions, 6 deletions
diff --git a/Lib/multiprocessing/popen_spawn_win32.py b/Lib/multiprocessing/popen_spawn_win32.py index 3e42e9c..3b92c8a 100644 --- a/Lib/multiprocessing/popen_spawn_win32.py +++ b/Lib/multiprocessing/popen_spawn_win32.py @@ -18,6 +18,12 @@ TERMINATE = 0x10000 WINEXE = (sys.platform == 'win32' and getattr(sys, 'frozen', False)) WINSERVICE = sys.executable.lower().endswith("pythonservice.exe") + +def _close_handles(*handles): + for handle in handles: + _winapi.CloseHandle(handle) + + # # We define a Popen class similar to the one from subprocess, but # whose constructor takes a process object as its argument. @@ -32,8 +38,12 @@ class Popen(object): def __init__(self, process_obj): prep_data = spawn.get_preparation_data(process_obj._name) - # read end of pipe will be "stolen" by the child process + # read end of pipe will be duplicated by the child process # -- see spawn_main() in spawn.py. + # + # bpo-33929: Previously, the read end of pipe was "stolen" by the child + # process, but it leaked a handle if the child process had been + # terminated before it could steal the handle from the parent process. rhandle, whandle = _winapi.CreatePipe(None, 0) wfd = msvcrt.open_osfhandle(whandle, 0) cmd = spawn.get_command_line(parent_pid=os.getpid(), @@ -56,7 +66,8 @@ class Popen(object): self.returncode = None self._handle = hp self.sentinel = int(hp) - self.finalizer = util.Finalize(self, _winapi.CloseHandle, (self.sentinel,)) + self.finalizer = util.Finalize(self, _close_handles, + (self.sentinel, int(rhandle))) # send information to child set_spawning_popen(self) diff --git a/Lib/multiprocessing/reduction.py b/Lib/multiprocessing/reduction.py index deca19c..473fd59 100644 --- a/Lib/multiprocessing/reduction.py +++ b/Lib/multiprocessing/reduction.py @@ -68,12 +68,16 @@ if sys.platform == 'win32': __all__ += ['DupHandle', 'duplicate', 'steal_handle'] import _winapi - def duplicate(handle, target_process=None, inheritable=False): + def duplicate(handle, target_process=None, inheritable=False, + *, source_process=None): '''Duplicate a handle. (target_process is a handle not a pid!)''' + current_process = _winapi.GetCurrentProcess() + if source_process is None: + source_process = current_process if target_process is None: - target_process = _winapi.GetCurrentProcess() + target_process = current_process return _winapi.DuplicateHandle( - _winapi.GetCurrentProcess(), handle, target_process, + source_process, handle, target_process, 0, inheritable, _winapi.DUPLICATE_SAME_ACCESS) def steal_handle(source_pid, handle): diff --git a/Lib/multiprocessing/spawn.py b/Lib/multiprocessing/spawn.py index 1f4f3f4..2de4cb7 100644 --- a/Lib/multiprocessing/spawn.py +++ b/Lib/multiprocessing/spawn.py @@ -96,7 +96,15 @@ def spawn_main(pipe_handle, parent_pid=None, tracker_fd=None): assert is_forking(sys.argv), "Not forking" if sys.platform == 'win32': import msvcrt - new_handle = reduction.steal_handle(parent_pid, pipe_handle) + import _winapi + + if parent_pid is not None: + source_process = _winapi.OpenProcess( + _winapi.PROCESS_DUP_HANDLE, False, parent_pid) + else: + source_process = None + new_handle = reduction.duplicate(pipe_handle, + source_process=source_process) fd = msvcrt.open_osfhandle(new_handle, os.O_RDONLY) else: from . import semaphore_tracker |