diff options
| -rw-r--r-- | Lib/threading.py | 21 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2021-09-23-22-17-26.bpo-45274.gPpa4E.rst | 5 |
2 files changed, 22 insertions, 4 deletions
diff --git a/Lib/threading.py b/Lib/threading.py index c2b94a5..1c74a8d 100644 --- a/Lib/threading.py +++ b/Lib/threading.py @@ -1094,11 +1094,24 @@ class Thread: # If the lock is acquired, the C code is done, and self._stop() is # called. That sets ._is_stopped to True, and ._tstate_lock to None. lock = self._tstate_lock - if lock is None: # already determined that the C code is done + if lock is None: + # already determined that the C code is done assert self._is_stopped - elif lock.acquire(block, timeout): - lock.release() - self._stop() + return + + try: + if lock.acquire(block, timeout): + lock.release() + self._stop() + except: + if lock.locked(): + # bpo-45274: lock.acquire() acquired the lock, but the function + # was interrupted with an exception before reaching the + # lock.release(). It can happen if a signal handler raises an + # exception, like CTRL+C which raises KeyboardInterrupt. + lock.release() + self._stop() + raise @property def name(self): diff --git a/Misc/NEWS.d/next/Library/2021-09-23-22-17-26.bpo-45274.gPpa4E.rst b/Misc/NEWS.d/next/Library/2021-09-23-22-17-26.bpo-45274.gPpa4E.rst new file mode 100644 index 0000000..94d06ce --- /dev/null +++ b/Misc/NEWS.d/next/Library/2021-09-23-22-17-26.bpo-45274.gPpa4E.rst @@ -0,0 +1,5 @@ +Fix a race condition in the :meth:`Thread.join() <threading.Thread.join>` +method of the :mod:`threading` module. If the function is interrupted by a +signal and the signal handler raises an exception, make sure that the thread +remains in a consistent state to prevent a deadlock. Patch by Victor +Stinner. |