From 38e32872eb3cf0dc9dd8cef9b05e47ba03638d34 Mon Sep 17 00:00:00 2001 From: "Miss Islington (bot)" <31488909+miss-islington@users.noreply.github.com> Date: Sun, 30 Aug 2020 12:42:27 -0700 Subject: bpo-41344: Raise ValueError when creating shared memory of size 0 (GH-21556) (GH-22019) (cherry picked from commit 475a5fbb5644ea200c990d85d8c264e78ab6c7ea) Co-authored-by: Vinay Sharma Co-authored-by: Vinay Sharma --- Lib/multiprocessing/shared_memory.py | 2 ++ Lib/test/_test_multiprocessing.py | 12 ++++++++++++ .../next/Library/2020-07-20-13-27-48.bpo-41344.iKipNd.rst | 1 + 3 files changed, 15 insertions(+) create mode 100644 Misc/NEWS.d/next/Library/2020-07-20-13-27-48.bpo-41344.iKipNd.rst diff --git a/Lib/multiprocessing/shared_memory.py b/Lib/multiprocessing/shared_memory.py index f92eb01..e5b5e6c 100644 --- a/Lib/multiprocessing/shared_memory.py +++ b/Lib/multiprocessing/shared_memory.py @@ -75,6 +75,8 @@ class SharedMemory: raise ValueError("'size' must be a positive integer") if create: self._flags = _O_CREX | os.O_RDWR + if size == 0: + raise ValueError("'size' must be a positive number different from zero") if name is None and not self._flags & os.O_EXCL: raise ValueError("'name' can only be None if create=True") diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py index 8626aa3..ee9b47b 100644 --- a/Lib/test/_test_multiprocessing.py +++ b/Lib/test/_test_multiprocessing.py @@ -3827,6 +3827,18 @@ class _TestSharedMemory(BaseTestCase): sms.close() + # Test creating a shared memory segment with negative size + with self.assertRaises(ValueError): + sms_invalid = shared_memory.SharedMemory(create=True, size=-1) + + # Test creating a shared memory segment with size 0 + with self.assertRaises(ValueError): + sms_invalid = shared_memory.SharedMemory(create=True, size=0) + + # Test creating a shared memory segment without size argument + with self.assertRaises(ValueError): + sms_invalid = shared_memory.SharedMemory(create=True) + def test_shared_memory_across_processes(self): # bpo-40135: don't define shared memory block's name in case of # the failure when we run multiprocessing tests in parallel. diff --git a/Misc/NEWS.d/next/Library/2020-07-20-13-27-48.bpo-41344.iKipNd.rst b/Misc/NEWS.d/next/Library/2020-07-20-13-27-48.bpo-41344.iKipNd.rst new file mode 100644 index 0000000..475bc9b --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-07-20-13-27-48.bpo-41344.iKipNd.rst @@ -0,0 +1 @@ +Prevent creating :class:`shared_memory.SharedMemory` objects with :code:`size=0`. -- cgit v0.12