From 0ba07b2108d4763273f3fb85544dde34c5acd40a Mon Sep 17 00:00:00 2001 From: Eric Snow Date: Fri, 21 Jul 2023 08:34:09 -0600 Subject: [PATCH] gh-105699: Fix a Crasher Related to a Deprecated Global Variable (gh-106923) There was a slight race in _Py_ClearFileSystemEncoding() (when called from _Py_SetFileSystemEncoding()), between freeing the value and setting the variable to NULL, which occasionally caused crashes when multiple isolated interpreters were used. (Notably, I saw at least 10 different, seemingly unrelated spooky-action-at-a-distance, ways this crashed. Yay, free threading!) We avoid the problem by only setting the global variables with the main interpreter (i.e. runtime init). --- .../2023-07-20-12-21-37.gh-issue-105699.08ywGV.rst | 4 ++++ Objects/unicodeobject.c | 11 +++++++---- 2 files changed, 11 insertions(+), 4 deletions(-) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2023-07-20-12-21-37.gh-issue-105699.08ywGV.rst diff --git a/Misc/NEWS.d/next/Core and Builtins/2023-07-20-12-21-37.gh-issue-105699.08ywGV.rst b/Misc/NEWS.d/next/Core and Builtins/2023-07-20-12-21-37.gh-issue-105699.08ywGV.rst new file mode 100644 index 00000000000..82312718cd0 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2023-07-20-12-21-37.gh-issue-105699.08ywGV.rst @@ -0,0 +1,4 @@ +Python no longer crashes due to an infrequent race in setting +``Py_FileSystemDefaultEncoding`` and ``Py_FileSystemDefaultEncodeErrors`` +(both deprecated), when simultaneously initializing two isolated +subinterpreters. Now they are only set during runtime initialization. diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index e8e8cab99c8..fe2660c6ce6 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -15189,10 +15189,13 @@ init_fs_codec(PyInterpreterState *interp) /* Set Py_FileSystemDefaultEncoding and Py_FileSystemDefaultEncodeErrors global configuration variables. */ - if (_Py_SetFileSystemEncoding(fs_codec->encoding, - fs_codec->errors) < 0) { - PyErr_NoMemory(); - return -1; + if (_Py_IsMainInterpreter(interp)) { + + if (_Py_SetFileSystemEncoding(fs_codec->encoding, + fs_codec->errors) < 0) { + PyErr_NoMemory(); + return -1; + } } return 0; }