From 98d90f745d35d5d07bffcb46788b50e05eea56c6 Mon Sep 17 00:00:00 2001 From: Christian Heimes Date: Tue, 27 Aug 2019 23:36:56 +0200 Subject: bpo-37951: Lift subprocess's fork() restriction (GH-15544) --- Doc/library/subprocess.rst | 7 +++++++ Doc/whatsnew/3.8.rst | 6 ++++++ Misc/NEWS.d/next/Library/2019-08-27-10-03-48.bpo-37951.MfRQgL.rst | 2 ++ Modules/_posixsubprocess.c | 6 ++++-- 4 files changed, 19 insertions(+), 2 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2019-08-27-10-03-48.bpo-37951.MfRQgL.rst diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst index 7e1e3f9..167ed9a 100644 --- a/Doc/library/subprocess.rst +++ b/Doc/library/subprocess.rst @@ -483,6 +483,13 @@ functions. The *start_new_session* parameter can take the place of a previously common use of *preexec_fn* to call os.setsid() in the child. + .. versionchanged:: 3.8 + + The *preexec_fn* parameter is no longer supported in subinterpreters. + The use of the parameter in a subinterpreter raises + :exc:`RuntimeError`. The new restriction may affect applications that + are deployed in mod_wsgi, uWSGI, and other embedded environments. + If *close_fds* is true, all file descriptors except :const:`0`, :const:`1` and :const:`2` will be closed before the child process is executed. Otherwise when *close_fds* is false, file descriptors obey their inheritable flag diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst index cd31cf6..bcdb60d 100644 --- a/Doc/whatsnew/3.8.rst +++ b/Doc/whatsnew/3.8.rst @@ -1531,6 +1531,12 @@ Changes in the Python API non-zero :attr:`~Popen.returncode`. (Contributed by Joannah Nanjekye and Victor Stinner in :issue:`35537`.) +* The *preexec_fn* argument of * :class:`subprocess.Popen` is no longer + compatible with subinterpreters. The use of the parameter in a + subinterpreter now raises :exc:`RuntimeError`. + (Contributed by Eric Snow in :issue:`34651`, modified by Christian Heimes + in :issue:`37951`.) + * The :meth:`imap.IMAP4.logout` method no longer ignores silently arbitrary exceptions. diff --git a/Misc/NEWS.d/next/Library/2019-08-27-10-03-48.bpo-37951.MfRQgL.rst b/Misc/NEWS.d/next/Library/2019-08-27-10-03-48.bpo-37951.MfRQgL.rst new file mode 100644 index 0000000..18e4c62 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-08-27-10-03-48.bpo-37951.MfRQgL.rst @@ -0,0 +1,2 @@ +Most features of the subprocess module now work again in subinterpreters. +Only *preexec_fn* is restricted in subinterpreters. diff --git a/Modules/_posixsubprocess.c b/Modules/_posixsubprocess.c index 60c8eab..f68d362 100644 --- a/Modules/_posixsubprocess.c +++ b/Modules/_posixsubprocess.c @@ -583,8 +583,10 @@ subprocess_fork_exec(PyObject* self, PyObject *args) &restore_signals, &call_setsid, &preexec_fn)) return NULL; - if (_PyInterpreterState_Get() != PyInterpreterState_Main()) { - PyErr_SetString(PyExc_RuntimeError, "fork not supported for subinterpreters"); + if ((preexec_fn != Py_None) && + (_PyInterpreterState_Get() != PyInterpreterState_Main())) { + PyErr_SetString(PyExc_RuntimeError, + "preexec_fn not supported within subinterpreters"); return NULL; } -- cgit v0.12