Added os.setns and os.unshare to easily switch between namespaces
on Linux.
Co-authored-by: Christian Heimes <christian@python.org>
Co-authored-by: CAM Gerlach <CAM.Gerlach@Gerlach.CAM>
Co-authored-by: Victor Stinner <vstinner@python.org>
Integer to and from text conversions via CPython's bignum `int` type is not safe against denial of service attacks due to malicious input. Very large input strings with hundred thousands of digits can consume several CPU seconds.
This PR comes fresh from a pile of work done in our private PSRT security response team repo.
Signed-off-by: Christian Heimes [Red Hat] <christian@python.org>
Tons-of-polishing-up-by: Gregory P. Smith [Google] <greg@krypto.org>
Reviews via the private PSRT repo via many others (see the NEWS entry in the PR).
<!-- gh-issue-number: gh-95778 -->
* Issue: gh-95778
<!-- /gh-issue-number -->
I wrote up [a one pager for the release managers](https://docs.google.com/document/d/1KjuF_aXlzPUxTK4BMgezGJ2Pn7uevfX7g0_mvgHlL7Y/edit#). Much of that text wound up in the Issue. Backports PRs already exist. See the issue for links.
We only statically initialize for core code and builtin modules. Extension modules still create
the tuple at runtime. We'll solve that part of interpreter isolation separately.
This change includes generated code. The non-generated changes are in:
* Tools/clinic/clinic.py
* Python/getargs.c
* Include/cpython/modsupport.h
* Makefile.pre.in (re-generate global strings after running clinic)
* very minor tweaks to Modules/_codecsmodule.c and Python/Python-tokenize.c
All other changes are generated code (clinic, global strings).
It combines PyImport_ImportModule() and PyObject_GetAttrString()
and saves 4-6 lines of code on every use.
Add also _PyImport_GetModuleAttr() which takes Python strings as arguments.
In a gh-32003 comment, I realized it wasn't very clear how _Py_DECLARE_STR() should be used. This changes adds a comment to clarify.
https://bugs.python.org/issue46541
Add methods __typing_subst__() in TypeVar and ParamSpec.
Simplify code by using more object-oriented approach, especially
the C code for types.GenericAlias and the Python code for
collections.abc.Callable.
Instead of manually enumerating the global strings in generate_global_objects.py, we extrapolate the list from usage of _Py_ID() and _Py_STR() in the source files.
This is partly inspired by gh-31261.
https://bugs.python.org/issue46541
We're no longer using _Py_IDENTIFIER() (or _Py_static_string()) in any core CPython code. It is still used in a number of non-builtin stdlib modules.
The replacement is: PyUnicodeObject (not pointer) fields under _PyRuntimeState, statically initialized as part of _PyRuntime. A new _Py_GET_GLOBAL_IDENTIFIER() macro facilitates lookup of the fields (along with _Py_GET_GLOBAL_STRING() for non-identifier strings).
https://bugs.python.org/issue46541#msg411799 explains the rationale for this change.
The core of the change is in:
* (new) Include/internal/pycore_global_strings.h - the declarations for the global strings, along with the macros
* Include/internal/pycore_runtime_init.h - added the static initializers for the global strings
* Include/internal/pycore_global_objects.h - where the struct in pycore_global_strings.h is hooked into _PyRuntimeState
* Tools/scripts/generate_global_objects.py - added generation of the global string declarations and static initializers
I've also added a --check flag to generate_global_objects.py (along with make check-global-objects) to check for unused global strings. That check is added to the PR CI config.
The remainder of this change updates the core code to use _Py_GET_GLOBAL_IDENTIFIER() instead of _Py_IDENTIFIER() and the related _Py*Id functions (likewise for _Py_GET_GLOBAL_STRING() instead of _Py_static_string()). This includes adding a few functions where there wasn't already an alternative to _Py*Id(), replacing the _Py_Identifier * parameter with PyObject *.
The following are not changed (yet):
* stop using _Py_IDENTIFIER() in the stdlib modules
* (maybe) get rid of _Py_IDENTIFIER(), etc. entirely -- this may not be doable as at least one package on PyPI using this (private) API
* (maybe) intern the strings during runtime init
https://bugs.python.org/issue46541
Pablo Galindo Salgado
Kaushik Kulkarni
Kumar Aditya
Noam Cohen
Victor Stinner
Nikita Sobolev
Steve Dower
Gregory P. Smith
Irit Katriel
Eric Snow
Serhiy Storchaka
Dennis Sweeney
Inada Naoki
penguin_wwy
Brandt Bucher