File CVE-2023-6597-TempDir-cleaning-symlink.patch of Package python3-doc

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File CVE-2023-6597-TempDir-cleaning-symlink.patch of Package python3-doc (Revision ecd125339bb037eb0819c24784fc3163)

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From d8f50e5e191027ad3358bafe6828a1263d3c0cda Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=B8ren=20L=C3=B8vborg?= <sorenl@unity3d.com>
Date: Thu, 1 Dec 2022 14:30:26 +0100
Subject: [PATCH 01/12] tempfile tests: try not to leave NOUNLINK files behind

During development, it becomes tiresome to have to manually clean up
these files in case of unrelated TemporaryDirectory breakage.
---
 Lib/posixpath.py                                                       |   36 ++
 Lib/tempfile.py                                                        |  148 ++++++++--
 Lib/test/support/__init__.py                                           |   31 ++
 Lib/test/test_tempfile.py                                              |   99 ++++++
 Misc/NEWS.d/next/Library/2022-12-01-16-57-44.gh-issue-91133.LKMVCV.rst |    2 
 5 files changed, 301 insertions(+), 15 deletions(-)

--- a/Lib/posixpath.py
+++ b/Lib/posixpath.py
@@ -455,3 +455,39 @@ def relpath(path, start=None):
     if not rel_list:
         return curdir
     return join(*rel_list)
+
+def commonpath(paths):
+    """Given a sequence of path names, returns the longest common sub-path."""
+
+    if not paths:
+        raise ValueError('commonpath() arg is an empty sequence')
+
+    if isinstance(paths[0], bytes):
+        sep = b'/'
+        curdir = b'.'
+    else:
+        sep = '/'
+        curdir = '.'
+
+    try:
+        split_paths = [path.split(sep) for path in paths]
+
+        try:
+            isabs, = set(p[:1] == sep for p in paths)
+        except ValueError:
+            raise ValueError("Can't mix absolute and relative paths") from None
+
+        split_paths = [[c for c in s if c and c != curdir] for s in split_paths]
+        s1 = min(split_paths)
+        s2 = max(split_paths)
+        common = s1
+        for i, c in enumerate(s1):
+            if c != s2[i]:
+                common = s1[:i]
+                break
+
+        prefix = sep if isabs else sep[:0]
+        return prefix + sep.join(common)
+    except (TypeError, AttributeError):
+        genericpath._check_arg_types('commonpath', *paths)
+        raise
--- a/Lib/tempfile.py
+++ b/Lib/tempfile.py
@@ -21,7 +21,7 @@ __all__ = [
     "mkstemp", "mkdtemp",                  # low level safe interfaces
     "mktemp",                              # deprecated unsafe interface
     "TMP_MAX", "gettempprefix",            # constants
-    "tempdir", "gettempdir"
+    "tempdir", "gettempdir", "gettempdirb"
    ]
 
 
@@ -82,6 +82,45 @@ def _exists(fn):
     else:
         return True
 
+
+def _infer_return_type(*args):
+    """Look at the type of all args and divine their implied return type."""
+    return_type = None
+    for arg in args:
+        if arg is None:
+            continue
+        if isinstance(arg, bytes):
+            if return_type is str:
+                raise TypeError("Can't mix bytes and non-bytes in "
+                                "path components.")
+            return_type = bytes
+        else:
+            if return_type is bytes:
+                raise TypeError("Can't mix bytes and non-bytes in "
+                                "path components.")
+            return_type = str
+    if return_type is None:
+        return str  # tempfile APIs return a str by default.
+    return return_type
+
+
+def _sanitize_params(prefix, suffix, dir):
+    """Common parameter processing for most APIs in this module."""
+    output_type = _infer_return_type(prefix, suffix, dir)
+    if suffix is None:
+        suffix = output_type()
+    if prefix is None:
+        if output_type is str:
+            prefix = template
+        else:
+            prefix = _os.fsencode(template)
+    if dir is None:
+        if output_type is str:
+            dir = gettempdir()
+        else:
+            dir = gettempdirb()
+    return prefix, suffix, dir, output_type
+
 class _RandomNameSequence:
     """An instance of _RandomNameSequence generates an endless
     sequence of unpredictable strings which can safely be incorporated
@@ -220,6 +259,22 @@ def _mkstemp_inner(dir, pre, suf, flags)
     raise FileExistsError(_errno.EEXIST,
                           "No usable temporary file name found")
 
+def _dont_follow_symlinks(func, path, *args):
+    # Pass follow_symlinks=False, unless not supported on this platform.
+    if func in _os.supports_follow_symlinks:
+        func(path, *args, follow_symlinks=False)
+    elif _os.name == 'nt' or not _os.path.islink(path):
+        func(path, *args)
+
+def _resetperms(path):
+    try:
+        chflags = _os.chflags
+    except AttributeError:
+        pass
+    else:
+        _dont_follow_symlinks(chflags, path, 0)
+    _dont_follow_symlinks(_os.chmod, path, 0o700)
+
 
 # User visible interfaces.
 
@@ -241,6 +296,12 @@ def gettempdir():
             _once_lock.release()
     return tempdir
 
+
+def gettempdirb():
+    """A bytes version of tempfile.gettempdir()."""
+    return _os.fsencode(gettempdir())
+
+
 def mkstemp(suffix="", prefix=template, dir=None, text=False):
     """User-callable function to create and return a unique temporary
     file.  The return value is a pair (fd, name) where fd is the
@@ -277,7 +338,6 @@ def mkstemp(suffix="", prefix=template,
 
     return _mkstemp_inner(dir, prefix, suffix, flags)
 
-
 def mkdtemp(suffix="", prefix=template, dir=None):
     """User-callable function to create and return a unique temporary
     directory.  The return value is the pathname of the directory.
@@ -291,17 +351,17 @@ def mkdtemp(suffix="", prefix=template,
     Caller is responsible for deleting the directory when done with it.
     """
 
-    if dir is None:
-        dir = gettempdir()
+    prefix, suffix, dir, output_type = _sanitize_params(prefix, suffix, dir)
 
     names = _get_candidate_names()
+    if output_type is bytes:
+        names = map(_os.fsencode, names)
 
     for seq in range(TMP_MAX):
         name = next(names)
         file = _os.path.join(dir, prefix + name + suffix)
         try:
             _os.mkdir(file, 0o700)
-            return file
         except FileExistsError:
             continue    # try again
         except PermissionError:
@@ -312,10 +372,12 @@ def mkdtemp(suffix="", prefix=template,
                 continue
             else:
                 raise
+        return file
 
     raise FileExistsError(_errno.EEXIST,
                           "No usable temporary directory name found")
 
+
 def mktemp(suffix="", prefix=template, dir=None):
     """User-callable function to return a unique temporary file name.  The
     file is not created.
@@ -675,7 +737,7 @@ class SpooledTemporaryFile:
         return rv
 
 
-class TemporaryDirectory(object):
+class TemporaryDirectory:
     """Create and return a temporary directory.  This has the same
     behavior as mkdtemp but can be used as a context manager.  For
     example:
@@ -684,20 +746,75 @@ class TemporaryDirectory(object):
             ...
 
     Upon exiting the context, the directory and everything contained
-    in it are removed.
+    in it are removed (unless delete=False is passed or an exception
+    is raised during cleanup and ignore_cleanup_errors is not True).
+
+    Optional Arguments:
+        suffix - A str suffix for the directory name.  (see mkdtemp)
+        prefix - A str prefix for the directory name.  (see mkdtemp)
+        dir - A directory to create this temp dir in.  (see mkdtemp)
+        ignore_cleanup_errors - False; ignore exceptions during cleanup?
+        delete - True; whether the directory is automatically deleted.
     """
 
-    def __init__(self, suffix="", prefix=template, dir=None):
+    def __init__(self, suffix=None, prefix=None, dir=None,
+                 ignore_cleanup_errors=False, *, delete=True):
         self.name = mkdtemp(suffix, prefix, dir)
+        self._ignore_cleanup_errors = ignore_cleanup_errors
+        self._delete = delete
         self._finalizer = _weakref.finalize(
             self, self._cleanup, self.name,
-            warn_message="Implicitly cleaning up {!r}".format(self))
+            warn_message="Implicitly cleaning up {!r}".format(self),
+            ignore_errors=self._ignore_cleanup_errors, delete=self._delete)
 
     @classmethod
-    def _cleanup(cls, name, warn_message):
-        _shutil.rmtree(name)
-        _warnings.warn(warn_message, ResourceWarning)
+    def _rmtree(cls, name, ignore_errors=False, repeated=False):
+        def onexc(func, path, exc_info):
+            exc = exc_info[1]
+            if isinstance(exc, PermissionError):
+                if repeated and path == name:
+                    if ignore_errors:
+                        return
+                    raise
+
+                try:
+                    if path != name:
+                        _resetperms(_os.path.dirname(path))
+                    _resetperms(path)
 
+                    try:
+                        _os.unlink(path)
+                    except IsADirectoryError:
+                        cls._rmtree(path)
+                    except PermissionError:
+                        # The PermissionError handler was originally added for
+                        # FreeBSD in directories, but it seems that it is raised
+                        # on Windows too.
+                        # bpo-43153: Calling _rmtree again may
+                        # raise NotADirectoryError and mask the PermissionError.
+                        # So we must re-raise the current PermissionError if
+                        # path is not a directory.
+                        if not _os.path.isdir(path) or _os.path.isjunction(path):
+                            if ignore_errors:
+                                return
+                            raise
+                        cls._rmtree(path, ignore_errors=ignore_errors,
+                                    repeated=(path == name))
+                except FileNotFoundError:
+                    pass
+            elif isinstance(exc, FileNotFoundError):
+                pass
+            else:
+                if not ignore_errors:
+                    raise
+
+        _shutil.rmtree(name, onerror=onexc)
+
+    @classmethod
+    def _cleanup(cls, name, warn_message, ignore_errors=False, delete=True):
+        if delete:
+            cls._rmtree(name, ignore_errors=ignore_errors)
+            _warnings.warn(warn_message, ResourceWarning)
 
     def __repr__(self):
         return "<{} {!r}>".format(self.__class__.__name__, self.name)
@@ -706,8 +823,9 @@ class TemporaryDirectory(object):
         return self.name
 
     def __exit__(self, exc, value, tb):
-        self.cleanup()
+        if self._delete:
+            self.cleanup()
 
     def cleanup(self):
-        if self._finalizer.detach():
-            _shutil.rmtree(self.name)
+        if self._finalizer.detach() or _os.path.exists(self.name):
+            self._rmtree(self.name, ignore_errors=self._ignore_cleanup_errors)
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -119,6 +119,37 @@ class ResourceDenied(unittest.SkipTest):
     and unexpected skips.
     """
 
+_can_symlink = None
+
+TESTFN_ASCII = "{}_{}_tmp".format('@test', os.getpid())
+
+def can_symlink():
+    global _can_symlink
+    if _can_symlink is not None:
+        return _can_symlink
+    # WASI / wasmtime prevents symlinks with absolute paths, see man
+    # openat2(2) RESOLVE_BENEATH. Almost all symlink tests use absolute
+    # paths. Skip symlink tests on WASI for now.
+    src = os.path.abspath(TESTFN)
+    symlink_path = src + "can_symlink"
+    try:
+        os.symlink(src, symlink_path)
+        can = True
+    except (OSError, NotImplementedError, AttributeError):
+        can = False
+    else:
+        os.remove(symlink_path)
+    _can_symlink = can
+    return can
+
+
+def skip_unless_symlink(test):
+    """Skip decorator for tests that require functional symlink"""
+    ok = can_symlink()
+    msg = "Requires functional symlink implementation"
+    return test if ok else unittest.skip(msg)(test)
+
+
 @contextlib.contextmanager
 def _ignore_deprecated_imports(ignore=True):
     """Context manager to suppress package and module deprecation
--- a/Lib/test/test_tempfile.py
+++ b/Lib/test/test_tempfile.py
@@ -83,6 +83,7 @@ class TestExports(BaseTestCase):
             "TMP_MAX" : 1,
             "gettempprefix" : 1,
             "gettempdir" : 1,
+            "gettempdirb" : 1,
             "tempdir" : 1,
             "template" : 1,
             "SpooledTemporaryFile" : 1,
@@ -1154,6 +1155,7 @@ class NulledModules:
             d.clear()
             d.update(c)
 
+
 class TestTemporaryDirectory(BaseTestCase):
     """Test TemporaryDirectory()."""
 
@@ -1214,6 +1216,103 @@ class TestTemporaryDirectory(BaseTestCas
                          "were deleted")
         d2.cleanup()
 
+    @support.skip_unless_symlink
+    def test_cleanup_with_symlink_modes(self):
+        # cleanup() should not follow symlinks when fixing mode bits (#91133)
+        with self.do_create(recurse=0) as d2:
+            file1 = os.path.join(d2, 'file1')
+            open(file1, 'wb').close()
+            dir1 = os.path.join(d2, 'dir1')
+            os.mkdir(dir1)
+            for mode in range(8):
+                mode <<= 6
+                with self.subTest(mode=format(mode, '03o')):
+                    def test(target, target_is_directory):
+                        d1 = self.do_create(recurse=0)
+                        symlink = os.path.join(d1.name, 'symlink')
+                        os.symlink(target, symlink,
+                                   target_is_directory=target_is_directory)
+                        try:
+                            os.chmod(symlink, mode, follow_symlinks=False)
+                        except NotImplementedError:
+                            pass
+                        try:
+                            os.chmod(symlink, mode)
+                        except FileNotFoundError:
+                            pass
+                        os.chmod(d1.name, mode)
+                        d1.cleanup()
+                        self.assertFalse(os.path.exists(d1.name))
+
+                    with self.subTest('nonexisting file'):
+                        test('nonexisting', target_is_directory=False)
+                    with self.subTest('nonexisting dir'):
+                        test('nonexisting', target_is_directory=True)
+
+                    with self.subTest('existing file'):
+                        os.chmod(file1, mode)
+                        old_mode = os.stat(file1).st_mode
+                        test(file1, target_is_directory=False)
+                        new_mode = os.stat(file1).st_mode
+                        self.assertEqual(new_mode, old_mode,
+                                         '%03o != %03o' % (new_mode, old_mode))
+
+                    with self.subTest('existing dir'):
+                        os.chmod(dir1, mode)
+                        old_mode = os.stat(dir1).st_mode
+                        test(dir1, target_is_directory=True)
+                        new_mode = os.stat(dir1).st_mode
+                        self.assertEqual(new_mode, old_mode,
+                                         '%03o != %03o' % (new_mode, old_mode))
+
+    @unittest.skipUnless(hasattr(os, 'chflags'), 'requires os.chflags')
+    @support.skip_unless_symlink
+    def test_cleanup_with_symlink_flags(self):
+        # cleanup() should not follow symlinks when fixing flags (#91133)
+        flags = stat.UF_IMMUTABLE | stat.UF_NOUNLINK
+        self.check_flags(flags)
+
+        with self.do_create(recurse=0) as d2:
+            file1 = os.path.join(d2, 'file1')
+            open(file1, 'wb').close()
+            dir1 = os.path.join(d2, 'dir1')
+            os.mkdir(dir1)
+            def test(target, target_is_directory):
+                d1 = self.do_create(recurse=0)
+                symlink = os.path.join(d1.name, 'symlink')
+                os.symlink(target, symlink,
+                           target_is_directory=target_is_directory)
+                try:
+                    os.chflags(symlink, flags, follow_symlinks=False)
+                except NotImplementedError:
+                    pass
+                try:
+                    os.chflags(symlink, flags)
+                except FileNotFoundError:
+                    pass
+                os.chflags(d1.name, flags)
+                d1.cleanup()
+                self.assertFalse(os.path.exists(d1.name))
+
+            with self.subTest('nonexisting file'):
+                test('nonexisting', target_is_directory=False)
+            with self.subTest('nonexisting dir'):
+                test('nonexisting', target_is_directory=True)
+
+            with self.subTest('existing file'):
+                os.chflags(file1, flags)
+                old_flags = os.stat(file1).st_flags
+                test(file1, target_is_directory=False)
+                new_flags = os.stat(file1).st_flags
+                self.assertEqual(new_flags, old_flags)
+
+            with self.subTest('existing dir'):
+                os.chflags(dir1, flags)
+                old_flags = os.stat(dir1).st_flags
+                test(dir1, target_is_directory=True)
+                new_flags = os.stat(dir1).st_flags
+                self.assertEqual(new_flags, old_flags)
+
     @support.cpython_only
     def test_del_on_collection(self):
         # A TemporaryDirectory is deleted when garbage collected
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-12-01-16-57-44.gh-issue-91133.LKMVCV.rst
@@ -0,0 +1,2 @@
+Fix a bug in :class:`tempfile.TemporaryDirectory` cleanup, which now no longer
+dereferences symlinks when working around file system permission errors.

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File CVE-2023-6597-TempDir-cleaning-symlink.patch of Package python3-doc (Revision ecd125339bb037eb0819c24784fc3163)

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