diff options
| -rw-r--r-- | Doc/library/pathlib.rst | 12 | ||||
| -rw-r--r-- | Lib/pathlib.py | 29 | ||||
| -rw-r--r-- | Lib/test/test_pathlib.py | 54 | ||||
| -rw-r--r-- | Misc/NEWS | 3 |
4 files changed, 81 insertions, 17 deletions
diff --git a/Doc/library/pathlib.rst b/Doc/library/pathlib.rst index 5a81917..34ab3b8 100644 --- a/Doc/library/pathlib.rst +++ b/Doc/library/pathlib.rst @@ -919,7 +919,7 @@ call fails (for example because the path doesn't exist): to an existing file or directory, it will be unconditionally replaced. -.. method:: Path.resolve() +.. method:: Path.resolve(strict=False) Make the path absolute, resolving any symlinks. A new path object is returned:: @@ -936,10 +936,14 @@ call fails (for example because the path doesn't exist): >>> p.resolve() PosixPath('/home/antoine/pathlib/setup.py') - If the path doesn't exist, :exc:`FileNotFoundError` is raised. If an - infinite loop is encountered along the resolution path, - :exc:`RuntimeError` is raised. + If the path doesn't exist and *strict* is ``True``, :exc:`FileNotFoundError` + is raised. If *strict* is ``False``, the path is resolved as far as possible + and any remainder is appended without checking whether it exists. If an + infinite loop is encountered along the resolution path, :exc:`RuntimeError` + is raised. + .. versionadded:: 3.6 + The *strict* argument. .. method:: Path.rglob(pattern) diff --git a/Lib/pathlib.py b/Lib/pathlib.py index 1b5ab38..6965393 100644 --- a/Lib/pathlib.py +++ b/Lib/pathlib.py @@ -178,12 +178,26 @@ class _WindowsFlavour(_Flavour): def casefold_parts(self, parts): return [p.lower() for p in parts] - def resolve(self, path): + def resolve(self, path, strict=False): s = str(path) if not s: return os.getcwd() + previous_s = None if _getfinalpathname is not None: - return self._ext_to_normal(_getfinalpathname(s)) + if strict: + return self._ext_to_normal(_getfinalpathname(s)) + else: + while True: + try: + s = self._ext_to_normal(_getfinalpathname(s)) + except FileNotFoundError: + previous_s = s + s = os.path.abspath(os.path.join(s, os.pardir)) + else: + if previous_s is None: + return s + else: + return s + os.path.sep + os.path.basename(previous_s) # Means fallback on absolute return None @@ -285,7 +299,7 @@ class _PosixFlavour(_Flavour): def casefold_parts(self, parts): return parts - def resolve(self, path): + def resolve(self, path, strict=False): sep = self.sep accessor = path._accessor seen = {} @@ -315,7 +329,10 @@ class _PosixFlavour(_Flavour): target = accessor.readlink(newpath) except OSError as e: if e.errno != EINVAL: - raise + if strict: + raise + else: + return newpath # Not a symlink path = newpath else: @@ -1092,7 +1109,7 @@ class Path(PurePath): obj._init(template=self) return obj - def resolve(self): + def resolve(self, strict=False): """ Make the path absolute, resolving all symlinks on the way and also normalizing it (for example turning slashes into backslashes under @@ -1100,7 +1117,7 @@ class Path(PurePath): """ if self._closed: self._raise_closed() - s = self._flavour.resolve(self) + s = self._flavour.resolve(self, strict=strict) if s is None: # No symlink resolution => for consistency, raise an error if # the path doesn't exist or is forbidden diff --git a/Lib/test/test_pathlib.py b/Lib/test/test_pathlib.py index 2f2ba3c..f98c1fe 100644 --- a/Lib/test/test_pathlib.py +++ b/Lib/test/test_pathlib.py @@ -1486,8 +1486,8 @@ class _BasePathTest(object): self.assertEqual(set(p.glob("../xyzzy")), set()) - def _check_resolve(self, p, expected): - q = p.resolve() + def _check_resolve(self, p, expected, strict=True): + q = p.resolve(strict) self.assertEqual(q, expected) # this can be used to check both relative and absolute resolutions @@ -1498,8 +1498,17 @@ class _BasePathTest(object): P = self.cls p = P(BASE, 'foo') with self.assertRaises(OSError) as cm: - p.resolve() + p.resolve(strict=True) self.assertEqual(cm.exception.errno, errno.ENOENT) + # Non-strict + self.assertEqual(str(p.resolve(strict=False)), + os.path.join(BASE, 'foo')) + p = P(BASE, 'foo', 'in', 'spam') + self.assertEqual(str(p.resolve(strict=False)), + os.path.join(BASE, 'foo')) + p = P(BASE, '..', 'foo', 'in', 'spam') + self.assertEqual(str(p.resolve(strict=False)), + os.path.abspath(os.path.join('foo'))) # These are all relative symlinks p = P(BASE, 'dirB', 'fileB') self._check_resolve_relative(p, p) @@ -1509,6 +1518,18 @@ class _BasePathTest(object): self._check_resolve_relative(p, P(BASE, 'dirB', 'fileB')) p = P(BASE, 'dirB', 'linkD', 'fileB') self._check_resolve_relative(p, P(BASE, 'dirB', 'fileB')) + # Non-strict + p = P(BASE, 'dirA', 'linkC', 'fileB', 'foo', 'in', 'spam') + self._check_resolve_relative(p, P(BASE, 'dirB', 'fileB', 'foo'), False) + p = P(BASE, 'dirA', 'linkC', '..', 'foo', 'in', 'spam') + if os.name == 'nt': + # In Windows, if linkY points to dirB, 'dirA\linkY\..' + # resolves to 'dirA' without resolving linkY first. + self._check_resolve_relative(p, P(BASE, 'dirA', 'foo'), False) + else: + # In Posix, if linkY points to dirB, 'dirA/linkY/..' + # resolves to 'dirB/..' first before resolving to parent of dirB. + self._check_resolve_relative(p, P(BASE, 'foo'), False) # Now create absolute symlinks d = tempfile.mkdtemp(suffix='-dirD') self.addCleanup(support.rmtree, d) @@ -1516,6 +1537,18 @@ class _BasePathTest(object): os.symlink(join('dirB'), os.path.join(d, 'linkY')) p = P(BASE, 'dirA', 'linkX', 'linkY', 'fileB') self._check_resolve_absolute(p, P(BASE, 'dirB', 'fileB')) + # Non-strict + p = P(BASE, 'dirA', 'linkX', 'linkY', 'foo', 'in', 'spam') + self._check_resolve_relative(p, P(BASE, 'dirB', 'foo'), False) + p = P(BASE, 'dirA', 'linkX', 'linkY', '..', 'foo', 'in', 'spam') + if os.name == 'nt': + # In Windows, if linkY points to dirB, 'dirA\linkY\..' + # resolves to 'dirA' without resolving linkY first. + self._check_resolve_relative(p, P(d, 'foo'), False) + else: + # In Posix, if linkY points to dirB, 'dirA/linkY/..' + # resolves to 'dirB/..' first before resolving to parent of dirB. + self._check_resolve_relative(p, P(BASE, 'foo'), False) @with_symlinks def test_resolve_dot(self): @@ -1525,7 +1558,11 @@ class _BasePathTest(object): self.dirlink(os.path.join('0', '0'), join('1')) self.dirlink(os.path.join('1', '1'), join('2')) q = p / '2' - self.assertEqual(q.resolve(), p) + self.assertEqual(q.resolve(strict=True), p) + r = q / '3' / '4' + self.assertRaises(FileNotFoundError, r.resolve, strict=True) + # Non-strict + self.assertEqual(r.resolve(strict=False), p / '3') def test_with(self): p = self.cls(BASE) @@ -1972,10 +2009,10 @@ class PathTest(_BasePathTest, unittest.TestCase): class PosixPathTest(_BasePathTest, unittest.TestCase): cls = pathlib.PosixPath - def _check_symlink_loop(self, *args): + def _check_symlink_loop(self, *args, strict=True): path = self.cls(*args) with self.assertRaises(RuntimeError): - print(path.resolve()) + print(path.resolve(strict)) def test_open_mode(self): old_mask = os.umask(0) @@ -2008,7 +2045,6 @@ class PosixPathTest(_BasePathTest, unittest.TestCase): @with_symlinks def test_resolve_loop(self): - # Loop detection for broken symlinks under POSIX # Loops with relative symlinks os.symlink('linkX/inside', join('linkX')) self._check_symlink_loop(BASE, 'linkX') @@ -2016,6 +2052,8 @@ class PosixPathTest(_BasePathTest, unittest.TestCase): self._check_symlink_loop(BASE, 'linkY') os.symlink('linkZ/../linkZ', join('linkZ')) self._check_symlink_loop(BASE, 'linkZ') + # Non-strict + self._check_symlink_loop(BASE, 'linkZ', 'foo', strict=False) # Loops with absolute symlinks os.symlink(join('linkU/inside'), join('linkU')) self._check_symlink_loop(BASE, 'linkU') @@ -2023,6 +2061,8 @@ class PosixPathTest(_BasePathTest, unittest.TestCase): self._check_symlink_loop(BASE, 'linkV') os.symlink(join('linkW/../linkW'), join('linkW')) self._check_symlink_loop(BASE, 'linkW') + # Non-strict + self._check_symlink_loop(BASE, 'linkW', 'foo', strict=False) def test_glob(self): P = self.cls @@ -23,6 +23,9 @@ Core and Builtins Library ------- +- Issue #19717: Makes Path.resolve() succeed on paths that do not exist. + Patch by Vajrasky Kok + - Issue #28563: Fixed possible DoS and arbitrary code execution when handle plural form selections in the gettext module. The expression parser now supports exact syntax supported by GNU gettext. |