pythongh-122170: Handle ValueError raised by os.stat() in linecache (p…

…ythonGH-122176)

Lib/linecache.py

@@ -70,7 +70,7 @@ def checkcache(filename=None):
  return
  try:
  stat = os.stat(fullname)
- except OSError:
+ except (OSError, ValueError):
  cache.pop(filename, None)
  continue
  if size != stat.st_size or mtime != stat.st_mtime:
@@ -135,10 +135,12 @@ def updatecache(filename, module_globals=None):
  try:
  stat = os.stat(fullname)
  break
- except OSError:
+ except (OSError, ValueError):
  pass
  else:
  return []
+ except ValueError: # may be raised by os.stat()
+ return []
  try:
  with tokenize.open(fullname) as fp:
  lines = fp.readlines()

Lib/test/test_linecache.py

@@ -280,6 +280,37 @@ def test_loader(self):
  self.assertEqual(linecache.getlines(filename, module_globals),
  ['source for x.y.z\n'])
 
+ def test_invalid_names(self):
+ for name, desc in [
+ ('\x00', 'NUL bytes filename'),
+ (__file__ + '\x00', 'filename with embedded NUL bytes'),
+ # A filename with surrogate codes. A UnicodeEncodeError is raised
+ # by os.stat() upon querying, which is a subclass of ValueError.
+ ("\uD834\uDD1E.py", 'surrogate codes (MUSICAL SYMBOL G CLEF)'),
+ # For POSIX platforms, an OSError will be raised but for Windows
+ # platforms, a ValueError is raised due to the path_t converter.
+ # See: https://github.com/python/cpython/issues/122170
+ ('a' * 1_000_000, 'very long filename'),
+ ]:
+ with self.subTest(f'updatecache: {desc}'):
+ linecache.clearcache()
+ lines = linecache.updatecache(name)
+ self.assertListEqual(lines, [])
+ self.assertNotIn(name, linecache.cache)
+
+ # hack into the cache (it shouldn't be allowed
+ # but we never know what people do...)
+ for key, fullname in [(name, 'ok'), ('key', name), (name, name)]:
+ with self.subTest(f'checkcache: {desc}',
+ key=key, fullname=fullname):
+ linecache.clearcache()
+ linecache.cache[key] = (0, 1234, [], fullname)
+ linecache.checkcache(key)
+ self.assertNotIn(key, linecache.cache)
+
+ # just to be sure that we did not mess with cache
+ linecache.clearcache()
+
 
 class LineCacheInvalidationTests(unittest.TestCase):
  def setUp(self):

Misc/NEWS.d/next/Library/2024-07-23-15-30-23.gh-issue-122170.Z9gi3Y.rst

@@ -0,0 +1,2 @@
+Handle :exc:`ValueError`\s raised by :func:`os.stat` in :mod:`linecache`.
+Patch by Bénédikt Tran.