bpo-29734: nt._getfinalpathname handle leak (GH-740)
Make sure that failure paths call CloseHandle outside of the function that failed
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index aca445f..9e0bef5 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -2325,6 +2325,62 @@
os.unlink(self.junction)
self.assertFalse(os.path.exists(self.junction))
+@unittest.skipUnless(sys.platform == "win32", "Win32 specific tests")
+class Win32NtTests(unittest.TestCase):
+ def setUp(self):
+ from test import support
+ self.nt = support.import_module('nt')
+ pass
+
+ def tearDown(self):
+ pass
+
+ def test_getfinalpathname_handles(self):
+ try:
+ import ctypes, ctypes.wintypes
+ except ImportError:
+ raise unittest.SkipTest('ctypes module is required for this test')
+
+ kernel = ctypes.WinDLL('Kernel32.dll', use_last_error=True)
+ kernel.GetCurrentProcess.restype = ctypes.wintypes.HANDLE
+
+ kernel.GetProcessHandleCount.restype = ctypes.wintypes.BOOL
+ kernel.GetProcessHandleCount.argtypes = (ctypes.wintypes.HANDLE,
+ ctypes.wintypes.LPDWORD)
+
+ # This is a pseudo-handle that doesn't need to be closed
+ hproc = kernel.GetCurrentProcess()
+
+ handle_count = ctypes.wintypes.DWORD()
+ ok = kernel.GetProcessHandleCount(hproc, ctypes.byref(handle_count))
+ self.assertEqual(1, ok)
+
+ before_count = handle_count.value
+
+ # The first two test the error path, __file__ tests the success path
+ filenames = [ r'\\?\C:',
+ r'\\?\NUL',
+ r'\\?\CONIN',
+ __file__ ]
+
+ for i in range(10):
+ for name in filenames:
+ try:
+ tmp = self.nt._getfinalpathname(name)
+ except:
+ # Failure is expected
+ pass
+ try:
+ tmp = os.stat(name)
+ except:
+ pass
+
+ ok = kernel.GetProcessHandleCount(hproc, ctypes.byref(handle_count))
+ self.assertEqual(1, ok)
+
+ handle_delta = handle_count.value - before_count
+
+ self.assertEqual(0, handle_delta)
@support.skip_unless_symlink
class NonLocalSymlinkTests(unittest.TestCase):
diff --git a/Misc/NEWS.d/next/Windows/2019-01-12-16-52-38.bpo-29734.6_OJwI.rst b/Misc/NEWS.d/next/Windows/2019-01-12-16-52-38.bpo-29734.6_OJwI.rst
new file mode 100644
index 0000000..c89a509
--- /dev/null
+++ b/Misc/NEWS.d/next/Windows/2019-01-12-16-52-38.bpo-29734.6_OJwI.rst
@@ -0,0 +1 @@
+Fix handle leaks in os.stat on Windows.
\ No newline at end of file
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 931c0d3..80add7d 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -1640,11 +1640,6 @@
return FALSE;
}
- if(!CloseHandle(hdl)) {
- PyMem_RawFree(buf);
- return FALSE;
- }
-
buf[result_length] = 0;
*target_path = buf;
@@ -1702,9 +1697,10 @@
return -1;
}
if (info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
- if (!win32_get_reparse_tag(hFile, &reparse_tag))
+ if (!win32_get_reparse_tag(hFile, &reparse_tag)) {
+ CloseHandle(hFile);
return -1;
-
+ }
/* Close the outer open file handle now that we're about to
reopen it with different flags. */
if (!CloseHandle(hFile))
@@ -1721,8 +1717,14 @@
if (hFile2 == INVALID_HANDLE_VALUE)
return -1;
- if (!get_target_path(hFile2, &target_path))
+ if (!get_target_path(hFile2, &target_path)) {
+ CloseHandle(hFile2);
return -1;
+ }
+
+ if (!CloseHandle(hFile2)) {
+ return -1;
+ }
code = win32_xstat_impl(target_path, result, FALSE);
PyMem_RawFree(target_path);