[3.15] gh-159880: Fix handle leak in winreg when audit hook returns failure (GH-159881) (GH-159889)

gh-159880: Fix handle leak in winreg when audit hook returns failure (GH-159881)
(cherry picked from commit af1e030)

Co-authored-by: An Long <aisk@users.noreply.github.com>

Author: miss-islington

Misc/NEWS.d/next/Windows/2026-10-20-21-37-34.gh-issue-159880.eKBiLr.rst

@@ -0,0 +1,3 @@
+Fix a key handle leak in :func:`winreg.CreateKey`,
+:func:`winreg.CreateKeyEx` and :func:`winreg.OpenKey` when the
+``winreg.OpenKey/result`` audit hook fails.

PC/winreg.c

@@ -903,6 +903,7 @@ winreg_CreateKey_impl(PyObject *module, HKEY key, const wchar_t *sub_key)
     }
     if (PySys_Audit("winreg.OpenKey/result", "n",
                     (Py_ssize_t)retKey) < 0) {
+        RegCloseKey(retKey);
         return NULL;
     }
     return retKey;
@@ -955,6 +956,7 @@ winreg_CreateKeyEx_impl(PyObject *module, HKEY key, const wchar_t *sub_key,
     }
     if (PySys_Audit("winreg.OpenKey/result", "n",
                     (Py_ssize_t)retKey) < 0) {
+        RegCloseKey(retKey);
         return NULL;
     }
     return retKey;
@@ -1401,6 +1403,7 @@ winreg_OpenKey_impl(PyObject *module, HKEY key, const wchar_t *sub_key,
     }
     if (PySys_Audit("winreg.OpenKey/result", "n",
                     (Py_ssize_t)retKey) < 0) {
+        RegCloseKey(retKey);
         return NULL;
     }
     return retKey;