[Python-checkins] bpo-38858: Fix ref leak in pycore_interp_init() (GH-17512)

[Victor Stinner]

https://github.com/python/cpython/commit/080ee5a88406fb68aaab741145cd5d2a7c5f2ad6
commit: 080ee5a88406fb68aaab741145cd5d2a7c5f2ad6
branch: master
author: Victor Stinner <vstinner at python.org>
committer: GitHub <noreply at github.com>
date: 2019-12-08T21:55:58+01:00
summary:

bpo-38858: Fix ref leak in pycore_interp_init() (GH-17512)

bpo-38858, bpo-38997: _PySys_Create() returns a strong reference to
the sys module: Py_DECREF() is needed when we are done with the
module.

files:
M Python/pylifecycle.c

diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 8bd71a350de86..823d96e86a438 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -705,24 +705,29 @@ static PyStatus
 pycore_interp_init(PyThreadState *tstate)
 {
     PyStatus status;
+    PyObject *sysmod = NULL;
 
     status = pycore_init_types(tstate);
     if (_PyStatus_EXCEPTION(status)) {
-        return status;
+        goto done;
     }
 
-    PyObject *sysmod;
     status = _PySys_Create(tstate, &sysmod);
     if (_PyStatus_EXCEPTION(status)) {
-        return status;
+        goto done;
     }
 
     status = pycore_init_builtins(tstate);
     if (_PyStatus_EXCEPTION(status)) {
-        return status;
+        goto done;
     }
 
-    return pycore_init_import_warnings(tstate, sysmod);
+    status = pycore_init_import_warnings(tstate, sysmod);
+
+done:
+    /* sys.modules['sys'] contains a strong reference to the module */
+    Py_XDECREF(sysmod);
+    return status;
 }