bpo-32374: m_traverse may be called with m_state=NULL (GH-5140)
Multi-phase initialized modules allow m_traverse to be called while the
module is still being initialized, so module authors may need to account
for that.
(cherry picked from commit c2b0b12d1a137ada1023ab7c10b8d9a0249d95f9)
Co-authored-by: Marcel Plch <gmarcel.plch@gmail.com>
diff --git a/Modules/_testmultiphase.c b/Modules/_testmultiphase.c
index 9b04ebf..8090a48 100644
--- a/Modules/_testmultiphase.c
+++ b/Modules/_testmultiphase.c
@@ -10,6 +10,10 @@
PyObject *x_attr; /* Attributes dictionary */
} ExampleObject;
+typedef struct {
+ PyObject *integer;
+} testmultiphase_state;
+
/* Example methods */
static int
@@ -218,18 +222,21 @@
}
/* Helper for module definitions; there'll be a lot of them */
-#define TEST_MODULE_DEF(name, slots, methods) { \
+
+#define TEST_MODULE_DEF_EX(name, slots, methods, statesize, traversefunc) { \
PyModuleDef_HEAD_INIT, /* m_base */ \
name, /* m_name */ \
PyDoc_STR("Test module " name), /* m_doc */ \
- 0, /* m_size */ \
+ statesize, /* m_size */ \
methods, /* m_methods */ \
slots, /* m_slots */ \
- NULL, /* m_traverse */ \
+ traversefunc, /* m_traverse */ \
NULL, /* m_clear */ \
NULL, /* m_free */ \
}
+#define TEST_MODULE_DEF(name, slots, methods) TEST_MODULE_DEF_EX(name, slots, methods, 0, NULL)
+
PyModuleDef_Slot main_slots[] = {
{Py_mod_exec, execfunc},
{0, NULL},
@@ -613,6 +620,44 @@
return PyModuleDef_Init(&def_exec_unreported_exception);
}
+static int
+bad_traverse(PyObject *self, visitproc visit, void *arg) {
+ testmultiphase_state *m_state;
+
+ m_state = PyModule_GetState(self);
+ Py_VISIT(m_state->integer);
+ return 0;
+}
+
+static int
+execfunc_with_bad_traverse(PyObject *mod) {
+ testmultiphase_state *m_state;
+
+ m_state = PyModule_GetState(mod);
+ if (m_state == NULL) {
+ return -1;
+ }
+
+ m_state->integer = PyLong_FromLong(0x7fffffff);
+ Py_INCREF(m_state->integer);
+
+ return 0;
+}
+
+static PyModuleDef_Slot slots_with_bad_traverse[] = {
+ {Py_mod_exec, execfunc_with_bad_traverse},
+ {0, NULL}
+};
+
+static PyModuleDef def_with_bad_traverse = TEST_MODULE_DEF_EX(
+ "_testmultiphase_with_bad_traverse", slots_with_bad_traverse, NULL,
+ sizeof(testmultiphase_state), bad_traverse);
+
+PyMODINIT_FUNC
+PyInit__testmultiphase_with_bad_traverse(PyObject *spec) {
+ return PyModuleDef_Init(&def_with_bad_traverse);
+}
+
/*** Helper for imp test ***/
static PyModuleDef imp_dummy_def = TEST_MODULE_DEF("imp_dummy", main_slots, testexport_methods);
@@ -622,3 +667,4 @@
{
return PyModuleDef_Init(&imp_dummy_def);
}
+