[3.11] gh-105375: Improve _pickle error handling (#105475) (#105583)

(cherry picked from commit 89aac6f6b7)

Error handling was deferred in some cases, which could potentially lead
to exceptions being overwritten.
This commit is contained in:
Erlend E. Aasland 2023-06-09 19:56:02 +02:00 committed by GitHub
parent 90e357bc8a
commit 4d4251d6ec
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 28 additions and 12 deletions

View file

@ -0,0 +1 @@
Fix bugs in :mod:`pickle` where exceptions could be overwritten.

View file

@ -1139,10 +1139,13 @@ _Pickler_New(void)
self->reducer_override = NULL;
self->memo = PyMemoTable_New();
if (self->memo == NULL) {
Py_DECREF(self);
return NULL;
}
self->output_buffer = PyBytes_FromStringAndSize(NULL,
self->max_output_len);
if (self->memo == NULL || self->output_buffer == NULL) {
if (self->output_buffer == NULL) {
Py_DECREF(self);
return NULL;
}
@ -1627,9 +1630,12 @@ _Unpickler_New(void)
self->memo_size = 32;
self->memo_len = 0;
self->memo = _Unpickler_NewMemo(self->memo_size);
if (self->memo == NULL) {
Py_DECREF(self);
return NULL;
}
self->stack = (Pdata *)Pdata_New();
if (self->memo == NULL || self->stack == NULL) {
if (self->stack == NULL) {
Py_DECREF(self);
return NULL;
}
@ -4833,11 +4839,12 @@ _pickle_PicklerMemoProxy_copy_impl(PicklerMemoProxyObject *self)
PyObject *key, *value;
key = PyLong_FromVoidPtr(entry.me_key);
if (key == NULL) {
goto error;
}
value = Py_BuildValue("nO", entry.me_value, entry.me_key);
if (key == NULL || value == NULL) {
Py_XDECREF(key);
Py_XDECREF(value);
if (value == NULL) {
Py_DECREF(key);
goto error;
}
status = PyDict_SetItem(new_memo, key, value);
@ -6033,13 +6040,21 @@ load_stack_global(UnpicklerObject *self)
PyObject *global_name;
PDATA_POP(self->stack, global_name);
if (global_name == NULL) {
return -1;
}
PDATA_POP(self->stack, module_name);
if (module_name == NULL || !PyUnicode_CheckExact(module_name) ||
global_name == NULL || !PyUnicode_CheckExact(global_name)) {
if (module_name == NULL) {
Py_DECREF(global_name);
return -1;
}
if (!PyUnicode_CheckExact(module_name) ||
!PyUnicode_CheckExact(global_name))
{
PickleState *st = _Pickle_GetGlobalState();
PyErr_SetString(st->UnpicklingError, "STACK_GLOBAL requires str");
Py_XDECREF(global_name);
Py_XDECREF(module_name);
Py_DECREF(global_name);
Py_DECREF(module_name);
return -1;
}
global = find_class(self, module_name, global_name);