[3.11] gh-106033: Get rid of new occurrences of PyDict_GetItem and Py… (#106040)

serhiy-storchaka · web-flow · commit dbe416b82b8a · 2023-06-24T16:41:02.000-07:00
[3.11] gh-106033: Get rid of new occurrences of PyDict_GetItem and PyObject_HasAttr (GH-106034) These functions are broken by design because they discard any exceptions raised inside, including MemoryError and KeyboardInterrupt. They should not be used in new code.. (cherry picked from commit 1d33d53)
diff --git a/Modules/_hashopenssl.c b/Modules/_hashopenssl.c
@@ -384,14 +384,15 @@ py_digest_by_digestmod(PyObject *module, PyObject *digestmod, enum Py_hash_type
     } else {
         _hashlibstate *state = get_hashlib_state(module);
         // borrowed ref
-        name_obj = PyDict_GetItem(state->constructs, digestmod);
+        name_obj = PyDict_GetItemWithError(state->constructs, digestmod);
     }
     if (name_obj == NULL) {
-        _hashlibstate *state = get_hashlib_state(module);
-        PyErr_Clear();
-        PyErr_Format(
-            state->unsupported_digestmod_error,
-            "Unsupported digestmod %R", digestmod);
+        if (!PyErr_Occurred()) {
+            _hashlibstate *state = get_hashlib_state(module);
+            PyErr_Format(
+                state->unsupported_digestmod_error,
+                "Unsupported digestmod %R", digestmod);
+        }
         return NULL;
     }
 
diff --git a/Objects/exceptions.c b/Objects/exceptions.c
@@ -210,22 +210,21 @@ BaseException_add_note(PyObject *self, PyObject *note)
         return NULL;
     }
 
-    if (!PyObject_HasAttr(self, &_Py_ID(__notes__))) {
-        PyObject *new_notes = PyList_New(0);
-        if (new_notes == NULL) {
+    PyObject *notes;
+    if (_PyObject_LookupAttr(self, &_Py_ID(__notes__), &notes) < 0) {
+        return NULL;
+    }
+    if (notes == NULL) {
+        notes = PyList_New(0);
+        if (notes == NULL) {
             return NULL;
         }
-        if (PyObject_SetAttr(self, &_Py_ID(__notes__), new_notes) < 0) {
-            Py_DECREF(new_notes);
+        if (PyObject_SetAttr(self, &_Py_ID(__notes__), notes) < 0) {
+            Py_DECREF(notes);
             return NULL;
         }
-        Py_DECREF(new_notes);
     }
-    PyObject *notes = PyObject_GetAttr(self, &_Py_ID(__notes__));
-    if (notes == NULL) {
-        return NULL;
-    }
-    if (!PyList_Check(notes)) {
+    else if (!PyList_Check(notes)) {
         Py_DECREF(notes);
         PyErr_SetString(PyExc_TypeError, "Cannot add note: __notes__ is not a list");
         return NULL;
@@ -943,11 +942,11 @@ exceptiongroup_subset(
     PyException_SetContext(eg, PyException_GetContext(orig));
     PyException_SetCause(eg, PyException_GetCause(orig));
 
-    if (PyObject_HasAttr(orig, &_Py_ID(__notes__))) {
-        PyObject *notes = PyObject_GetAttr(orig, &_Py_ID(__notes__));
-        if (notes == NULL) {
-            goto error;
-        }
+    PyObject *notes;
+    if (_PyObject_LookupAttr(orig, &_Py_ID(__notes__), &notes) < 0) {
+        goto error;
+    }
+    if (notes) {
         if (PySequence_Check(notes)) {
             /* Make a copy so the parts have independent notes lists. */
             PyObject *notes_copy = PySequence_List(notes);
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
@@ -1138,15 +1138,13 @@ print_exception_notes(struct exception_print_context *ctx, PyObject *value)
         return 0;
     }
 
-    if (!PyObject_HasAttr(value, &_Py_ID(__notes__))) {
-        return 0;
-    }
-    PyObject *notes = PyObject_GetAttr(value, &_Py_ID(__notes__));
-    if (notes == NULL) {
-        return -1;
+    PyObject *notes;
+    int res = _PyObject_LookupAttr(value, &_Py_ID(__notes__), &notes);
+    if (res <= 0) {
+        return res;
     }
     if (!PySequence_Check(notes)) {
-        int res = 0;
+        res = 0;
         if (write_indented_margin(ctx, f) < 0) {
             res = -1;
         }
