From b45c8c17f0f295e919a90659d4c1880a47b228c1 Mon Sep 17 00:00:00 2001 From: Damien George Date: Wed, 7 Feb 2018 15:44:29 +1100 Subject: [PATCH] py/objtype: Check and prevent delete/store on a fixed locals map. Note that the check for elem!=NULL is removed for the MP_MAP_LOOKUP_ADD_IF_NOT_FOUND case because mp_map_lookup will always return non-NULL for such a case. --- py/objtype.c | 12 ++++++------ tests/basics/del_attr.py | 7 +++++++ tests/basics/setattr1.py | 7 +++++++ 3 files changed, 20 insertions(+), 6 deletions(-) diff --git a/py/objtype.c b/py/objtype.c index 33757287ac..7df349ce9b 100644 --- a/py/objtype.c +++ b/py/objtype.c @@ -975,21 +975,21 @@ STATIC void type_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) { if (self->locals_dict != NULL) { assert(self->locals_dict->base.type == &mp_type_dict); // MicroPython restriction, for now mp_map_t *locals_map = &self->locals_dict->map; + if (locals_map->is_fixed) { + // can't apply delete/store to a fixed map + return; + } if (dest[1] == MP_OBJ_NULL) { // delete attribute mp_map_elem_t *elem = mp_map_lookup(locals_map, MP_OBJ_NEW_QSTR(attr), MP_MAP_LOOKUP_REMOVE_IF_FOUND); - // note that locals_map may be in ROM, so remove will fail in that case if (elem != NULL) { dest[0] = MP_OBJ_NULL; // indicate success } } else { // store attribute mp_map_elem_t *elem = mp_map_lookup(locals_map, MP_OBJ_NEW_QSTR(attr), MP_MAP_LOOKUP_ADD_IF_NOT_FOUND); - // note that locals_map may be in ROM, so add will fail in that case - if (elem != NULL) { - elem->value = dest[1]; - dest[0] = MP_OBJ_NULL; // indicate success - } + elem->value = dest[1]; + dest[0] = MP_OBJ_NULL; // indicate success } } } diff --git a/tests/basics/del_attr.py b/tests/basics/del_attr.py index bec7afb848..8487b97e31 100644 --- a/tests/basics/del_attr.py +++ b/tests/basics/del_attr.py @@ -30,3 +30,10 @@ try: del c.x except AttributeError: print("AttributeError") + +# try to del an attribute of a built-in class +try: + del int.to_bytes +except (AttributeError, TypeError): + # uPy raises AttributeError, CPython raises TypeError + print('AttributeError/TypeError') diff --git a/tests/basics/setattr1.py b/tests/basics/setattr1.py index 9693aca819..e4acb14cac 100644 --- a/tests/basics/setattr1.py +++ b/tests/basics/setattr1.py @@ -16,3 +16,10 @@ try: setattr(a, b'var3', 1) except TypeError: print('TypeError') + +# try setattr on a built-in function +try: + setattr(int, 'to_bytes', 1) +except (AttributeError, TypeError): + # uPy raises AttributeError, CPython raises TypeError + print('AttributeError/TypeError')