diff options
Diffstat (limited to 'py')
| -rw-r--r-- | py/mpconfig.h | 9 | ||||
| -rw-r--r-- | py/runtime.c | 60 |
2 files changed, 66 insertions, 3 deletions
diff --git a/py/mpconfig.h b/py/mpconfig.h index 2d9288f32b..9f541ef705 100644 --- a/py/mpconfig.h +++ b/py/mpconfig.h @@ -393,6 +393,15 @@ typedef double mp_float_t; #define MICROPY_CAN_OVERRIDE_BUILTINS (0) #endif +// Whether to check that the "self" argument of a builtin method has the +// correct type. Such an explicit check is only needed if a builtin +// method escapes to Python land without a first argument, eg +// list.append([], 1). Without this check such calls will have undefined +// behaviour (usually segfault) if the first argument is the wrong type. +#ifndef MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG +#define MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG (1) +#endif + /*****************************************************************************/ /* Fine control over Python builtins, classes, modules, etc */ diff --git a/py/runtime.c b/py/runtime.c index 501ca435a0..4959617eff 100644 --- a/py/runtime.c +++ b/py/runtime.c @@ -887,6 +887,51 @@ mp_obj_t mp_load_attr(mp_obj_t base, qstr attr) { } } +#if MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG + +// The following "checked fun" type is local to the mp_convert_member_lookup +// function, and serves to check that the first argument to a builtin function +// has the correct type. + +typedef struct _mp_obj_checked_fun_t { + mp_obj_base_t base; + const mp_obj_type_t *type; + mp_obj_t fun; +} mp_obj_checked_fun_t; + +STATIC mp_obj_t checked_fun_call(mp_obj_t self_in, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) { + mp_obj_checked_fun_t *self = self_in; + if (n_args > 0) { + const mp_obj_type_t *arg0_type = mp_obj_get_type(args[0]); + if (arg0_type != self->type) { + if (MICROPY_ERROR_REPORTING != MICROPY_ERROR_REPORTING_DETAILED) { + nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, + "argument has wrong type")); + } else { + nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, + "argument should be a '%q' not a '%q'", self->type->name, arg0_type->name)); + } + } + } + return mp_call_function_n_kw(self->fun, n_args, n_kw, args); +} + +STATIC const mp_obj_type_t mp_type_checked_fun = { + { &mp_type_type }, + .name = MP_QSTR_function, + .call = checked_fun_call, +}; + +STATIC mp_obj_t mp_obj_new_checked_fun(const mp_obj_type_t *type, mp_obj_t fun) { + mp_obj_checked_fun_t *o = m_new_obj(mp_obj_checked_fun_t); + o->base.type = &mp_type_checked_fun; + o->type = type; + o->fun = fun; + return o; +} + +#endif // MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG + // Given a member that was extracted from an instance, convert it correctly // and put the result in the dest[] array for a possible method call. // Conversion means dealing with static/class methods, callables, and values. @@ -903,9 +948,18 @@ void mp_convert_member_lookup(mp_obj_t self, const mp_obj_type_t *type, mp_obj_t // Don't try to bind types (even though they're callable) dest[0] = member; } else if (mp_obj_is_callable(member)) { - // return a bound method, with self being this object - dest[0] = member; - dest[1] = self; + #if MICROPY_BUILTIN_METHOD_CHECK_SELF_ARG + if (self == MP_OBJ_NULL && mp_obj_get_type(member) == &mp_type_fun_builtin) { + // we extracted a builtin method without a first argument, so we must + // wrap this function in a type checker + dest[0] = mp_obj_new_checked_fun(type, member); + } else + #endif + { + // return a bound method, with self being this object + dest[0] = member; + dest[1] = self; + } } else { // class member is a value, so just return that value dest[0] = member; |