mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-11-25 21:11:09 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 10

bpo-41295: Reimplement the Carlo Verre "hackcheck" (GH-21528)

Browse source 
Walk down the MRO backwards to find the type that originally defined the final `tp_setattro`, then make sure we are not jumping over intermediate C-level bases with the Python-level call.

Automerge-Triggered-By: @gvanrossum
This commit is contained in:
scoder 2020-07-18 23:19:50 +02:00 • committed by GitHub
parent 8ca8a2e8fb
commit c53b310e59
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 60 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

29
Objects/typeobject.c
View file

@ -5961,14 +5961,29 @@ hackcheck(PyObject *self, setattrofunc func, const char *what)
return 1;
}
assert(PyTuple_Check(mro));
Py_ssize_t i, n;
n = PyTuple_GET_SIZE(mro);
for (i = 0; i < n; i++) {
/* Find the (base) type that defined the type's slot function. */
PyTypeObject *defining_type = type;
Py_ssize_t i;
for (i = PyTuple_GET_SIZE(mro) - 1; i >= 0; i--) {
PyTypeObject *base = (PyTypeObject*) PyTuple_GET_ITEM(mro, i);
if (base->tp_setattro == func) {
/* 'func' is the earliest non-Python implementation in the MRO. */
if (base->tp_setattro == slot_tp_setattro) {
/* Ignore Python classes:
they never define their own C-level setattro. */
}
else if (base->tp_setattro == type->tp_setattro) {
defining_type = base;
break;
} else if (base->tp_setattro != slot_tp_setattro) {
}
}
/* Reject calls that jump over intermediate C-level overrides. */
for (PyTypeObject *base = defining_type; base; base = base->tp_base) {
if (base->tp_setattro == func) {
/* 'func' is the right slot function to call. */
break;
}
else if (base->tp_setattro != slot_tp_setattro) {
/* 'base' is not a Python class and overrides 'func'.
Its tp_setattro should be called instead. */
PyErr_Format(PyExc_TypeError,
@ -5978,8 +5993,6 @@ hackcheck(PyObject *self, setattrofunc func, const char *what)
return 0;
}
}
/* Either 'func' is not in the mro (which should fail when checking 'self'),
or it's the right slot function to call. */
return 1;
}