mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-04 08:59:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 11

[3.11] gh-101037: Fix potential memory underallocation for zeros of int subtypes (GH-101038) (#101219)

Browse source 
gh-101037: Fix potential memory underallocation for zeros of int subtypes (GH-101038)

This PR fixes object allocation in long_subtype_new to ensure that there's at least one digit in all cases, and makes sure that the value of that digit is copied over from the source long.

Needs backport to 3.11, but not any further: the change to require at least one digit was only introduced for Python 3.11.

Fixes GH-101037.
(cherry picked from commit 401fdf9c85)

Co-authored-by: Mark Dickinson <dickinsm@gmail.com>
This commit is contained in:
Miss Islington (bot) 2023-01-21 02:54:09 -08:00 • committed by GitHub
parent 99da75e770
commit d2aaf818ae
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 10 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

5
Objects/longobject.c
View file

@ -5415,6 +5415,11 @@ long_subtype_new(PyTypeObject *type, PyObject *x, PyObject *obase)
n = Py_SIZE(tmp);
if (n < 0)
n = -n;
/* Fast operations for single digit integers (including zero)
* assume that there is always at least one digit present. */
if (n == 0) {
n = 1;
}
newobj = (PyLongObject *)type->tp_alloc(type, n);
if (newobj == NULL) {
Py_DECREF(tmp);