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

[3.13] gh-132713: Fix repr(list) race condition (#132801) (#132809)

Browse source 
Hold a strong reference to the item while calling repr(item).

(cherry picked from commit a4ea80d523)
This commit is contained in:
Victor Stinner 2025-04-23 15:44:33 +02:00 • committed by GitHub
parent 3a130c1786
commit 3de0f55f34
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
3 changed files with 22 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

8
Objects/listobject.c
View file

@ -585,6 +585,7 @@ list_repr_impl(PyListObject *v)
{
PyObject *s;
_PyUnicodeWriter writer;
PyObject *item = NULL;
Py_ssize_t i = Py_ReprEnter((PyObject*)v);
if (i != 0) {
return i > 0 ? PyUnicode_FromString("[...]") : NULL;
@ -601,12 +602,15 @@ list_repr_impl(PyListObject *v)
/* Do repr() on each element. Note that this may mutate the list,
so must refetch the list size on each iteration. */
for (i = 0; i < Py_SIZE(v); ++i) {
/* Hold a strong reference since repr(item) can mutate the list */
item = Py_NewRef(v->ob_item[i]);
if (i > 0) {
if (_PyUnicodeWriter_WriteASCIIString(&writer, ", ", 2) < 0)
goto error;
}
s = PyObject_Repr(v->ob_item[i]);
s = PyObject_Repr(item);
if (s == NULL)
goto error;
@ -615,6 +619,7 @@ list_repr_impl(PyListObject *v)
goto error;
}
Py_DECREF(s);
Py_CLEAR(item);
}
writer.overallocate = 0;
@ -625,6 +630,7 @@ list_repr_impl(PyListObject *v)
return _PyUnicodeWriter_Finish(&writer);
error:
Py_XDECREF(item);
_PyUnicodeWriter_Dealloc(&writer);
Py_ReprLeave((PyObject *)v);
return NULL;