Skip to content

[3.14] gh-149816: Fix race condition in memoryview with free-threading (GH-149858) #149876

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
sobolevn merged 1 commit into from
May 15, 2026
Merged

[3.14] gh-149816: Fix race condition in memoryview with free-threading (GH-149858) #149876

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions Misc/NEWS.d/next/Core_and_Builtins/2026-05-15-11-31-57.gh-issue-149816.ugN2rx.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
Fix a race condition in :class:`memoryview` with free-threading.
20 changes: 6 additions & 14 deletions Objects/memoryobject.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1600,11 +1600,7 @@ memory_getbuf(PyObject *_self, Py_buffer *view, int flags)


view->obj = Py_NewRef(self);
#ifdef Py_GIL_DISABLED
_Py_atomic_add_ssize(&self->exports, 1);
#else
self->exports++;
#endif
FT_ATOMIC_ADD_SSIZE(self->exports, 1);

return 0;
}
Expand All @@ -1613,11 +1609,7 @@ static void
memory_releasebuf(PyObject *_self, Py_buffer *view)
{
PyMemoryViewObject *self = (PyMemoryViewObject *)_self;
#ifdef Py_GIL_DISABLED
_Py_atomic_add_ssize(&self->exports, -1);
#else
self->exports--;
#endif
FT_ATOMIC_ADD_SSIZE(self->exports, -1);
return;
/* PyBuffer_Release() decrements view->obj after this function returns. */
}
Expand Down Expand Up @@ -2356,9 +2348,9 @@ memoryview_hex_impl(PyMemoryViewObject *self, PyObject *sep,
// Prevent 'self' from being freed if computing len(sep) mutates 'self'
// in _Py_strhex_with_sep().
// See: https://github.com/python/cpython/issues/143195.
self->exports++;
FT_ATOMIC_ADD_SSIZE(self->exports, 1);
PyObject *ret = _Py_strhex_with_sep(src->buf, src->len, sep, bytes_per_sep);
self->exports--;
FT_ATOMIC_ADD_SSIZE(self->exports, -1);
return ret;
}

Expand Down Expand Up @@ -3235,9 +3227,9 @@ memory_hash(PyObject *_self)
if (view->obj != NULL) {
// Prevent 'self' from being freed when computing the item's hash.
// See https://github.com/python/cpython/issues/142664.
self->exports++;
FT_ATOMIC_ADD_SSIZE(self->exports, 1);
Py_hash_t h = PyObject_Hash(view->obj);
self->exports--;
FT_ATOMIC_ADD_SSIZE(self->exports, -1);
if (h == -1) {
/* Keep the original error message */
return -1;
Expand Down
Loading