File bpo-37596-make-set-marshalling.patch of Package python39
From 33d95c6facdfda3c8c0feffa7a99184e4abc2f63 Mon Sep 17 00:00:00 2001
From: Brandt Bucher <brandt@python.org>
Date: Wed, 25 Aug 2021 04:14:34 -0700
Subject: [PATCH] bpo-37596: Make `set` and `frozenset` marshalling
deterministic (GH-27926)
---
Lib/test/test_marshal.py | 26 ++++++++
Misc/NEWS.d/next/Library/2021-08-23-21-39-59.bpo-37596.ojRcwB.rst | 2
Python/marshal.c | 32 ++++++++++
3 files changed, 60 insertions(+)
create mode 100644 Misc/NEWS.d/next/Library/2021-08-23-21-39-59.bpo-37596.ojRcwB.rst
--- a/Lib/test/test_marshal.py
+++ b/Lib/test/test_marshal.py
@@ -1,4 +1,5 @@
from test import support
+from test.support.script_helper import assert_python_ok
import array
import io
import marshal
@@ -324,6 +325,31 @@ class BugsTestCase(unittest.TestCase):
for i in range(len(data)):
self.assertRaises(EOFError, marshal.loads, data[0: i])
+ def test_deterministic_sets(self):
+ # bpo-37596: To support reproducible builds, sets and frozensets need to
+ # have their elements serialized in a consistent order (even when they
+ # have been scrambled by hash randomization):
+ for kind in ("set", "frozenset"):
+ for elements in (
+ "float('nan'), b'a', b'b', b'c', 'x', 'y', 'z'",
+ # Also test for bad interactions with backreferencing:
+ "('string', 1), ('string', 2), ('string', 3)",
+ ):
+ s = f"{kind}([{elements}])"
+ with self.subTest(s):
+ # First, make sure that our test case still has different
+ # orders under hash seeds 0 and 1. If this check fails, we
+ # need to update this test with different elements:
+ args = ["-c", f"print({s})"]
+ _, repr_0, _ = assert_python_ok(*args, PYTHONHASHSEED="0")
+ _, repr_1, _ = assert_python_ok(*args, PYTHONHASHSEED="1")
+ self.assertNotEqual(repr_0, repr_1)
+ # Then, perform the actual test:
+ args = ["-c", f"import marshal; print(marshal.dumps({s}))"]
+ _, dump_0, _ = assert_python_ok(*args, PYTHONHASHSEED="0")
+ _, dump_1, _ = assert_python_ok(*args, PYTHONHASHSEED="1")
+ self.assertEqual(dump_0, dump_1)
+
LARGE_SIZE = 2**31
pointer_size = 8 if sys.maxsize > 0xFFFFFFFF else 4
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2021-08-23-21-39-59.bpo-37596.ojRcwB.rst
@@ -0,0 +1,2 @@
+Ensure that :class:`set` and :class:`frozenset` objects are always
+:mod:`marshalled <marshal>` reproducibly.
--- a/Python/marshal.c
+++ b/Python/marshal.c
@@ -502,9 +502,41 @@ w_complex_object(PyObject *v, char flag,
W_TYPE(TYPE_SET, p);
n = PySet_GET_SIZE(v);
W_SIZE(n, p);
+ // bpo-37596: To support reproducible builds, sets and frozensets need
+ // to have their elements serialized in a consistent order (even when
+ // they have been scrambled by hash randomization). To ensure this, we
+ // use an order equivalent to sorted(v, key=marshal.dumps):
+ PyObject *pairs = PyList_New(0);
+ if (pairs == NULL) {
+ p->error = WFERR_NOMEMORY;
+ return;
+ }
while (_PySet_NextEntry(v, &pos, &value, &hash)) {
+ PyObject *dump = PyMarshal_WriteObjectToString(value, p->version);
+ if (dump == NULL) {
+ p->error = WFERR_UNMARSHALLABLE;
+ goto anyset_done;
+ }
+ PyObject *pair = PyTuple_Pack(2, dump, value);
+ Py_DECREF(dump);
+ if (pair == NULL || PyList_Append(pairs, pair)) {
+ p->error = WFERR_NOMEMORY;
+ Py_XDECREF(pair);
+ goto anyset_done;
+ }
+ Py_DECREF(pair);
+ }
+ if (PyList_Sort(pairs)) {
+ p->error = WFERR_NOMEMORY;
+ goto anyset_done;
+ }
+ for (Py_ssize_t i = 0; i < n; i++) {
+ PyObject *pair = PyList_GET_ITEM(pairs, i);
+ value = PyTuple_GET_ITEM(pair, 1);
w_object(value, p);
}
+ anyset_done:
+ Py_DECREF(pairs);
}
else if (PyCode_Check(v)) {
PyCodeObject *co = (PyCodeObject *)v;