Merge branch 'main' into issue-153252

Author: sobolevn

.github/workflows/build.yml

@@ -554,7 +554,6 @@ jobs:
         - Thread
         free-threading:
         - false
-        - true
         sanitizer:
         - TSan
         include:
@@ -566,6 +565,17 @@ jobs:
       sanitizer: ${{ matrix.sanitizer }}
       free-threading: ${{ matrix.free-threading }}
 
+  # XXX: Temporarily allow this job to fail to not block PRs.
+  build-san-free-threading:
+    # ${{ '' } is a hack to nest jobs under the same sidebar category.
+    name: Sanitizers${{ '' }}  # zizmor: ignore[obfuscation]
+    needs: build-context
+    if: needs.build-context.outputs.run-ubuntu == 'true'
+    uses: ./.github/workflows/reusable-san.yml
+    with:
+      sanitizer: TSan
+      free-threading: true
+
   cross-build-linux:
     name: Cross build Linux
     runs-on: ubuntu-26.04
@@ -669,6 +679,7 @@ jobs:
     - test-hypothesis
     - build-asan
     - build-san
+    - build-san-free-threading
     - cross-build-linux
     - cifuzz
     if: always()
@@ -680,6 +691,7 @@ jobs:
         allowed-failures: >-
           build-android,
           build-emscripten,
+          build-san-free-threading,
           build-windows-msi,
           build-ubuntu-ssltests,
           test-hypothesis,

Lib/test/test_ssl.py

@@ -1604,19 +1604,24 @@ def dummycallback(sock, servername, ctx, cycle=ctx):
         gc.collect()
         self.assertIs(wr(), None)
 
-    @unittest.skipUnless(support.Py_GIL_DISABLED,
-                         "test is only useful if the GIL is disabled")
     @threading_helper.requires_working_threading()
     def test_sni_callback_race(self):
-        # Replacing sni_callback while handshakes are in-flight must not
+        # Replacing sni_callback while a handshake is in-flight must not
         # crash (use-after-free on the callback in free-threaded builds).
+        #
+        # Use a single handshake thread: OpenSSL has internal data races
+        # on shared SSL_CTX state when multiple handshakes run
+        # concurrently against the same context (gh-150191). Concurrency
+        # on the *setter* is what exercises the fix from gh-149816, so
+        # multiple toggler threads race against each other and against
+        # the one handshake worker.
         client_ctx, server_ctx, hostname = testing_context()
 
         server_ctx.sni_callback = lambda *a: None
-        done = threading.Event()
+        deadline = time.monotonic() + 0.1
 
         def do_handshakes():
-            while not done.is_set():
+            while time.monotonic() < deadline:
                 c_in = ssl.MemoryBIO()
                 c_out = ssl.MemoryBIO()
                 s_in = ssl.MemoryBIO()
@@ -1643,19 +1648,11 @@ def do_handshakes():
                         c_in.write(s_out.read())
 
         def toggle_callback():
-            while not done.is_set():
+            while time.monotonic() < deadline:
                 server_ctx.sni_callback = lambda *a: None
                 server_ctx.sni_callback = None
 
-        workers = max(4, (os.cpu_count() or 4) * 2)
-        threads = [threading.Thread(target=do_handshakes)
-                   for _ in range(workers)]
-        threads.append(threading.Thread(target=toggle_callback))
-
-        with threading_helper.catch_threading_exception() as cm:
-            with threading_helper.start_threads(threads):
-                done.set()
-            self.assertIsNone(cm.exc_value)
+        threading_helper.run_concurrently([do_handshakes] + 4 * [toggle_callback])
 
     def test_cert_store_stats(self):
         ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)

Misc/NEWS.d/next/Core_and_Builtins/2026-07-07-04-16-48.gh-issue-153205.5fE8QZ.rst

@@ -0,0 +1,2 @@
+Fix a potential :exc:`SystemError` during vector calls when memory allocation fails.
+A :exc:`MemoryError` is now raised instead.

Python/ceval.c

@@ -1056,6 +1056,7 @@ _PyObjectArray_FromStackRefArray(_PyStackRef *input, Py_ssize_t nargs, PyObject
         // +1 in case PY_VECTORCALL_ARGUMENTS_OFFSET is set.
         result = PyMem_Malloc((nargs + 1) * sizeof(PyObject *));
         if (result == NULL) {
+            PyErr_NoMemory();
             return NULL;
         }
     }