File CVE-2024-12254-unbound-mem-buffering-SelectorSocketTransport.writelines.patch of Package python313

From bfc2e93d755bf496e5ef4cae9609d2823122c909 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Thu, 5 Dec 2024 10:01:10 -0600
Subject: [PATCH 01/10] Ensure writelines pauses the protocol if needed

---
 Lib/asyncio/selector_events.py                                           |    1 
 Lib/test/test_asyncio/test_selector_events.py                            |   12 ++++++++++
 Misc/NEWS.d/next/Security/2024-12-05-21-35-19.gh-issue-127655.xpPoOf.rst |    1 
 3 files changed, 14 insertions(+)

--- a/Lib/asyncio/selector_events.py
+++ b/Lib/asyncio/selector_events.py
@@ -1175,6 +1175,7 @@ class _SelectorSocketTransport(_Selector
         # If the entire buffer couldn't be written, register a write handler
         if self._buffer:
             self._loop._add_writer(self._sock_fd, self._write_ready)
+            self._maybe_pause_protocol()
 
     def can_write_eof(self):
         return True
--- a/Lib/test/test_asyncio/test_selector_events.py
+++ b/Lib/test/test_asyncio/test_selector_events.py
@@ -805,6 +805,18 @@ class SelectorSocketTransportTests(test_
         self.assertTrue(self.sock.send.called)
         self.assertTrue(self.loop.writers)
 
+    def test_writelines_pauses_protocol(self):
+        data = memoryview(b'data')
+        self.sock.send.return_value = 2
+        self.sock.send.fileno.return_value = 7
+
+        transport = self.socket_transport()
+        transport._high_water = 1
+        transport.writelines([data])
+        self.assertTrue(self.protocol.pause_writing.called)
+        self.assertTrue(self.sock.send.called)
+        self.assertTrue(self.loop.writers)
+
     @unittest.skipUnless(selector_events._HAS_SENDMSG, 'no sendmsg')
     def test_write_sendmsg_full(self):
         data = memoryview(b'data')
--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2024-12-05-21-35-19.gh-issue-127655.xpPoOf.rst
@@ -0,0 +1 @@
+Fixed the :class:`!asyncio.selector_events._SelectorSocketTransport` transport not pausing writes for the protocol when the buffer reaches the high water mark when using :meth:`asyncio.WriteTransport.writelines`.