From 3e8ab5c7fc1172f3cdf3c7441807358dcef7cfed Mon Sep 17 00:00:00 2001 From: liningjie Date: Tue, 29 Oct 2024 10:27:41 +0800 Subject: [PATCH] Fix CVE-2024-49768 (cherry picked from commit 5af4633e2f3117ae86c489674a2e0cf597f204f4) --- backport-CVE-2024-49768.patch | 346 ++++++++++++++++++++++++++++++++++ python-waitress.spec | 10 +- 2 files changed, 354 insertions(+), 2 deletions(-) create mode 100644 backport-CVE-2024-49768.patch diff --git a/backport-CVE-2024-49768.patch b/backport-CVE-2024-49768.patch new file mode 100644 index 0000000..ccea972 --- /dev/null +++ b/backport-CVE-2024-49768.patch @@ -0,0 +1,346 @@ +From 6943dcf556610ece2ff3cddb39e59a05ef110661 Mon Sep 17 00:00:00 2001 +From: Delta Regeer +Date: Sat, 26 Oct 2024 22:10:36 -0600 +Subject: [PATCH 1/4] Make DummySock() look more like an actual socket + +This forces DummySock() to look like a properly connected socket where +there is a buffer that is read from by the remote, and a buffer that is +written to by the remote. + +The local side does the opposite, this way data written by the local +side can be read by the remote without operating on the same buffer. +--- + tests/test_channel.py | 57 +++++++++++++++++++++++++++++++++---------- + 1 file changed, 44 insertions(+), 13 deletions(-) + +diff --git a/tests/test_channel.py b/tests/test_channel.py +index 8467ae7..7d677e9 100644 +--- a/tests/test_channel.py ++++ b/tests/test_channel.py +@@ -18,7 +18,7 @@ class TestHTTPChannel(unittest.TestCase): + map = {} + inst = self._makeOne(sock, "127.0.0.1", adj, map=map) + inst.outbuf_lock = DummyLock() +- return inst, sock, map ++ return inst, sock.local(), map + + def test_ctor(self): + inst, _, map = self._makeOneWithMap() +@@ -218,7 +218,7 @@ class TestHTTPChannel(unittest.TestCase): + def send(_): + return 0 + +- sock.send = send ++ sock.remote.send = send + + wrote = inst.write_soon(b"a") + self.assertEqual(wrote, 1) +@@ -236,7 +236,7 @@ class TestHTTPChannel(unittest.TestCase): + def send(_): + return 0 + +- sock.send = send ++ sock.remote.send = send + + outbufs = inst.outbufs + wrote = inst.write_soon(wrapper) +@@ -270,7 +270,7 @@ class TestHTTPChannel(unittest.TestCase): + def send(_): + return 0 + +- sock.send = send ++ sock.remote.send = send + + inst.adj.outbuf_high_watermark = 3 + inst.current_outbuf_count = 4 +@@ -286,7 +286,7 @@ class TestHTTPChannel(unittest.TestCase): + def send(_): + return 0 + +- sock.send = send ++ sock.remote.send = send + + inst.adj.outbuf_high_watermark = 3 + inst.total_outbufs_len = 4 +@@ -315,7 +315,7 @@ class TestHTTPChannel(unittest.TestCase): + inst.connected = False + raise Exception() + +- sock.send = send ++ sock.remote.send = send + + inst.adj.outbuf_high_watermark = 3 + inst.total_outbufs_len = 4 +@@ -345,7 +345,7 @@ class TestHTTPChannel(unittest.TestCase): + inst.connected = False + raise Exception() + +- sock.send = send ++ sock.remote.send = send + + wrote = inst.write_soon(b"xyz") + self.assertEqual(wrote, 3) +@@ -376,7 +376,7 @@ class TestHTTPChannel(unittest.TestCase): + inst.total_outbufs_len = len(inst.outbufs[0]) + inst.adj.send_bytes = 1 + inst.adj.outbuf_high_watermark = 2 +- sock.send = lambda x, do_close=True: False ++ sock.remote.send = lambda x, do_close=True: False + inst.will_close = False + inst.last_activity = 0 + result = inst.handle_write() +@@ -400,7 +400,7 @@ class TestHTTPChannel(unittest.TestCase): + + def test__flush_some_full_outbuf_socket_returns_zero(self): + inst, sock, map = self._makeOneWithMap() +- sock.send = lambda x: False ++ sock.remote.send = lambda x: False + inst.outbufs[0].append(b"abc") + inst.total_outbufs_len = sum(len(x) for x in inst.outbufs) + result = inst._flush_some() +@@ -907,7 +907,8 @@ class DummySock: + closed = False + + def __init__(self): +- self.sent = b"" ++ self.local_sent = b"" ++ self.remote_sent = b"" + + def setblocking(self, *arg): + self.blocking = True +@@ -925,14 +926,44 @@ class DummySock: + self.closed = True + + def send(self, data): +- self.sent += data ++ self.remote_sent += data + return len(data) + + def recv(self, buffer_size): +- result = self.sent[:buffer_size] +- self.sent = self.sent[buffer_size:] ++ result = self.local_sent[:buffer_size] ++ self.local_sent = self.local_sent[buffer_size:] + return result + ++ def local(self): ++ outer = self ++ ++ class LocalDummySock: ++ def send(self, data): ++ outer.local_sent += data ++ return len(data) ++ ++ def recv(self, buffer_size): ++ result = outer.remote_sent[:buffer_size] ++ outer.remote_sent = outer.remote_sent[buffer_size:] ++ return result ++ ++ def close(self): ++ outer.closed = True ++ ++ @property ++ def sent(self): ++ return outer.remote_sent ++ ++ @property ++ def closed(self): ++ return outer.closed ++ ++ @property ++ def remote(self): ++ return outer ++ ++ return LocalDummySock() ++ + + class DummyLock: + notified = False +-- +Gitee + + +From 7e7f11e61d358ab1cb853fcadf2b46b1f00f5993 Mon Sep 17 00:00:00 2001 +From: Delta Regeer +Date: Sat, 26 Oct 2024 22:12:14 -0600 +Subject: [PATCH 2/4] Add a new test to validate the lookahead race condition + +--- + tests/test_channel.py | 55 ++++++++++++++++++++++++++++++++++++++++++- + 1 file changed, 54 insertions(+), 1 deletion(-) + +diff --git a/tests/test_channel.py b/tests/test_channel.py +index 7d677e9..d798091 100644 +--- a/tests/test_channel.py ++++ b/tests/test_channel.py +@@ -805,11 +805,12 @@ class TestHTTPChannelLookahead(TestHTTPChannel): + ) + return [body] + +- def _make_app_with_lookahead(self): ++ def _make_app_with_lookahead(self, recv_bytes=8192): + """ + Setup a channel with lookahead and store it and the socket in self + """ + adj = DummyAdjustments() ++ adj.recv_bytes = recv_bytes + adj.channel_request_lookahead = 5 + channel, sock, map = self._makeOneWithMap(adj=adj) + channel.server.application = self.app_check_disconnect +@@ -901,6 +902,58 @@ class TestHTTPChannelLookahead(TestHTTPChannel): + self.assertEqual(data.split("\r\n")[-1], "finished") + self.assertEqual(self.request_body, b"x") + ++ def test_lookahead_bad_request_drop_extra_data(self): ++ """ ++ Send two requests, the first one being bad, split on the recv_bytes ++ limit, then emulate a race that could happen whereby we read data from ++ the socket while the service thread is cleaning up due to an error ++ processing the request. ++ """ ++ ++ invalid_request = [ ++ "GET / HTTP/1.1", ++ "Host: localhost:8080", ++ "Content-length: -1", ++ "", ++ ] ++ ++ invalid_request_len = len("".join([x + "\r\n" for x in invalid_request])) ++ ++ second_request = [ ++ "POST / HTTP/1.1", ++ "Host: localhost:8080", ++ "Content-Length: 1", ++ "", ++ "x", ++ ] ++ ++ full_request = invalid_request + second_request ++ ++ self._make_app_with_lookahead(recv_bytes=invalid_request_len) ++ self._send(*full_request) ++ self.channel.handle_read() ++ self.assertEqual(len(self.channel.requests), 1) ++ self.channel.server.tasks[0].service() ++ self.assertTrue(self.channel.close_when_flushed) ++ # Read all of the next request ++ self.channel.handle_read() ++ self.channel.handle_read() ++ # Validate that there is no more data to be read ++ self.assertEqual(self.sock.remote.local_sent, b"") ++ # Validate that we dropped the data from the second read, and did not ++ # create a new request ++ self.assertEqual(len(self.channel.requests), 0) ++ data = self.sock.recv(256).decode("ascii") ++ self.assertFalse(self.channel.readable()) ++ self.assertTrue(self.channel.writable()) ++ ++ # Handle the write, which will close the socket ++ self.channel.handle_write() ++ self.assertTrue(self.sock.closed) ++ ++ data = self.sock.recv(256) ++ self.assertEqual(len(data), 0) ++ + + class DummySock: + blocking = False +-- +Gitee + + +From f4ba1c260cf17156b582c6252496213ddc96b591 Mon Sep 17 00:00:00 2001 +From: Delta Regeer +Date: Sat, 26 Oct 2024 22:13:08 -0600 +Subject: [PATCH 3/4] Fix a race condition on recv_bytes boundary when request + is invalid + +A remote client may send a request that is exactly recv_bytes long, +followed by a secondary request using HTTP pipelining. + +When request lookahead is disabled (default) we won't read any more +requests, and when the first request fails due to a parsing error, we +simply close the connection. + +However when request lookahead is enabled, it is possible to process and +receive the first request, start sending the error message back to the +client while we read the next request and queue it. This will allow the +secondar request to be serviced by the worker thread while the +connection should be closed. + +The fix here checks if we should not have read the data in the first +place (because the conection is going to be torn down) while we hold the +`requests_lock` which means the service thread can't be in the middle of +flipping the `close_when_flushed` flag. +--- + src/waitress/channel.py | 11 ++++++++++- + 1 file changed, 10 insertions(+), 1 deletion(-) + +diff --git a/src/waitress/channel.py b/src/waitress/channel.py +index 3860ed5..f4d9677 100644 +--- a/src/waitress/channel.py ++++ b/src/waitress/channel.py +@@ -140,7 +140,7 @@ class HTTPChannel(wasyncore.dispatcher): + # 1. We're not already about to close the connection. + # 2. We're not waiting to flush remaining data before closing the + # connection +- # 3. There are not too many tasks already queued ++ # 3. There are not too many tasks already queued (if lookahead is enabled) + # 4. There's no data in the output buffer that needs to be sent + # before we potentially create a new task. + +@@ -196,6 +196,15 @@ class HTTPChannel(wasyncore.dispatcher): + return False + + with self.requests_lock: ++ # Don't bother processing anymore data if this connection is about ++ # to close. This may happen if readable() returned True, on the ++ # main thread before the service thread set the close_when_flushed ++ # flag, and we read data but our service thread is attempting to ++ # shut down the connection due to an error. We want to make sure we ++ # do this while holding the request_lock so that we can't race ++ if self.will_close or self.close_when_flushed: ++ return False ++ + while data: + if self.request is None: + self.request = self.parser_class(self.adj) +-- +Gitee + + +From 810a435f9e9e293bd3446a5ce2df86f59c4e7b1b Mon Sep 17 00:00:00 2001 +From: Delta Regeer +Date: Sat, 26 Oct 2024 22:22:32 -0600 +Subject: [PATCH 4/4] Add documentation for channel_request_lookahead + +--- + docs/arguments.rst | 14 ++++++++++++++ + 1 file changed, 14 insertions(+) + +diff --git a/docs/arguments.rst b/docs/arguments.rst +index 0b6ca45..b8a856a 100644 +--- a/docs/arguments.rst ++++ b/docs/arguments.rst +@@ -314,3 +314,17 @@ url_prefix + be stripped of the prefix. + + Default: ``''`` ++ ++channel_request_lookahead ++ Sets the amount of requests we can continue to read from the socket, while ++ we are processing current requests. The default value won't allow any ++ lookahead, increase it above ``0`` to enable. ++ ++ When enabled this inserts a callable ``waitress.client_disconnected`` into ++ the environment that allows the task to check if the client disconnected ++ while waiting for the response at strategic points in the execution and to ++ cancel the operation. ++ ++ Default: ``0`` ++ ++ .. versionadded:: 2.0.0 +-- +Gitee + diff --git a/python-waitress.spec b/python-waitress.spec index 48dfa0d..5d300ac 100644 --- a/python-waitress.spec +++ b/python-waitress.spec @@ -1,11 +1,14 @@ %global _empty_manifest_terminate_build 0 Name: python-waitress Version: 2.1.2 -Release: 1 +Release: 2 Summary: Waitress WSGI server License: ZPLv2.1 URL: https://github.com/Pylons/waitress Source0: https://files.pythonhosted.org/packages/72/83/c3de9799e2305898b02ea67bcd125ad06f271e2a82cc86fe66b7bf4e6f63/waitress-2.1.2.tar.gz + +Patch0001: backport-CVE-2024-49768.patch + BuildArch: noarch Requires: python3-Sphinx @@ -45,7 +48,7 @@ is also known to run on PyPy 3 (version 3.7 compatible python) on UNIX. It supports HTTP/1.0 and HTTP/1.1. %prep -%autosetup -n waitress-%{version} +%autosetup -n waitress-%{version} -p1 %build %py3_build @@ -85,6 +88,9 @@ mv %{buildroot}/doclist.lst . %{_docdir}/* %changelog +* Tue Oct 29 2024 liningjie - 2.1.2-2 +- Fix CVE-2024-49768 + * Wed Sep 28 2022 guozhengxin - 2.1.2-1 - Upgrade package to version 2.1.2