File CVE-2024-41671.patch of Package python-Twisted
Index: twisted-24.3.0/src/twisted/web/http.py
===================================================================
--- twisted-24.3.0.orig/src/twisted/web/http.py
+++ twisted-24.3.0/src/twisted/web/http.py
@@ -1973,16 +1973,21 @@ class _ChunkedTransferDecoder:
@returns: C{False}, as there is either insufficient data to continue,
or no data remains.
"""
- if (
- self._receivedTrailerHeadersSize + len(self._buffer)
- > self._maxTrailerHeadersSize
- ):
- raise _MalformedChunkedDataError("Trailer headers data is too long.")
-
eolIndex = self._buffer.find(b"\r\n", self._start)
if eolIndex == -1:
# Still no end of network line marker found.
+ #
+ # Check if we've run up against the trailer size limit: if the next
+ # read contains the terminating CRLF then we'll have this many bytes
+ # of trailers (including the CRLFs).
+ minTrailerSize = (
+ self._receivedTrailerHeadersSize
+ + len(self._buffer)
+ + (1 if self._buffer.endswith(b"\r") else 2)
+ )
+ if minTrailerSize > self._maxTrailerHeadersSize:
+ raise _MalformedChunkedDataError("Trailer headers data is too long.")
# Continue processing more data.
return False
@@ -1992,6 +1997,8 @@ class _ChunkedTransferDecoder:
del self._buffer[0 : eolIndex + 2]
self._start = 0
self._receivedTrailerHeadersSize += eolIndex + 2
+ if self._receivedTrailerHeadersSize > self._maxTrailerHeadersSize:
+ raise _MalformedChunkedDataError("Trailer headers data is too long.")
return True
# eolIndex in this part of code is equal to 0
@@ -2315,8 +2322,8 @@ class HTTPChannel(basic.LineReceiver, po
self.__header = line
def _finishRequestBody(self, data):
- self.allContentReceived()
self._dataBuffer.append(data)
+ self.allContentReceived()
def _maybeChooseTransferDecoder(self, header, data):
"""
Index: twisted-24.3.0/src/twisted/web/newsfragments/12248.bugfix
===================================================================
--- /dev/null
+++ twisted-24.3.0/src/twisted/web/newsfragments/12248.bugfix
@@ -0,0 +1 @@
+The HTTP 1.0 and 1.1 server provided by twisted.web could process pipelined HTTP requests out-of-order, possibly resulting in information disclosure (CVE-2024-41671/GHSA-c8m8-j448-xjx7)
Index: twisted-24.3.0/src/twisted/web/test/test_http.py
===================================================================
--- twisted-24.3.0.orig/src/twisted/web/test/test_http.py
+++ twisted-24.3.0/src/twisted/web/test/test_http.py
@@ -135,7 +135,7 @@ class DummyHTTPHandler(http.Request):
data = self.content.read()
length = self.getHeader(b"content-length")
if length is None:
- length = networkString(str(length))
+ length = str(length).encode()
request = b"'''\n" + length + b"\n" + data + b"'''\n"
self.setResponseCode(200)
self.setHeader(b"Request", self.uri)
@@ -563,17 +563,23 @@ class HTTP0_9Tests(HTTP1_0Tests):
class PipeliningBodyTests(unittest.TestCase, ResponseTestMixin):
"""
- Tests that multiple pipelined requests with bodies are correctly buffered.
+ Pipelined requests get buffered and executed in the order received,
+ not processed in parallel.
"""
requests = (
b"POST / HTTP/1.1\r\n"
b"Content-Length: 10\r\n"
b"\r\n"
- b"0123456789POST / HTTP/1.1\r\n"
- b"Content-Length: 10\r\n"
- b"\r\n"
b"0123456789"
+ # Chunk encoded request.
+ b"POST / HTTP/1.1\r\n"
+ b"Transfer-Encoding: chunked\r\n"
+ b"\r\n"
+ b"a\r\n"
+ b"0123456789\r\n"
+ b"0\r\n"
+ b"\r\n"
)
expectedResponses = [
@@ -590,14 +596,16 @@ class PipeliningBodyTests(unittest.TestC
b"Request: /",
b"Command: POST",
b"Version: HTTP/1.1",
- b"Content-Length: 21",
- b"'''\n10\n0123456789'''\n",
+ b"Content-Length: 23",
+ b"'''\nNone\n0123456789'''\n",
),
]
- def test_noPipelining(self):
+ def test_stepwiseTinyTube(self):
"""
- Test that pipelined requests get buffered, not processed in parallel.
+ Imitate a slow connection that delivers one byte at a time.
+ The request handler (L{DelayedHTTPHandler}) is puppeted to
+ step through the handling of each request.
"""
b = StringTransport()
a = http.HTTPChannel()
@@ -606,10 +614,9 @@ class PipeliningBodyTests(unittest.TestC
# one byte at a time, to stress it.
for byte in iterbytes(self.requests):
a.dataReceived(byte)
- value = b.value()
# So far only one request should have been dispatched.
- self.assertEqual(value, b"")
+ self.assertEqual(b.value(), b"")
self.assertEqual(1, len(a.requests))
# Now, process each request one at a time.
@@ -618,8 +625,95 @@ class PipeliningBodyTests(unittest.TestC
request = a.requests[0].original
request.delayedProcess()
- value = b.value()
- self.assertResponseEquals(value, self.expectedResponses)
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_stepwiseDumpTruck(self):
+ """
+ Imitate a fast connection where several pipelined
+ requests arrive in a single read. The request handler
+ (L{DelayedHTTPHandler}) is puppeted to step through the
+ handling of each request.
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DelayedHTTPHandlerProxy
+ a.makeConnection(b)
+
+ a.dataReceived(self.requests)
+
+ # So far only one request should have been dispatched.
+ self.assertEqual(b.value(), b"")
+ self.assertEqual(1, len(a.requests))
+
+ # Now, process each request one at a time.
+ while a.requests:
+ self.assertEqual(1, len(a.requests))
+ request = a.requests[0].original
+ request.delayedProcess()
+
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_immediateTinyTube(self):
+ """
+ Imitate a slow connection that delivers one byte at a time.
+
+ (L{DummyHTTPHandler}) immediately responds, but no more
+ than one
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DummyHTTPHandlerProxy # "sync"
+ a.makeConnection(b)
+
+ # one byte at a time, to stress it.
+ for byte in iterbytes(self.requests):
+ a.dataReceived(byte)
+ # There is never more than one request dispatched at a time:
+ self.assertLessEqual(len(a.requests), 1)
+
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_immediateDumpTruck(self):
+ """
+ Imitate a fast connection where several pipelined
+ requests arrive in a single read. The request handler
+ (L{DummyHTTPHandler}) immediately responds.
+
+ This doesn't check the at-most-one pending request
+ invariant but exercises otherwise uncovered code paths.
+ See GHSA-c8m8-j448-xjx7.
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DummyHTTPHandlerProxy
+ a.makeConnection(b)
+
+ # All bytes at once to ensure there's stuff to buffer.
+ a.dataReceived(self.requests)
+
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_immediateABiggerTruck(self):
+ """
+ Imitate a fast connection where a so many pipelined
+ requests arrive in a single read that backpressure is indicated.
+ The request handler (L{DummyHTTPHandler}) immediately responds.
+
+ This doesn't check the at-most-one pending request
+ invariant but exercises otherwise uncovered code paths.
+ See GHSA-c8m8-j448-xjx7.
+
+ @see: L{http.HTTPChannel._optimisticEagerReadSize}
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DummyHTTPHandlerProxy
+ a.makeConnection(b)
+
+ overLimitCount = a._optimisticEagerReadSize // len(self.requests) * 10
+ a.dataReceived(self.requests * overLimitCount)
+
+ self.assertResponseEquals(b.value(), self.expectedResponses * overLimitCount)
def test_pipeliningReadLimit(self):
"""
@@ -1522,7 +1616,11 @@ class ChunkedTransferEncodingTests(unitt
lambda b: None, # pragma: nocov
)
p._maxTrailerHeadersSize = 10
- p.dataReceived(b"3\r\nabc\r\n0\r\n0123456789")
+ # 9 bytes are received so far, in 2 packets.
+ # For now, all is ok.
+ p.dataReceived(b"3\r\nabc\r\n0\r\n01234567")
+ p.dataReceived(b"\r")
+ # Once the 10th byte is received, the processing fails.
self.assertRaises(
http._MalformedChunkedDataError,
p.dataReceived,
