Limit body framing fix to incomplete chunked trailers

serve/server.py

@@ -4197,7 +4197,7 @@ def body_limit() -> int:
 
 
 class BadBody(Exception):
-    """A request body that cannot be read (malformed, incomplete or oversized): the status and the sentence."""
+    """A request body that cannot be read (a malformed or oversized chunked body): the status and the sentence."""
 
     def __init__(self, status: int, message: str):
         super().__init__(message)
@@ -4289,10 +4289,7 @@ def make_handler(svc: Service):
                 self.close_connection = True               # the body is not read: the connection ends with the answer
                 raise BadBody(413, f"the request body is larger than {limit >> 20} MiB "
                                    "(STRATA_MAX_BODY_MIB raises the limit)")
-            body = self.rfile.read(length)
-            if len(body) != length:
-                raise BadBody(400, "the request body ended early")
-            return body
+            return self.rfile.read(length)
 
         def _drain_body(self):
             """An answer sent before the body was read (a 401, a 403, /load, a method with no handler) must not close
@@ -4603,7 +4600,7 @@ def make_handler(svc: Service):
         def do_POST(self):
             try:
                 self._post()
-            except BadBody as e:                              # a malformed, incomplete or oversized body
+            except BadBody as e:                              # #893: a malformed or oversized chunked body
                 self._json(e.status, {"error": {"type": "invalid_request_error", "message": str(e)}})
 
         def _post(self):

serve/test_chunked_body.py

@@ -1,6 +1,6 @@
 """#893 / #894: a request body sent as Transfer-Encoding: chunked (a relay or proxy) is decoded, on every route that
-reads a body; a malformed or oversized one is a 400 / 413, not an empty body. Incomplete framing must not apply an
-otherwise valid JSON body, for either Content-Length or chunked requests.
+reads a body; a malformed or oversized one is a 400 / 413, not an empty body. Incomplete chunked framing must not
+apply an otherwise valid JSON body.
 
     python -m unittest serve.test_chunked_body -v
 """
@@ -109,10 +109,6 @@ class ChunkedBody(unittest.TestCase):
         status, got = self.send(head, body)
         self.assertEqual((status, self.svc.shared), (400, before), got)
 
-    def test_a_short_content_length_body_does_not_change_settings(self):
-        body = json.dumps({"defaults": {"temperature": 0.5}}).encode()
-        self.assert_settings_body_rejected(b"Content-Length: %d" % (len(body) + 1) + CRLF, body)
-
     def test_incomplete_chunked_trailers_do_not_change_settings(self):
         body = json.dumps({"defaults": {"temperature": 0.5}}).encode()
         prefix = chunked(body)[:-len(CRLF)]                 # the zero chunk, without the terminating blank line