Public bug reported: During an impish build of ubuntu-cpc images with magic-proxy enabled, the installation of certain packages tried to reach an internet endpoint (specifically http://169.254.169.254/latest/meta-data/instance-id - which appears to be used for EC2 metadata)
The magic-proxy log indicated : 10.10.10.2 - - [01/Oct/2021 13:21:26] urlopen() failed for http://169.254.169.254/2009-04-04/meta-data/instance-id with [Errno 110] Connection timed out 10.10.10.2 - - [01/Oct/2021 13:21:26] code 501, message [Errno 110] Connection timed out 10.10.10.2 - - [01/Oct/2021 13:21:26] "GET /2009-04-04/meta-data/instance-id HTTP/1.1" 501 - ---------------------------------------- Exception occurred during processing of request from ('10.10.10.2', 49672) Traceback (most recent call last): File "/usr/lib/python3.9/urllib/request.py", line 1346, in do_open h.request(req.get_method(), req.selector, req.data, headers, File "/usr/lib/python3.9/http/client.py", line 1279, in request self._send_request(method, url, body, headers, encode_chunked) File "/usr/lib/python3.9/http/client.py", line 1325, in _send_request self.endheaders(body, encode_chunked=encode_chunked) File "/usr/lib/python3.9/http/client.py", line 1274, in endheaders self._send_output(message_body, encode_chunked=encode_chunked) File "/usr/lib/python3.9/http/client.py", line 1034, in _send_output self.send(msg) File "/usr/lib/python3.9/http/client.py", line 974, in send self.connect() File "/usr/lib/python3.9/http/client.py", line 945, in connect self.sock = self._create_connection( File "/usr/lib/python3.9/socket.py", line 844, in create_connection raise err File "/usr/lib/python3.9/socket.py", line 832, in create_connection sock.connect(sa) TimeoutError: [Errno 110] Connection timed out During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/usr/share/livecd-rootfs/magic-proxy", line 873, in __get_request with urllib.request.urlopen( File "/usr/lib/python3.9/urllib/request.py", line 214, in urlopen return opener.open(url, data, timeout) File "/usr/lib/python3.9/urllib/request.py", line 517, in open response = self._open(req, data) File "/usr/lib/python3.9/urllib/request.py", line 534, in _open result = self._call_chain(self.handle_open, protocol, protocol + File "/usr/lib/python3.9/urllib/request.py", line 494, in _call_chain result = func(*args) File "/usr/lib/python3.9/urllib/request.py", line 1375, in http_open return self.do_open(http.client.HTTPConnection, req) File "/usr/lib/python3.9/urllib/request.py", line 1349, in do_open raise URLError(err) urllib.error.URLError: <urlopen error [Errno 110] Connection timed out> During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/usr/lib/python3.9/socketserver.py", line 683, in process_request_thread self.finish_request(request, client_address) File "/usr/lib/python3.9/socketserver.py", line 360, in finish_request self.RequestHandlerClass(request, client_address, self) File "/usr/lib/python3.9/socketserver.py", line 747, in __init__ self.handle() File "/usr/lib/python3.9/http/server.py", line 427, in handle self.handle_one_request() File "/usr/lib/python3.9/http/server.py", line 415, in handle_one_request method() File "/usr/share/livecd-rootfs/magic-proxy", line 787, in do_GET self.__get_request() File "/usr/share/livecd-rootfs/magic-proxy", line 887, in __get_request self.send_error(501, e.reason) File "/usr/lib/python3.9/http/server.py", line 473, in send_error 'message': html.escape(message, quote=False), File "/usr/lib/python3.9/html/__init__.py", line 19, in escape s = s.replace("&", "&") # Must be done first! AttributeError: 'TimeoutError' object has no attribute 'replace' Because magic-proxy is proxying all traffic to port 80, it will intercept these sort of messages. The TimeoutError ends up bubbling up to the serversocket handling code, which will then cause a broken pipe for all future communications, effectively breaking future apt calls from within the build environment. The concrete problem here is that inside magic-proxy, self.send_error is called with the argument of e.reason, which can be a string (no error) or an exception (in case of a nested exception). If the nested exception is passed into self.send_error, html.replace will try to be called on the exception, hence the above exception. In addition to fixing this specific problem, magic-proxy's request handling should catch all exceptions to not interfere with higher up socketserver handling. ** Affects: livecd-rootfs (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1946520 Title: magic-proxy does not gracefully handle error conditions To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/livecd-rootfs/+bug/1946520/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
