yahoo-eng-team team mailing list archive

[OpenStack Infra <1844500@xxxxxxxxxxxxxxxxxx>]

Reviewed:  https://review.opendev.org/682840
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=3330bc01cbdecb12be9c30d78f648710f374d23e
Submitter: Zuul
Branch:    master

commit 3330bc01cbdecb12be9c30d78f648710f374d23e
Author: Jens Harbott <j.harbott@xxxxxxxx>
Date:   Wed Sep 18 08:46:58 2019 +0000

    Fix race condition when getting cmdline
    
    Even though we check for the existence of the process before, it may
    still terminate before we get to read its command line, so catch the
    error that can occur here.
    
    Change-Id: I3e89aca8bedfd2912effe2490718223f7d03133e
    Closes-Bug: 1844500


** Changed in: neutron
       Status: In Progress => Fix Released

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to neutron.
https://bugs.launchpad.net/bugs/1844500

Title:
  get_cmdline_from_pid may fail

Status in neutron:
  Fix Released

Bug description:
  Even though get_cmdline_from_pid() checks for the existence of the PID
  before accessing the cmdline, the process may terminate just in
  between, causing an IOError. So we need to catch that exception.

  From https://zuul.opendev.org/t/openstack/build/3a93ef0d0bbd40dc84758682dbc7b049:
          
  ft1.40: neutron.tests.functional.agent.test_firewall.FirewallTestCase.test_egress_udp_rule(OVS Firewall Driver)_StringException: Traceback (most recent call last):
    File "neutron/tests/base.py", line 180, in func
      return f(self, *args, **kwargs)
    File "neutron/tests/functional/agent/test_firewall.py", line 498, in test_egress_udp_rule
      self._test_rule(self.tester.EGRESS, self.tester.UDP)
    File "neutron/tests/functional/agent/test_firewall.py", line 464, in _test_rule
      direction=direction)
    File "neutron/tests/common/conn_testers.py", line 205, in assert_no_connection
      self.assert_connection(direction, protocol, src_port, dst_port)
    File "neutron/tests/common/conn_testers.py", line 49, in wrap
      return f(self, direction, *args, **kwargs)
    File "neutron/tests/common/conn_testers.py", line 200, in assert_connection
      testing_method(direction, protocol, src_port, dst_port)
    File "neutron/tests/common/conn_testers.py", line 161, in _test_transport_connectivity
      nc_tester.test_connectivity()
    File "neutron/tests/common/net_helpers.py", line 526, in test_connectivity
      self.client_process.writeline(testing_string)
    File "neutron/tests/common/net_helpers.py", line 476, in client_process
      self.establish_connection()
    File "neutron/tests/common/net_helpers.py", line 503, in establish_connection
      self._spawn_server_process()
    File "neutron/tests/common/net_helpers.py", line 489, in _spawn_server_process
      listen=True)
    File "neutron/tests/common/net_helpers.py", line 554, in _spawn_nc_in_namespace
      proc = RootHelperProcess(cmd, namespace=namespace)
    File "neutron/tests/common/net_helpers.py", line 300, in __init__
      self._wait_for_child_process()
    File "neutron/tests/common/net_helpers.py", line 333, in _wait_for_child_process
      "in %d seconds" % (self.cmd, timeout)))
    File "neutron/common/utils.py", line 701, in wait_until_true
      while not predicate():
    File "neutron/tests/common/net_helpers.py", line 325, in child_is_running
      self.pid, self.cmd, run_as_root=True)
    File "neutron/agent/linux/utils.py", line 296, in get_root_helper_child_pid
      if pid_invoked_with_cmdline(pid, expected_cmd):
    File "neutron/agent/linux/utils.py", line 356, in pid_invoked_with_cmdline
      cmd = get_cmdline_from_pid(pid)
    File "neutron/agent/linux/utils.py", line 326, in get_cmdline_from_pid
      with open('/proc/%s/cmdline' % pid, 'r') as f:
  IOError: [Errno 2] No such file or directory: '/proc/2866/cmdline

To manage notifications about this bug go to:
https://bugs.launchpad.net/neutron/+bug/1844500/+subscriptions