make net_helpers functions work on OpenSUSE

/sbin may not be in the regular user's PATH or tools like sysctl/ss
may require root privileges to execute correctly on OpenSUSE, and this
makes net_helpers functions fail with OSError. There is no harm in
running ss or sysctl as root user for these functions and that allows
fullstack/functional tests to operate correctly on OpenSUSE.

The change requires a testcase to inherit from BaseSudoTestCase due
to the new run_as_root=True flag.

Change-Id: Ia4f2af1d44faacf5f7ab5471b4f18ecb27f06549

neutron/tests/common/net_helpers.py

@@ -189,7 +189,7 @@ def _get_source_ports_from_ss_output(output):
 def get_unused_port(used, start=1024, end=None):
     if end is None:
         port_range = utils.execute(
-            ['sysctl', '-n', 'net.ipv4.ip_local_port_range'])
+            ['sysctl', '-n', 'net.ipv4.ip_local_port_range'], run_as_root=True)
         end = int(port_range.split()[0]) - 1
 
     candidates = set(range(start, end + 1))
@@ -219,7 +219,7 @@ def get_free_namespace_port(protocol, namespace=None, start=1024, end=None):
         raise ValueError("Unsupported protocol %s" % protocol)
 
     ip_wrapper = ip_lib.IPWrapper(namespace=namespace)
-    output = ip_wrapper.netns.execute(['ss', param])
+    output = ip_wrapper.netns.execute(['ss', param], run_as_root=True)
     used_ports = _get_source_ports_from_ss_output(output)
 
     return get_unused_port(used_ports, start, end)

neutron/tests/functional/tests/common/exclusive_resources/test_port.py

@@ -18,7 +18,7 @@ from neutron.tests.common.exclusive_resources import port
 from neutron.tests.functional import base
 
 
-class TestExclusivePort(base.BaseLoggingTestCase):
+class TestExclusivePort(base.BaseSudoTestCase):
     def test_port(self):
         port_1 = self.useFixture(port.ExclusivePort(
             constants.PROTO_NAME_TCP)).port