Remove 'ln' command from rootwrap filter

Remove 'ln' command from rootwrap filter and oslo.privsep.

Change-Id: I78307620d4dd350656c3350aace2069c9929e850
Signed-off-by: Chuck Short <chucks@redhat.com>

cinder/backup/drivers/tsm.py

@@ -37,6 +37,7 @@ from cinder.backup import driver
 from cinder import exception
 from cinder.i18n import _
 from cinder import interface
+import cinder.privsep.path
 from cinder import utils
 
 LOG = logging.getLogger(__name__)
@@ -108,9 +109,7 @@ def _make_link(volume_path, backup_path, vol_id):
     """
 
     try:
-        utils.execute('ln', volume_path, backup_path,
+        cinder.privsep.path.symlink(volume_path, backup_path)
-                      run_as_root=True,
-                      check_exit_code=True)
     except processutils.ProcessExecutionError as exc:
         err = (_('backup: %(vol_id)s failed to create device hardlink '
                  'from %(vpath)s to %(bpath)s.\n'

cinder/privsep/path.py

@@ -45,3 +45,10 @@ def touch(path):
         os.utime(path, None)
     else:
         open(path, 'a').close()
+
+
+@cinder.privsep.sys_admin_pctxt.entrypoint
+def symlink(src, dest):
+    if not os.path.exists(src):
+        raise exception.FileNotFound(file_path=src)
+    os.symlink(src, dest)

cinder/tests/unit/backup/drivers/test_backup_tsm.py

@@ -265,7 +265,8 @@ class BackupTSMTestCase(test.TestCase):
         return db.backup_create(self.ctxt, backup)['id']
 
     @mock.patch.object(tsm.os, 'stat', fake_stat_image)
-    def test_backup_image(self):
+    @mock.patch('cinder.privsep.path.symlink')
+    def test_backup_image(self, mock_symlink):
         volume_id = fake.VOLUME_ID
         mode = 'image'
         self._create_volume_db_entry(volume_id)
@@ -299,7 +300,8 @@ class BackupTSMTestCase(test.TestCase):
             self.driver.delete_backup(backup1)
 
     @mock.patch.object(tsm.os, 'stat', fake_stat_file)
-    def test_backup_file(self):
+    @mock.patch('cinder.privsep.path.symlink')
+    def test_backup_file(self, mock_symlink):
         volume_id = fake.VOLUME_ID
         mode = 'file'
         self._create_volume_db_entry(volume_id)

cinder/tests/unit/volume/drivers/test_veritas_cnfs.py

@@ -98,13 +98,15 @@ class VeritasCNFSDriverTestCase(test.TestCase):
         volume = fake_volume.fake_volume_obj(self.context,
                                              provider_location=self._loc)
         snapshot = fake_volume.fake_volume_obj(self.context)
-        with mock.patch.object(drv, '_execute'):
+        with mock.patch('cinder.privsep.path.symlink'):
             m_exists.return_value = True
             drv._do_clone_volume(volume, volume.name, snapshot)
 
     @mock.patch.object(cnfs.VeritasCNFSDriver, '_get_local_volume_path')
     @mock.patch.object(os.path, 'exists')
-    def test_do_clone_volume_fail(self, m_exists, m_get_local_volume_path):
+    @mock.patch('cinder.privsep.path.symlink')
+    def test_do_clone_volume_fail(
+            self, m_symlink, m_exists, m_get_local_volume_path):
         """test _do_clone_volume() when filesnap over nfs is supported"""
         drv = self.driver
         volume = fake_volume.fake_volume_obj(self.context)

cinder/volume/drivers/veritas_cnfs.py

@@ -21,6 +21,7 @@ from oslo_utils import excutils
 from cinder import exception
 from cinder.i18n import _
 from cinder import interface
+import cinder.privsep.path
 from cinder.volume.drivers import nfs
 
 LOG = logging.getLogger(__name__)
@@ -155,7 +156,7 @@ class VeritasCNFSDriver(nfs.NfsDriver):
         tgt_vol_path = self._get_local_volume_path(cnfs_share, tgt_vol_name)
         src_vol_path = self._get_local_volume_path(cnfs_share, src_vol_name)
         tgt_vol_path_spl = tgt_vol_path + "::snap:vxfs:"
-        self._execute('ln', src_vol_path, tgt_vol_path_spl, run_as_root=True)
+        cinder.privsep.path.symlink(src_vol_path, tgt_vol_path_spl)
         LOG.debug("VeritasNFSDriver: do_clone_volume %(src_vol_path)s "
                   "%(tgt_vol_path)s %(tgt_vol_path_spl)s",
                   {'src_vol_path': src_vol_path,

etc/cinder/rootwrap.d/volume.filters

@@ -93,9 +93,6 @@ ionice_2: ChainingRegExpFilter, ionice, root, ionice, -c[0-3]
 # cinder/volume/utils.py: setup_blkio_cgroup()
 cgexec: ChainingRegExpFilter, cgexec, root, cgexec, -g, blkio:\S+
 
-# cinder/volume/driver.py
-ln: CommandFilter, ln, root
-
 # cinder/image/image_utils.py
 qemu-img: EnvFilter, env, root, LC_ALL=C, qemu-img
 qemu-img_convert: CommandFilter, qemu-img, root