Merge "Check configdrive size before writing to partition"

ironic_python_agent/errors.py

@@ -151,6 +151,17 @@ class ImageWriteError(RESTError):
         self.details = self.details.format(device, exit_code)
 
 
+class ConfigDriveTooLargeError(RESTError):
+    """Error raised when a configdrive is larger than the partition."""
+    message = 'Configdrive is too large for intended partition.'
+
+    def __init__(self, filename, filesize):
+        details = ('Configdrive at {0} has size {1}, which is larger than '
+                   'the intended partition.').format(filename, filesize)
+        super(ConfigDriveTooLargeError, self).__init__(details)
+        self.details = details
+
+
 class ConfigDriveWriteError(RESTError):
     """Error raised when a configdrive directory cannot be written to a
     device.

ironic_python_agent/extensions/standby.py

@@ -72,6 +72,11 @@ def _write_configdrive_to_partition(configdrive, device):
     filename = _configdrive_location()
     _write_configdrive_to_file(configdrive, filename)
 
+    # check configdrive size before writing it
+    filesize = os.stat(filename).st_size
+    if filesize > (64 * 1024 * 1024):
+        raise errors.ConfigDriveTooLargeError(filename, filesize)
+
     starttime = time.time()
     script = _path_to_script('shell/copy_configdrive_to_disk.sh')
     command = ['/bin/bash', script, filename, device]

ironic_python_agent/tests/extensions/standby.py

@@ -140,18 +140,20 @@ class TestStandbyExtension(test_base.BaseTestCase):
         gzip_read_mock.assert_called_once_with()
         write_mock.assert_called_once_with('ungzipped')
 
+    @mock.patch('os.stat', autospec=True)
     @mock.patch(('ironic_python_agent.extensions.standby.'
                  '_write_configdrive_to_file'),
                 autospec=True)
     @mock.patch(OPEN_FUNCTION_NAME, autospec=True)
     @mock.patch('ironic_python_agent.utils.execute', autospec=True)
     def test_write_configdrive_to_partition(self, execute_mock, open_mock,
-                                            configdrive_mock):
+                                            configdrive_mock, stat_mock):
         device = '/dev/sda'
         configdrive = standby._configdrive_location()
         script = standby._path_to_script('shell/copy_configdrive_to_disk.sh')
         command = ['/bin/bash', script, configdrive, device]
         execute_mock.return_value = 0
+        stat_mock.return_value.st_size = 5
 
         standby._write_configdrive_to_partition(configdrive, device)
         execute_mock.assert_called_once_with(*command)
@@ -166,6 +168,23 @@ class TestStandbyExtension(test_base.BaseTestCase):
 
         execute_mock.assert_called_once_with(*command)
 
+    @mock.patch('os.stat', autospec=True)
+    @mock.patch(('ironic_python_agent.extensions.standby.'
+                 '_write_configdrive_to_file'),
+                autospec=True)
+    @mock.patch(OPEN_FUNCTION_NAME, autospec=True)
+    @mock.patch('ironic_python_agent.utils.execute', autospec=True)
+    def test_write_configdrive_too_large(self, execute_mock, open_mock,
+                                         configdrive_mock, stat_mock):
+        device = '/dev/sda'
+        configdrive = standby._configdrive_location()
+        stat_mock.return_value.st_size = 65 * 1024 * 1024
+
+        self.assertRaises(errors.ConfigDriveTooLargeError,
+                          standby._write_configdrive_to_partition,
+                          configdrive,
+                          device)
+
     @mock.patch('hashlib.md5', autospec=True)
     @mock.patch(OPEN_FUNCTION_NAME, autospec=True)
     @mock.patch('requests.get', autospec=True)