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diff --git a/tests/qemu-iotests/283 b/tests/qemu-iotests/283
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+#!/usr/bin/env python3
+# group: auto quick
+#
+# Test for copy-before-write filter permission conflict
+#
+# Copyright (c) 2019 Virtuozzo International GmbH.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+import iotests
+
+# The test is unrelated to formats, restrict it to qcow2 to avoid extra runs
+iotests.script_initialize(
+    supported_fmts=['qcow2'],
+)
+
+size = 1024 * 1024
+
+""" Test description
+
+When performing a backup, all writes on the source subtree must go through the
+copy-before-write filter so it can copy all data to the target before it is
+changed.  copy-before-write filter is appended above source node, to achieve
+this thing, so all parents of source node are handled. A configuration with
+side parents of source sub-tree with write permission is unsupported (we'd have
+append several copy-before-write filter like nodes to handle such parents). The
+test create an example of such configuration and checks that a backup is then
+not allowed (blockdev-backup command should fail).
+
+The configuration:
+
+    ┌────────┐  target  ┌─────────────┐
+    │ target │ ◀─────── │ backup_top  │
+    └────────┘          └─────────────┘
+                            │
+                            │ backing
+                            ▼
+                        ┌─────────────┐
+                        │   source    │
+                        └─────────────┘
+                            │
+                            │ file
+                            ▼
+                        ┌─────────────┐  write perm   ┌───────┐
+                        │    base     │ ◀──────────── │ other │
+                        └─────────────┘               └───────┘
+
+copy-before-write filter wants to unshare write permission on its source child.
+Write unsharing will be propagated to the "source->base" link and will conflict
+with other node write permission. So permission update will fail and backup job
+will not be started.
+
+Note, that the only thing which prevents backup of running on such
+configuration is default permission propagation scheme. It may be altered by
+different block drivers, so backup will run in invalid configuration. But
+something is better than nothing. Also, before the previous commit (commit
+preceding this test creation), starting backup on such configuration led to
+crash, so current "something" is a lot better, and this test actual goal is
+to check that crash is fixed :)
+"""
+
+vm = iotests.VM()
+vm.launch()
+
+vm.qmp_log('blockdev-add', **{
+    'node-name': 'target',
+    'driver': 'null-co',
+    'size': size,
+})
+
+vm.qmp_log('blockdev-add', **{
+    'node-name': 'source',
+    'driver': 'blkdebug',
+    'image': {'node-name': 'base', 'driver': 'null-co', 'size': size}
+})
+
+vm.qmp_log('blockdev-add', **{
+    'node-name': 'other',
+    'driver': 'blkdebug',
+    'image': 'base',
+    'take-child-perms': ['write']
+})
+
+vm.qmp_log('blockdev-backup', sync='full', device='source', target='target')
+
+vm.shutdown()
+
+
+print('\n=== copy-before-write filter should be gone after job-finalize ===\n')
+
+# Check that the copy-before-write node is gone after job-finalize.
+
+vm = iotests.VM()
+vm.launch()
+
+vm.qmp_log('blockdev-add', **{
+    'node-name': 'source',
+    'driver': 'null-co',
+})
+
+vm.qmp_log('blockdev-add', **{
+    'node-name': 'target',
+    'driver': 'null-co',
+})
+
+vm.qmp_log('blockdev-backup',
+           job_id='backup',
+           device='source',
+           target='target',
+           sync='full',
+           filter_node_name='backup-filter',
+           auto_finalize=False,
+           auto_dismiss=False)
+
+vm.event_wait('BLOCK_JOB_PENDING', 5.0)
+
+# The copy-before-write filter should still be present prior to finalization
+assert vm.node_info('backup-filter') is not None
+
+vm.qmp_log('job-finalize', id='backup')
+vm.event_wait('BLOCK_JOB_COMPLETED', 5.0)
+
+# The filter should be gone now.  Check that by trying to access it
+# with qemu-io (which will most likely crash qemu if it is still
+# there.).
+vm.qmp_log('human-monitor-command',
+           command_line='qemu-io backup-filter "write 0 1M"')
+
+# (Also, do an explicit check.)
+assert vm.node_info('backup-filter') is None
+
+vm.qmp_log('job-dismiss', id='backup')
+vm.event_wait('JOB_STATUS_CHANGE', 5.0, {'data': {'status': 'null'}})
+
+vm.shutdown()