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| -rw-r--r-- | tests/qemu-iotests/283 | 92 | ||||
| -rw-r--r-- | tests/qemu-iotests/283.out | 8 | ||||
| -rw-r--r-- | tests/qemu-iotests/group | 1 |
3 files changed, 101 insertions, 0 deletions
diff --git a/tests/qemu-iotests/283 b/tests/qemu-iotests/283 new file mode 100644 index 0000000000..293e557bd9 --- /dev/null +++ b/tests/qemu-iotests/283 @@ -0,0 +1,92 @@ +#!/usr/bin/env python +# +# Test for backup-top filter permission activation failure +# +# 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.verify_image_format(supported_fmts=['qcow2']) + +size = 1024 * 1024 + +""" Test description + +When performing a backup, all writes on the source subtree must go through the +backup-top filter so it can copy all data to the target before it is changed. +backup-top 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 +backup-top 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 │ + └─────────────┘ └───────┘ + +On activation (see .active field of backup-top state in block/backup-top.c), +backup-top is going 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'}) + +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() diff --git a/tests/qemu-iotests/283.out b/tests/qemu-iotests/283.out new file mode 100644 index 0000000000..daaf5828c1 --- /dev/null +++ b/tests/qemu-iotests/283.out @@ -0,0 +1,8 @@ +{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "target"}} +{"return": {}} +{"execute": "blockdev-add", "arguments": {"driver": "blkdebug", "image": {"driver": "null-co", "node-name": "base", "size": 1048576}, "node-name": "source"}} +{"return": {}} +{"execute": "blockdev-add", "arguments": {"driver": "blkdebug", "image": "base", "node-name": "other", "take-child-perms": ["write"]}} +{"return": {}} +{"execute": "blockdev-backup", "arguments": {"device": "source", "sync": "full", "target": "target"}} +{"error": {"class": "GenericError", "desc": "Cannot set permissions for backup-top filter: Conflicts with use by other as 'image', which uses 'write' on base"}} diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group index 9d30a4b6c4..1904223020 100644 --- a/tests/qemu-iotests/group +++ b/tests/qemu-iotests/group @@ -289,3 +289,4 @@ 279 rw backing quick 280 rw migration quick 281 rw quick +283 auto quick |