[Bug]: Cannot move shared folders to external storages without parent folder

[strangmann]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

When I try to move a directly shared directory (someone shared it with me) to an external storage, the web interface says that it is not possible to move the item. However, if I move the shared directory to a random folder outside the external storage, I can move the random folder to the external storage.

Steps to reproduce

1. Configure external Storage as user A
2. Generate as user A a direct share with user B
   3.1 Login as user B and try to move the folder to external storage (result of MOVE: error 403) -> error
   3.2 Login as user B, create a random directory and move the random folder to exterrnal storage -> success

Expected behavior

The folder should be moved without random folder, not via step 3.2 (by Steps to reproduce).
Otherwise the shared folder should not be moved to external storage.

Installation method

Community Manual installation with Archive

Nextcloud Server version

27

Operating system

RHEL/CentOS

PHP engine version

PHP 8.2

Web server

Nginx

Database engine version

MariaDB

Is this bug present after an update or on a fresh install?

None

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

Enabled:
  - activity: 2.19.0
  - admin_audit: 1.17.0
  - bookmarks: 13.1.3
  - bruteforcesettings: 2.7.0
  - calendar: 4.6.5
  - circles: 27.0.1
  - cloud_federation_api: 1.10.0
  - comments: 1.17.0
  - contacts: 5.5.2
  - contactsinteraction: 1.8.0
  - dashboard: 7.7.0
  - dav: 1.27.0
  - deck: 1.11.4
  - federatedfilesharing: 1.17.0
  - federation: 1.17.0
  - files: 1.22.0
  - files_external: 1.19.0
  - files_mindmap: 0.0.30
  - files_pdfviewer: 2.8.0
  - files_reminders: 1.0.0
  - files_rightclick: 1.6.0
  - files_sharing: 1.19.0
  - files_trashbin: 1.17.0
  - files_versions: 1.20.0
  - firstrunwizard: 2.16.0
  - forms: 3.4.6
  - integration_ews: 1.0.37
  - integration_openproject: 2.6.1
  - keeweb: 0.6.13
  - logreader: 2.12.0
  - lookup_server_connector: 1.15.0
  - nextcloud_announcements: 1.16.0
  - notifications: 2.15.0
  - notify_push: 0.6.9
  - oauth2: 1.15.2
  - onlyoffice: 8.2.4
  - password_policy: 1.17.0
  - photos: 2.3.0
  - privacy: 1.11.0
  - provisioning_api: 1.17.0
  - recommendations: 1.6.0
  - related_resources: 1.2.0
  - serverinfo: 1.17.0
  - settings: 1.9.0
  - sharebymail: 1.17.0
  - spreed: 17.1.6
  - support: 1.10.0
  - survey_client: 1.15.0
  - systemtags: 1.17.0
  - text: 3.8.0
  - theming: 2.2.0
  - theming_customcss: 1.15.0
  - twofactor_backupcodes: 1.16.0
  - updatenotification: 1.17.0
  - user_ldap: 1.17.0
  - user_status: 1.7.0
  - viewer: 2.1.0
  - weather_status: 1.7.0
  - workflow_script: 1.12.1
  - workflowengine: 2.9.0

Nextcloud Signing status

No response

Nextcloud Logs

... [16/Mar/2024:15:17:25 +0100] "MOVE /remote.php/dirToUser/testshare HTTP/2.0" 403 158 "-" ...

Additional info

No response

[strangmann]

Same error with NC 28

[strangmann]

Same error in 29.0.5

[strangmann]

Same issue in 29.0.7

[icewind1991]

Moving shared files (as the recipient) into external storage is supposed to be blocked. As it would lead to a situation where NC would show the file in the external storage that doesn't actually exist in the external storage.

The "workaround" here is a bug that should be fixed.

Nextcloud show however show a proper error message explaining why the share can't be moved instead of the current generic error.

[sorbaugh]

@strangmann looking through the issue, there are two things to do here:

1. Improve the error message
2. Properly block shares to be moved inside an external share even when they are in a folder

This would be the bugfix, however be informed that this would effectively change the current behavior.

[jfkorsmo]

Hi,

We experience this issue. We released this version: 29.0.7.1. And it took some time before our users reported dataloss (missing directories, corrupted parents/paths). We cannot roll back at this point, so we had to deactivate the functionality due to it causing dataloss.

We have no way of identifying which files has dissapaired either, any suggestions?

I cannot find any information about this bug here:
https://help.nextcloud.com/categories

For us, this is a critical bug. What is the status on it? How is the priority?