[Bug]: File sequence directory exists but is not writable in /lib/private/Snowflake/FileSequence.php:37 on Update to NC33

[greno2]

⚠️ 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 trying to update NC to 33.0.0 via updater.phar a issue arises with shared temp-directories on servers running multiple installations with different uid/gid as the directory /tmp/sfi_file_sequence/ (that already was created by a different installation) is not writable.

This seems to be related to the commit 65c9e34 as this is now checking for file permissions.

Manually setting a tempdirectory in config.php to eg $datadirectory/temp fixes the issue.

An unhandled exception has been thrown:
Exception: File sequence directory exists but is not writable in /home/REDACTED/lib/private/Snowflake/FileSequence.php:37
Stack trace:
#0 /home/REDACTED/lib/private/Snowflake/FileSequence.php(31): OC\Snowflake\FileSequence->ensureWorkdirExists()
#1 [internal function]: OC\Snowflake\FileSequence->__construct()
#2 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(74): ReflectionClass->newInstanceArgs()
#3 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->buildClass()
#4 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(157): OC\AppFramework\Utility\SimpleContainer->resolve()
#5 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#6 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(46): OC\ServerContainer->query()
#7 /home/REDACTED/lib/private/Server.php(1277): OC\AppFramework\Utility\SimpleContainer->get()
#8 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(186): OC\Server->OC\{closure}()
#9 /home/REDACTED/3rdparty/pimple/pimple/src/Pimple/Container.php(118): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#10 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(149): Pimple\Container->offsetGet()
#11 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#12 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(95): OC\ServerContainer->query()
#13 [internal function]: OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#14 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(82): array_map()
#15 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(74): OC\AppFramework\Utility\SimpleContainer->buildClassConstructorParameters()
#16 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->buildClass()
#17 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(157): OC\AppFramework\Utility\SimpleContainer->resolve()
#18 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#19 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(46): OC\ServerContainer->query()
#20 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(208): OC\AppFramework\Utility\SimpleContainer->get()
#21 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(186): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#22 /home/REDACTED/3rdparty/pimple/pimple/src/Pimple/Container.php(118): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#23 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(149): Pimple\Container->offsetGet()
#24 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#25 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(95): OC\ServerContainer->query()
#26 [internal function]: OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#27 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(82): array_map()
#28 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(74): OC\AppFramework\Utility\SimpleContainer->buildClassConstructorParameters()
#29 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->buildClass()
#30 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(157): OC\AppFramework\Utility\SimpleContainer->resolve()
#31 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#32 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(46): OC\ServerContainer->query()
#33 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(208): OC\AppFramework\Utility\SimpleContainer->get()
#34 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(186): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#35 /home/REDACTED/3rdparty/pimple/pimple/src/Pimple/Container.php(118): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#36 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(149): Pimple\Container->offsetGet()
#37 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#38 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(95): OC\ServerContainer->query()
#39 [internal function]: OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#40 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(82): array_map()
#41 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(74): OC\AppFramework\Utility\SimpleContainer->buildClassConstructorParameters()
#42 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(131): OC\AppFramework\Utility\SimpleContainer->buildClass()
#43 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(157): OC\AppFramework\Utility\SimpleContainer->resolve()
#44 /home/REDACTED/lib/private/ServerContainer.php(155): OC\AppFramework\Utility\SimpleContainer->query()
#45 /home/REDACTED/lib/private/AppFramework/Utility/SimpleContainer.php(46): OC\ServerContainer->query()
#46 /home/REDACTED/lib/public/Server.php(37): OC\AppFramework\Utility\SimpleContainer->get()
#47 /home/REDACTED/core/register_command.php(142): OCP\Server::get()
#48 /home/REDACTED/lib/private/Console/Application.php(83): require_once('...')
#49 /home/REDACTED/console.php(86): OC\Console\Application->loadCommands()
#50 /home/REDACTED/occ(33): require_once('...')
#51 {main}

Steps to reproduce

Try to update existing installation of NC <33 on a server with shared temp-Directory (and unset tempdirectory in config.php) via updater.phar

Expected behavior

Use unique tempnam instead of fixed directory name or private temp-directory within datadirectory as default

Nextcloud Server version

33

Operating system

RHEL/CentOS

PHP engine version

PHP 8.3

Web server

Apache (supported)

Database engine version

MariaDB

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

Upgraded to a MAJOR version (ex. 31 to 32)

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

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "REDACTED"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "32.0.6.1",
        "overwrite.cli.url": "https:\/\/REDACTED",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "maintenance": true,
        "loglevel": 2
    }
}

List of activated Apps

Enabled:
  - activity: 5.0.0
  - app_api: 32.0.0
  - bruteforcesettings: 5.0.0
  - calendar: 6.2.0
  - circles: 32.0.0
  - cloud_federation_api: 1.16.0
  - comments: 1.22.0
  - contacts: 8.3.2
  - contactsinteraction: 1.13.1
  - dashboard: 7.12.0
  - dav: 1.34.2
  - federatedfilesharing: 1.22.0
  - federation: 1.22.0
  - files: 2.4.0
  - files_downloadlimit: 5.0.0-dev.0
  - files_pdfviewer: 5.0.0
  - files_reminders: 1.5.0
  - files_sharing: 1.24.1
  - files_trashbin: 1.22.0
  - files_versions: 1.25.0
  - firstrunwizard: 5.0.0
  - logreader: 5.0.0
  - lookup_server_connector: 1.20.0
  - mail: 5.7.0
  - nextcloud_announcements: 4.0.0
  - notes: 4.13.0
  - notifications: 5.0.0
  - oauth2: 1.20.0
  - password_policy: 4.0.0
  - photos: 5.0.0
  - privacy: 4.0.0
  - profile: 1.1.0
  - provisioning_api: 1.22.0
  - recommendations: 5.0.0
  - related_resources: 3.0.0
  - serverinfo: 4.0.0
  - settings: 1.15.1
  - sharebymail: 1.22.0
  - support: 4.0.0
  - survey_client: 4.0.0
  - suspicious_login: 10.0.0
  - systemtags: 1.22.0
  - text: 6.0.1
  - theming: 2.7.0
  - twofactor_backupcodes: 1.21.0
  - twofactor_totp: 14.0.0
  - updatenotification: 1.22.0
  - user_status: 1.12.0
  - viewer: 5.0.0
  - weather_status: 1.12.0
  - webhook_listeners: 1.3.0
  - workflowengine: 2.14.0
Disabled:
  - admin_audit: 1.23.0
  - deck: 1.16.3 (installed 1.16.3)
  - encryption: 2.21.0
  - files_external: 1.25.1
  - forms: 5.2.4 (installed 5.2.4)
  - tasks: 0.17.1 (installed 0.17.1)
  - twofactor_nextcloud_notification: 7.0.0
  - user_ldap: 1.24.0

Nextcloud Signing status

Nextcloud Logs

Additional info

No response

[Riariseriam]

Hi, same problem here, but I don't quite get your description.

My value in config.php is:
'datadirectory' => '.../nextcloud/data',

How exactly do I need to change it?

1. Do I need to add it like this:
   'datadirectory' => '.../nextcloud/data/temp',

2. Or replace it like this:
   'datadirectory' => '.../nextcloud/temp',

3. Or add a new line like this:
   'datadirectory' => '.../nextcloud/data',
   'datadirectory' => '.../nextcloud/temp',

4. Or add this:
   'tempdirectory' => '/tmp/nextcloudtemp',

I tried all of them and still had the same issue...I updated my other instance just fine, but this one is trouble :(
I can't run any basic occ commands anymore although I am sure I do have the writing rights...

My temp-directories are not shared per se since it has Folders for each user ergo each instance...(I am not sure with this though)

[neufeind]

Use "tempdirectory" (your option 4). This can for example be placed in the data-dir.

The problem appeared with v33 since it's the first version to ship "Snowflake IDs" (#56045).

[internethering]

I've this problem too: lib/private/Snowflake/FileSequence.php shouldn't have a hardcoded public const LOCK_FILE_DIRECTORY = 'sfi_file_sequence'; - If you've two Nextcloud instances on one server, then this cause problems.

[TimoKramer]

how do i quickfix this?

[greno2]

how do i quickfix this?

create a unique directory "somewhere" for each NC-Installation and set config/config.php tempdirectory to this path.

[susnux]

cc @artonge @Altahrim

[lx4r]

Use "tempdirectory" (your option 4). This can for example be placed in the data-dir.

The problem appeared with v33 since it's the first version to ship "Snowflake IDs" (#56045).

Thanks, that worked for me. Can I revert the change to config.php after the update and delete the tmp folder, which I created inside the data dir in my case?

Thanks in advance for the help :)

[kaffeeundsalz]

To add to the discussion, I can confirm that the issue is not limited to the original context (updating Nextcloud via updater.phar). It also reliably breaks when running occ maintenance:repair and possibly whenever FileSequence.php is involved while the lock directory created relative to sys_get_temp_dir() is not writeable.

I also find the resulting exception quite misleading. "File sequence directory exists but is not writable" suggests a problem with the Nextcloud data directory (appdata_*), permissions, or ownership – but those are unrelated because the actual failure is the inability to create/use sys_get_temp_dir()/sfi_file_sequence. As @greno2 suggested, explicitly configuring a writeable temp directory in config.php resolves the issue.

The assumption that sys_get_temp_dir() is writable and suitable for instance-level locking does not hold in shared hosting environments (which broke the procedure in my case), multi-instance systems and restricted/containerized setups. At minimum, the error message should include the fully resolved path it attempted to use (e.g. /tmp/sfi_file_sequence) to avoid sending users down the wrong debugging path.