[Bug]: Useless error notifications while sync is stuck: server responded with an error while reading directory

[ph00lt0]

⚠️ Before submitting, please verify the following: ⚠️

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

Bug description

Nextcloud creates very unhelpful errors.

This list continues for ever since the latest update of the desktop client. No option to find any reason for it. When looking in the settings window it shows some on a metadata folder that has not been modified since 2015: operation cancelled.

Removing this folder had no effect on the stream of errors nextcloud is creating.

Steps to reproduce

1. try to use nextcloud

Expected behavior

A normal working product without data loss and constant sync errors.

Which files are affected by this bug

unclear

Operating system

Mac OS

Which version of the operating system you are running.

13.0 (22A380)

Package

Appimage

Nextcloud Server version

25.0.2

Nextcloud Desktop Client version

3.6.6

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

Updated from a minor version (ex. 3.4.2 to 3.4.4)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

Are you using an external user-backend?

• Default internal user-backend
• LDAP/ Active Directory
• SSO - SAML
• Other

Nextcloud Server logs

no relevant logs

Additional info

No response

[ph00lt0]

Re-initiated sync folder connection results in this vague error:

Impossible to find the problem. Once again, nextcloud fucked something up in the update of the desktop client. Honestly this is so frustrating. Test your shit!

[ph00lt0]

Same issue reported by this user: https://help.nextcloud.com/t/server-responded-with-error-when-reading-directory-operation-aborted/139572/2

[ph00lt0]

This seems to be a server bug. Server also cashed:
"Internal Server Error

The server encountered an internal error and was unable to complete your request.
Please contact the server administrator if this error reappears multiple times, please include the technical details below in your report.
More details can be found in the server log."

[szaimen]

Nextcloud creates very unhelpful errors.

I think this is rather a desktop bug.

[sveken]

Also seeing the same problem,
It has currently gone away after visiting the web panel for myself however other users are running into this.

[ph00lt0]

@szaimen could be but i reinstalled the desktop client 3 versions back from the mentioned above and keeps spitting the same errors. Windows clients seem unaffected. Unfortunately nextcloud's logging is very poor and I cannot seem to find any explanation

[ph00lt0]

But also if the desktop app manages to crash the entire server because of this, this may be a good way to exploit the server. I see a denial of service here.

[szaimen]

For security issues see https://hackerone.com/nextcloud

[ph00lt0]

I do not have a POC, just may be a good start for a test @szaimen. I see not point in reporting this here.

After some further digging I am pretty confident that the above errors are caused by a hardcoded chunk size in the desktop client. The chunks used are rather large and do not seem to being adjusted automatically, which I would recommend as fix. Network limitations should be taken into account when using this. When I manually overwrite the chunksize of your app it runs without problems.

[szaimen]

After some further digging I am pretty confident that the above errors are caused by a hardcoded chunk size in the desktop client.

okay, then it looks like the issue is located correctly in the desktop repo.

[PaulDebus]

I can reproduce this error on Fedora Linux running version 3.7.4 of the Nextcloud client installed from RPM, the server is running Nextcloud 25.0.3
A second connection to a server with Nextcloud 24.0.10 Enterprise works well.

The error has existed for a couple of days now

I would be happy to help debug, just let me know if you need more information

[garphil]

Hi, any update on this ?
I tried to unsync/resync folder, no effect. Seems to happen more on directory who are in sync with multiple clients, not with those in sync with only one client, but I may be wrong.

[ph00lt0]

i am unsubscribing from this thread as I stopped nextcloud because of continuous issues like this one.

[Extarys]

Been getting a lot of "Operation cancelled: directory not found" while syncing from one computer to another.

I saw a GH issue back from 2021, closed due to inactivity. Nobody seem to care for the usability of Nextcloud :/

[melroy89]

Same issue today with NC30! aggh!

[Extarys]

I had to disconnect the client, remove the directory on the local machine and add the account again for it to sync properly.

[melroy89]

I created a new issue for the latest 3.14.0 desktop client release. See pr referenced above.

It's giving the same very vague error messages. But clearly it's not a server issue, they should change the error messages.

I also created a new issue, because is could this time pin point the exact version of where it went wrong and which versions still worked. Since this ticket is about client version 3.6.6.