Since last update: error in Nextcloud

[imc67]

Since the latest update there are errors with message:

Following symlinks is not allowed ('/app/data//core' -> '/app/code/core/' not inside '/app/data/') 

It's a rather clean setup without exotic apps.

[nebulon]

Where is this error shown? I can't reproduce this on any of our instances nor on a fresh installations.

[Kubernetes]

I also checked my NextCloud instance and didn't find any related message in the app logs.

[imc67]

In Nextcloud - Admin - Logging

I saw there is an option to view RAW log, here an example:

{
"reqId":"***redacted***",
"level":3,
"time":"2024-02-15T10:00:49+00:00",
"remoteAddr":"***redacted***",
"user":"***redacted***",
"app":"core",
"method":"GET",
"url":"/ocs/v2.php/apps/related_resources/related/talk?itemId=***redacted***&resourceType=&limit=0&format=json",
"message":"Following symlinks is not allowed ('/app/data//core' -> '/app/code/core/' not inside '/app/data/')",
"userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36",
"version":"28.0.2.5",
"data":{"app":"core"},
"id":"***redacted***"
}

and another one (I guessed it was Talk related due to the link in the error but it's not:

{
"reqId":"***redacted***",
"level":3,
"time":"2024-02-14T17:12:56+00:00",
"remoteAddr":"***redacted***",
"user":"***redacted***",
"app":"core",
"method":"GET",
"url":"/ocs/v2.php/apps/related_resources/related/files?itemId=***redacted***&format=json",
"message":"Following symlinks is not allowed ('/app/data//core' -> '/app/code/core/' not inside '/app/data/')",
"userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36",
"version":"28.0.2.5",
"data":{"app":"core"},
"id":"***redacted***"
}

[imc67]

Since 3 days the errors stopped while nothing has changed!

For now I set this topic to 'solved'.

[imc67]

The errors are back again and somehow because of the /app/data// symlink it might package related?

Remind that these errors are only visible in NextCloud Admin Settings then all the way down: Logs

[girish]

/app/code/core is not symlinked. However, the package creates a dummy symlink from /app/data/core to /app/code/core . The reason for this is that we move the plugins into a writable directory and the plugins do include "../.." to reach core files. This breaks if we don't create this dummy symlink. I wish nextcloud had a way to specify a separate plugin directory but it doesn't.

Which brings us to https://github.com/nextcloud/server/issues/1257 which is a report similar to this one. It seems one can set localstorage.allowSymlinks in the config file . This is not a security issue on Cloudron since the whole thing is sandboxed and symlinks cannot escape the filesystem.

@imc67 can you try adding that flag in your config ? https://github.com/nextcloud/server/blob/59f3c73c80b9c2f790de37a01821379e892b94ee/config/config.sample.php#L2029

[imc67]

@girish thanks for your research and suggestion! I just added the line with setting 'True'.

Let's wait a few days to see what happens, I'll keep you informed.

[girish]

@imc67 Just to double check, php should be like 'localstorage.allowsymlinks' => true, (and not 'True' which is python ).

[imc67]

@girish true

[imc67]

I can say that since the 'flag' was set, after 5 days there were no such errors anymore!

[girish]

@imc67 thanks, I have put that flag in the package as well now.