[Bug]: filesystem error with multi-byte character leads to crash on Ubuntu 22.04

[qgjdev]

⚠️ Before submitting, please verify the following: ⚠️

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

Bug description

The client crashes just a few seconds after start with following error (excerpt from syslog):

Aug 25 21:57:39 hostname com.nextcloud.desktopclient.nextcloud.desktop[382765]: terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
Aug 25 21:57:39 hostname com.nextcloud.desktopclient.nextcloud.desktop[382765]:   what():  filesystem error: Cannot convert character sequence: Ungültiges oder unvollständiges Multi-Byte- oder Wide-Zeichen
Aug 25 21:57:40 host systemd[5595]: app-gnome-com.nextcloud.desktopclient.nextcloud-382765.scope: Consumed 3.502s CPU time.

Steps to reproduce

3. Start Nextcloud Desktop
4. Wait a few seconds (I'm able to enter the settings window for a few seconds which says "418 KB to transfer" before having the client crashing)
5. Crash

Expected behavior

Be able to sync everything

Which files are affected by this bug

I'm unable to find out which file is affected by this issue

Operating system

Linux

Which version of the operating system you are running.

Pop!_OS 22.04 LTS, downloaded via ppa:nextcloud-devs/client

Package

Distro package manager

Nextcloud Server version

29.0.5.1

Nextcloud Desktop Client version

3.13.3

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

nextcloud.log doesn't print anything at all after starting the nextcloud client, which makes me think that there's no file transfers being triggered at all before client crash.

Additional info

I recently connected a second account to the client, which was shortly before the crash problems started.

EDIT: After deleting .config/Nextcloud and .local/share/Nextcloud folders, purging nextcloud-desktop and reinstalling, everything seems to be back working again. Still, I have no idea what caused the issue.

[adamcavendish]

Having the same issue with AppImage version of Nextcloud Linux client.

Nextcloud version 3.13.33.13 (build 25182)
Git revision e4e1bf9a4c1def61c444f086999d461e37851c9b
Using Qt 5.15.12, built against Qt 5.15.12
Using Qt platform plugin 'xcb'
Using 'OpenSSL 3.1.4 24 Oct 2023'
Running on Ubuntu 24.04 LTS, x86_64

[qgjdev]

Yeah I rechecked on AppImage and Flatpak version as well with the same result. It seems to be an issue with multiple accounts though, since after reinstalling everything and adding the second account, the issue came back. Then, when reinstalling again with only one account, the issue seemed to be gone.

[PedroBuffon]

On appimage i`m having the error too using Arch latest version:

qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""
terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Invalid or incomplete multibyte or wide character
[1]    8266 IOT instruction (core dumped)  ./nextcloud_desktop.appimage -l

I think it`s related to this too.

[rosa2]

Same problem in Ubuntu 22.04. I have several accounts.

[qgjdev]

Apparently this issue is not related to having multiple accounts. It pops up after every reboot, no matter if I'm using a single account or multiple. Very annoying, I need NC for everyday use and heavily rely on it's usage.

EDIT: I just removed some files through the website after which the desktop client crashed, so I suspect this might be related to client file deletion.

[qgjdev]

I just started nextcloud using nextcloud --logdebug with following output:

nextcloud.gui.application: Migrating old config from "/home/user/.local/share/Nextcloud" to "/home/user/.config/Nextcloud"
nextcloud.gui.application: Failed to move the old config directory to its new location ( "/home/user/.local/share/Nextcloud" to "/home/user/.config/Nextcloud" )
nextcloud.gui.application: Will move the individual files ("Private_sync.log")
nextcloud.gui.application: Fallback move of  "Private_sync.log" also failed
terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Ungültiges oder unvollständiges Multi-Byte- oder Wide-Zeichen
[1]    284354 IOT instruction (core dumped)  nextcloud --logdebug

No idea if this is in any way related to the crash, but maybe it helps.

EDIT: If this is related to incomplete multi-byte characters, it might help that my full name includes umlauts.

[rosa2]

Today I rebooted the computer and now it works. Ubuntu 22.04 Maybe was an update that needed reboot.

[benchti]

same here

Nextcloud-3.13.3-x86_64.AppImage / ubuntu

ben@ben-NUC:~/bin$ ./Nextcloud --logdebug
nextcloud.gui.application: Migrating old config from "/home/ben/.local/share/Nextcloud" to "/home/ben/.config/Nextcloud"
nextcloud.gui.application: Failed to move the old config directory to its new location ( "/home/ben/.local/share/Nextcloud" to "/home/ben/.config/Nextcloud" )
nextcloud.gui.application: Will move the individual files ("Nextcloud_sync.log", "NextcloudNursit_sync.log")
nextcloud.gui.application: Fallback move of  "Nextcloud_sync.log" also failed
nextcloud.gui.application: Fallback move of  "NextcloudNursit_sync.log" also failed
terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Chaîne multi-octets ou étendue de caractères invalide ou incomplète
Abandon (core dumped)

[taaz]

same here. Reboot didn't solve the problem.

I did a downgrade now back to version 3.4.2 and it works for now.

For me (using ubuntu mate with caja-integration [caja is the nautilus filemanager for mate]) it worked like that:

First I found out which nextcloud packages were recently upgraded: grep " upgrade " /var/log/dpkg.log Then I checked which versions are available: apt list -a nextcloud-desktop (that I did for all the upgraded packages nextcloud-desktop, libnextcloudsync0 and caja-nextcloud) Then I installed the older versions: sudo apt install nextcloud-desktop=3.4.2-1ubuntu1 libnextcloudsync0=3.4.2-1ubuntu1 caja-nextcloud=3.4.2-1ubuntu1

I hope that helps somebody for now.

[jas4711]

Hi. I have the same problem:

jas@kaka:~$ ~/bin/nextcloud --version
Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
Nextcloud version 3.13.33.13 (build 25182)
Git revision e4e1bf9a4c1def61c444f086999d461e37851c9b
Using Qt 5.15.12, built against Qt 5.15.12
Using Qt platform plugin 'xcb'
Using 'OpenSSL 3.1.4 24 Oct 2023'
Running on Trisquel GNU/Linux Aramo (11.0.1), x86_64
jas@kaka:~$ strace -e trace=access ~/bin/nextcloud 
...
access("/home/jas/moln/Dombloko/Dombloko HD5 AB/Leverant\303\266rsavtal/Sammanst\303\244llning avtal samt fakturor d\303\244r avtal saknas.  (1) (1).xlsx", F_OK) = 0
terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Invalid or incomplete multibyte or wide character
--- SIGABRT {si_signo=SIGABRT, si_code=SI_TKILL, si_pid=296924, si_uid=1000} ---
+++ killed by SIGABRT (core dumped) +++
Aborted (core dumped)

Server just upgraded to 29.0.5 when this started to occur, not certain it is related.

If I move the file away, it fixes this -- but the files are coming from the server with probably broken UTF-8 encoding - not sure if this is a problem on the client that uploaded the file or the server.

Downgrading the client to 3.12.7 makes it work - no crashes.

[zinzolin]

I have the same issue. The solution proposed by @taaz worked great for me. Thanks a lot!

Note: I am running Tuxedo OS (KDE and Ubuntu based).

I did a downgrade now back to version 3.4.2 and it works for now.

For me (using ubuntu mate with caja-integration [caja is the nautilus filemanager for mate]) it worked like that:

First I found out which nextcloud packages were recently upgraded: grep " upgrade " /var/log/dpkg.log Then I checked which versions are available: apt list -a nextcloud-desktop (that I did for all the upgraded packages nextcloud-desktop, libnextcloudsync0 and caja-nextcloud) Then I installed the older versions: sudo apt install nextcloud-desktop=3.4.2-1ubuntu1 libnextcloudsync0=3.4.2-1ubuntu1 caja-nextcloud=3.4.2-1ubuntu1

[taaz]

Glad that the downgrade helped some people.

But now I seem to have the problem that no new local files get synchronized to the server anymore. Unfortunately the "main dialog" is not suitable to check sync logs for a large amount of files (the owncloud client was a bit better in that) but it just seems that the new file doesn't get synced. The tray symbol changes for maybe 0.1s to the syncing symbol but then right away back and nothing gets synced. Also my nextcloud-caja filemanager integration adds no symbol to new local files:

Anyone with similar problems?

[jas4711]

I saw the same problem (i.e., no crash - but syncing just silently fails) when I downgraded to 3.4.2 but running the 3.12.7 appimage works for me. Version 3.13.33.13 just crash.

[taaz]

@jas4711 Thank you so much for that hint!

Unfortunately via apt I could only choose between 3.13.3 and 3.4.2. Now I downloaded the appimage for version 3.12.7 here (https://download.nextcloud.com/desktop/releases/Linux/) and suddenly the sync is working again.

I've spend already so much time testing around and now if finally works for now. Let's hope this issue will be fixed soon so we can again use up-to-date versions of the client.

[elabrosse]

Now I downloaded the appimage for version 3.12.7 here (https://download.nextcloud.com/desktop/releases/Linux/) and suddenly the sync is working again.

I encountered the same errors as OP with Nextcloud-3.13.3-x86_64.AppImage on Debian 12. From the logs I could pinpoint some file names that contained carriage return characters. cleaning up those file names mitigated the errors in the logs and allowed synchronization to proceed further.

The desktop client app would still silently crash at what looked like the very end of its synchronization process. The logs now did not contain any errors (no occurrence of "error" or "warning" keyword). The last log messages mentioned "[ info nextcloud.gui.folder /home/user/src/gui/folder.cpp:638 ]: Ignoring spurious notification for file [...]" which I ignored.

I followed this advice of rolling back the client version and I encounter no crash with Nextcloud-3.12.7-x86_64.AppImage. Will stick to 3.12 for the time being. Hope this helps anybody out there until the issue is resolved!

[pielonet]

I had the same problem today. Using AppImage as here (https://github.com/nextcloud/desktop/issues/7026#issuecomment-2320843804) saved my day

[criegerde]

Same for me having multiple accounts configured. I had to downgrade to Linux AppImage v. 3.13.2 and now it works like before. Ubuntu Server 22/24 Debian Client, Ubuntu Client

[molotov44]

We have around 150+ Linux Mint 21.3 clients, none of which are currently able to synchronize with our Nextcloud instance. Nextcloud-desktop logs show the following error:

Client latest 3.13.3, from PPA

nextcloud.gui.application: Fallback move of "Private_sync.log" also failed
terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Invalid or incomplete multi-byte or wide character
[1] 284354 IOT instruction (core dumped)  nextcloud --logdebug

Additional Information:

We hope there will be a quick hotfix. We had to quickly downgrade using:

sudo apt install nextcloud-desktop=3.4.2-1ubuntu1 libnextcloudsync0=3.4.2-1ubuntu1

[camilasan]

I was not able to reproduce this crash (multiple accounts on Arch Linux).

1. is the desktop client 3.13.3 always reliably crashing during sync? Is there anything else happening when it crashes?
2. are you syncing any kind of read-only folders?
3. do you all have special characters or spaces in the files/folders?

[julpec]

Same problem on Debian 12.6 + client 3.13.3 + server 29.0.5

terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Chaîne multi-octets ou étendue de caractères invalide ou incomplète

Downgrading to 3.7.3 solved the problem

[camilasan]

Also very important: what is the output of the command locale in your machines with the crash?

[bovender]

Another one over here... Crashes all the time -- used to work well, so something must have changed in my system that makes the Desktop client feel extremely uncomfortable.

Nextcloud-3.13.3-x86_64.appimage on Fedora 40 KDE

terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Invalid or incomplete multibyte or wide character

what is the output of the command locale in your machines with the crash?

$ locale
LANG=en_US.UTF-8
LC_CTYPE=en_US.UTF-8
LC_NUMERIC=de_DE.UTF-8
LC_TIME=en_GB.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=de_DE.UTF-8
LC_MESSAGES=en_US.UTF-8
LC_PAPER=de_DE.UTF-8
LC_NAME=de_DE.UTF-8
LC_ADDRESS=de_DE.UTF-8
LC_TELEPHONE=de_DE.UTF-8
LC_MEASUREMENT=de_DE.UTF-8
LC_IDENTIFICATION=de_DE.UTF-8
LC_ALL=

[julpec]

Also very important: what is the output of the command locale in your machines with the crash?

LANG=fr_FR.UTF-8
LANGUAGE=
LC_CTYPE="fr_FR.UTF-8"
LC_NUMERIC="fr_FR.UTF-8"
LC_TIME="fr_FR.UTF-8"
LC_COLLATE="fr_FR.UTF-8"
LC_MONETARY="fr_FR.UTF-8"
LC_MESSAGES="fr_FR.UTF-8"
LC_PAPER="fr_FR.UTF-8"
LC_NAME="fr_FR.UTF-8"
LC_ADDRESS="fr_FR.UTF-8"
LC_TELEPHONE="fr_FR.UTF-8"
LC_MEASUREMENT="fr_FR.UTF-8"
LC_IDENTIFICATION="fr_FR.UTF-8"
LC_ALL=

[jas4711]

I was not able to reproduce this crash (multiple accounts on Arch Linux).

1. is the desktop client 3.13.3 always reliably crashing during sync? Is there anything else happening when it crashes?

2. are you syncing any kind of read-only folders?

3. do you all have special characters or spaces in the files/folders?

The client crashes directly on startup when scanning folders and encountering a non-ascii filename. Multiple accounts has nothing to do with this, I only have one account. No read-only folders.

See my earlier post with example filename from 'strace':

https://github.com/nextcloud/desktop/issues/7026#issuecomment-2317348932

Removing that file makes the nextcloud application not crash anymore, but that is not really a solution for me since I want those files synchronized. Downgrading solves the problem.

For reference, I'm using Trisquel aramo (Ubuntu 22.04 clone) and locale output is below.

/Simon

LANG=sv_SE.UTF-8
LANGUAGE=
LC_CTYPE="sv_SE.UTF-8"
LC_NUMERIC="sv_SE.UTF-8"
LC_TIME="sv_SE.UTF-8"
LC_COLLATE="sv_SE.UTF-8"
LC_MONETARY="sv_SE.UTF-8"
LC_MESSAGES="sv_SE.UTF-8"
LC_PAPER="sv_SE.UTF-8"
LC_NAME="sv_SE.UTF-8"
LC_ADDRESS="sv_SE.UTF-8"
LC_TELEPHONE="sv_SE.UTF-8"
LC_MEASUREMENT="sv_SE.UTF-8"
LC_IDENTIFICATION="sv_SE.UTF-8"
LC_ALL=

[nwinkelstraeter]

I also have this problem with desktop client version 3.13.3 on ubuntu 22.04 and server version 29.0.5.

I managed to figure out a scenario where this crash reliably occurs.

Via the web interface i created the following file structure:

├── täst
│   ├── täst.md
│   └── test.md
└── test
    ├── täst.md
    └── test.md

These files were properly synced by the client without any issue. But if I rename or delete any of the files (via the web interface) where the filename or the complete path contains the 'ä' character, the client crashes on the next sync and also when restarting afterwards.

Deleting the corresponding file locally or restoring / renaming to original filename via web interface fixes the crash.

LANG=de_DE.UTF-8
LANGUAGE=de_DE:en
LC_CTYPE="de_DE.UTF-8"
LC_NUMERIC=de_DE.UTF-8
LC_TIME=de_DE.UTF-8
LC_COLLATE="de_DE.UTF-8"
LC_MONETARY=de_DE.UTF-8
LC_MESSAGES="de_DE.UTF-8"
LC_PAPER=de_DE.UTF-8
LC_NAME=de_DE.UTF-8
LC_ADDRESS=de_DE.UTF-8
LC_TELEPHONE=de_DE.UTF-8
LC_MEASUREMENT=de_DE.UTF-8
LC_IDENTIFICATION=de_DE.UTF-8
LC_ALL=

[bovender]

3.13.3 chokes on a new local file whose name contains an Umlaut ("Bilder für Quiz").

3.13.2 handles this file without problems.

When I renamed the file to replace the "ü" by an "ue" ("Bilder fuer Quiz"), 3.13.3 also handled it without problems.

However, interestingly, when I created a local file called "ü" (echo Umlaut > ü), 3.13.3 synced this file without problems. Likewise, a text file created via the web interface that was called "ä.md" did not cause a crash either. :confused:

The "Bilder für Quiz" file was created by someone else on an Apple device, and I had downloaded it from iCloud. Would that make a difference...? (How could that be, anyway?)

[julpec]

The "Bilder für Quiz" file was created by someone else on an Apple device, and I had downloaded it from iCloud. Would that make a difference...? (How could that be, anyway?)

Same for me : the problem occurred twice when another Windows user was working (without the client, via the web interface)

[afath-richard]

Issue

Like jas4711 https://github.com/nextcloud/desktop/issues/7026#issuecomment-2331231591 I encounter the same problem and same behavior:

1. is the desktop client 3.13.3 always reliably crashing during sync? Is there anything else happening when it crashes?

2. are you syncing any kind of read-only folders?

3. do you all have special characters or spaces in the files/folders?

The client crashes directly on startup when scanning folders and encountering a non-ascii filename. Multiple accounts has nothing to do with this, I only have one account. No read-only folders.

However, it happened only with this server, which is the one requiring a higher (than 3.4.2) client version :

Grade A

Running Nextcloud 28.0.6.1

NOT on latest patch level

Major version still supported

Scanned at 2024-07-09 13:09:51

But not this more recent one (which is still OK with client version 3.4.2) :

Grade A+

Running Nextcloud 29.0.4.1

Latest patch level

Major version still supported

Scanned at 2024-08-27 08:30:59

Provide your server version using https://scan.nextcloud.com/

Workaround

I'm using the appImage v.3.12.7 as a workaround but I'm not happy with it (lost integration with the filemanager, not using the APT repository / system libs).

My problem / Why it append?

I was initially using a 3.4.2 version installed from the debian stable APT repo. But I've been forced to use Nextcloud's dev PPA repository because one of my servers required a higher client version I couldn't get otherwise.

Extrapolation

I guess that my problem is the case for most people here who would have preferred to stick to the Debian client's stable version (at least with Debian base distros). Is it?

Suggestion

Could the 3.12.7 version make it's way quickly to the Debian / Mint stable repository? I would be surprised that a server stable version ships without updating the clients stable repositories to a compatible version too. But I imagine this is "because of" debian release policy. However, people here use different distros...

Couldn't there a solution in-between where Nextcloud would provide a stable PPA repository (in plus of the dev one) thanks to which professionals could upgrade before their stable package make it's way to the debian repo, without risking a (normal for a dev branch) breaking change? Does it exist already (where to find it)? Or maybe does Nextcloud depend on Debian (and other distros) to tell whether a package is stable or not...

My specs

My files do contain special chars.

$ cat /etc/lsb-release 
...
DISTRIB_DESCRIPTION="Linux Mint 21.3 Virginia"

$ cat /etc/upstream-release/lsb-release 
...
DISTRIB_RELEASE=22.04
...
DISTRIB_DESCRIPTION="Ubuntu Jammy Jellyfish"

$ locale
LANG=fr_FR.UTF-8
LANGUAGE=fr_FR
LC_CTYPE="fr_FR.UTF-8"
LC_NUMERIC="fr_FR.UTF-8"
LC_TIME="fr_FR.UTF-8"
LC_COLLATE="fr_FR.UTF-8"
LC_MONETARY="fr_FR.UTF-8"
LC_MESSAGES="fr_FR.UTF-8"
LC_PAPER="fr_FR.UTF-8"
LC_NAME="fr_FR.UTF-8"
LC_ADDRESS="fr_FR.UTF-8"
LC_TELEPHONE="fr_FR.UTF-8"
LC_MEASUREMENT="fr_FR.UTF-8"
LC_IDENTIFICATION="fr_FR.UTF-8"
LC_ALL=

Many thank to Nextcloud and their team for providing us with this great software, Thank you devs, maintainers and contributors.

[rosa2]

as i said, i had the problem and the error from the first post. then i rebooted and start working. then some times stoped working with the error reported by benchti in https://github.com/nextcloud/desktop/issues/7026#issuecomment-2317050114

nextcloud.gui.application: Migrating old config from "/home/user/.local/share/Nextcloud" to "/home/user/.config/Nextcloud"
nextcloud.gui.application: Failed to move the old config directory to its new location ( "/home/user/.local/share/Nextcloud" to "/home/user/.config/Nextcloud" )
nextcloud.gui.application: Will move the individual files ("Private_sync.log")
nextcloud.gui.application: Fallback move of  "Private_sync.log" also failed
terminate called after throwing an instance of 'std::filesystem::__cxx11::filesystem_error'
  what():  filesystem error: Cannot convert character sequence: Ungültiges oder unvollständiges Multi-Byte- oder Wide-Zeichen
[1]    284354 IOT instruction (core dumped)  nextcloud --logdebug

after deleting files in /home/user/.local/share/ it could copy after several times and started working again.

my locale

LANG=en_US.UTF-8
LANGUAGE=en_US:en
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=es_ES.UTF-8
LC_TIME=es_ES.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=es_ES.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=es_ES.UTF-8
LC_NAME=es_ES.UTF-8
LC_ADDRESS=es_ES.UTF-8
LC_TELEPHONE=es_ES.UTF-8
LC_MEASUREMENT=es_ES.UTF-8
LC_IDENTIFICATION=es_ES.UTF-8
LC_ALL=

Many thank to Nextcloud and their team for providing us with this great software, Thank you devs, maintainers and contributors.

as @afath-richard says

[rosa2]

i have another computer with Ubuntu 24.04 and it works ok. locale

LANG=en_US.UTF-8
LANGUAGE=
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=es_ES.UTF-8
LC_TIME=es_ES.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=es_ES.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=es_ES.UTF-8
LC_NAME=es_ES.UTF-8
LC_ADDRESS=es_ES.UTF-8
LC_TELEPHONE=es_ES.UTF-8
LC_MEASUREMENT=es_ES.UTF-8
LC_IDENTIFICATION=es_ES.UTF-8
LC_ALL=