Bug 497069

Summary:	Using sftp, attempting to access a directory location in an unreachable remote causes Dolphin to freeze
Product:	[Applications] dolphin	Reporter:	Antti Savolainen <antti.savo>
Component:	general	Assignee:	Dolphin Bug Assignee <dolphin-bugs-null>
Status:	REPORTED ---
Severity:	crash	CC:	akselmo, john.kizer, kfm-devel, sdar
Priority:	NOR
Version First Reported In:	24.08.3
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Antti Savolainen 2024-12-05 07:08:19 UTC

SUMMARY
Demonstrative video: https://youtu.be/U5cpo9YrZkU
If I add a directory location to an sftp URL, dolphin freezes if the remote is not accessible.
If the connection re-enables during this freeze, dolphin seems to spam the remote with requests, which causes the remote to deny you access for a moment.

STEPS TO REPRODUCE
1. Add a unreachable sftp location to the location bar and add a directory location

OBSERVED RESULT
Dolphin freezes

EXPECTED RESULT
Dolphin should notify the user that the remote is unreachable

SOFTWARE/OS VERSIONS
Linux: Arch Linux 
KDE Plasma Version: 6.2.4
KDE Frameworks Version: 6.8.0
Qt Version: 6.8.0

Comment 1 John Kizer 2024-12-16 04:32:24 UTC

Hi - I can't reproduce this on my Fedora KDE 41 device using an internal sftp URL (for a machine that I took offline to test), and noticed in your demonstration video that you're attempting to connect to a URL outside of your own personal network.

Are you able to see if the same behavior happens on your system with an unreachable address on your local network? (Maybe something to do with how name resolution is working?)

Comment 2 Antti Savolainen 2024-12-16 12:23:43 UTC

Seems to be an issue with DNS resolved remotes. I managed to reproduce this with a location in my local network once but not a second time. I'll do more testing.

Comment 3 Antti Savolainen 2024-12-16 13:06:36 UTC

I think I pinpointed the issues. It's two simultaneous sftp connections. These can be to the same host even. In this video I use the location '10.0.0.3' and its domain name 'serveri.lan': https://youtu.be/HTNVX2vCKgE

1. Connect to both
2. Close Dolphin
3. Cut off the interface in the remote
4. Open Dolphin and try to reconnect to the remote

Comment 4 Akseli Lahtinen 2025-01-22 15:36:50 UTC

> 3. Cut off the interface in the remote

By this do you mean that if the sftp URL is unavailable, it freezes?

Comment 5 Antti Savolainen 2025-01-22 16:54:21 UTC

No no. I mean that I have a small server box on the floor. For the duration of step 3 I get up from my chair, onto the server and then run `sudo ip link set enp0s31f6 down`. Probably achievable by severing the connection with other methods, but this was what I did when creating the steps.