Thread 1 (Thread 0x7ab7f4f14280 (LWP 176938)):
[KCrash Handler]
#6  __pthread_kill_implementation (no_tid=0, signo=6, threadid=134930507055744) at ./nptl/pthread_kill.c:44
#7  __pthread_kill_internal (signo=6, threadid=134930507055744) at ./nptl/pthread_kill.c:78
#8  __GI___pthread_kill (threadid=134930507055744, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#9  0x00007ab7f8e42476 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#10 0x00007ab7f8e287f3 in __GI_abort () at ./stdlib/abort.c:79
#11 0x00007ab7f96fdb6e in qAbort () at ./src/corelib/global/qglobal.cpp:161
#12 0x00007ab7f96f820a in qt_message_fatal<QString&> (message=..., context=...) at ./src/corelib/global/qlogging.cpp:2025
#13 qt_message(QtMsgType, const QMessageLogContext &, const char *, typedef __va_list_tag __va_list_tag *) (msgType=msgType@entry=QtFatalMsg, context=..., msg=<optimized out>, ap=ap@entry=0x7ffde408add0) at ./src/corelib/global/qlogging.cpp:374
#14 0x00007ab7f96fe511 in QMessageLogger::fatal (this=<optimized out>, msg=<optimized out>) at ./src/corelib/global/qlogging.cpp:889
#15 0x00007ab7f96c2ac2 in qt_assert (assertion=assertion@entry=0x7ab7f9a4c85c "info.isAbsolute()", file=file@entry=0x7ab7f9a4c72e "./thumbnail/thumbnail.cpp", line=line@entry=170) at ./src/corelib/global/qassert.cpp:68
#16 0x00007ab7f9a406d4 in ThumbnailProtocol::get (this=0x7ffde408b910, url=...) at ./thumbnail/thumbnail.cpp:170
#17 0x00007ab7f9914765 in KIO::WorkerSlaveBaseBridge::get (this=0x621f5f39e160, url=...) at ./src/core/workerbase_p.h:71
#18 0x00007ab7f991052e in KIO::SlaveBase::dispatch (this=0x621f5f39e160, command=67, data=...) at ./src/core/slavebase.cpp:1168
#19 0x00007ab7f99c12ba in KIO::SlaveBase::dispatchLoop() [clone .constprop.0] (this=<optimized out>) at ./src/core/slavebase.cpp:350
#20 0x00007ab7f990eefd in KIO::WorkerBase::dispatchLoop (this=this@entry=0x7ffde408b910) at ./src/core/workerbase.cpp:27
#21 0x00007ab7f9a44a3c in kdemain (argc=<optimized out>, argc@entry=4, argv=0x7ffde408c4b8) at ./thumbnail/thumbnail.cpp:114
#22 0x0000621f5e1d95a0 in main (argc=5, argv=0x7ffde408c638) at /usr/include/x86_64-linux-gnu/qt6/QtCore/qvarlengtharray.h:84

thumbnail.cpp:170 is this:

> Q_ASSERT(info.isAbsolute())

> I saw it crash when using the file picker/saver. I'm not sure if it's related.

It's very much related. Can you tell which program you used specifically?

A possibly relevant merge request was started @ https://invent.kde.org/frameworks/kio/-/merge_requests/1673

A possibly relevant merge request was started @ https://invent.kde.org/network/kio-extras/-/merge_requests/363

Git commit 7be69649a6d3ba8786ff6586aa0769fc05d0ac9c by Nicolas Fella.
Committed on 13/08/2024 at 18:21.
Pushed by nicolasfella into branch 'master'.

[thumbnail] Print file name when asserting

This gives us more information to debug the issue

M  +1    -1    thumbnail/thumbnail.cpp

https://invent.kde.org/network/kio-extras/-/commit/7be69649a6d3ba8786ff6586aa0769fc05d0ac9c

Git commit 9052690e66052f32c021256439e81168d501a0d7 by Nicolas Fella.
Committed on 14/08/2024 at 12:34.
Pushed by nicolasfella into branch 'release/24.08'.

[thumbnail] Print file name when asserting

This gives us more information to debug the issue
(cherry picked from commit 7be69649a6d3ba8786ff6586aa0769fc05d0ac9c)

M  +1    -1    thumbnail/thumbnail.cpp

https://invent.kde.org/network/kio-extras/-/commit/9052690e66052f32c021256439e81168d501a0d7

I used the Signal Desktop Messenger (Flatpak) for this and can reproduce a crash on an up-to-date system when trying to save a file from a chat. Opening/selecting files on the system doesn't seem to cause an issue.

Created attachment 172912 [details]
second KCrash report

It still crashes with the 24.08.0 update

A possibly relevant merge request was started @ https://invent.kde.org/frameworks/kio/-/merge_requests/1703

Two questions:
 - does the crash happen in any folder, only in specific ones (like one starting with smb://)
 - Can share the list of you enabled thumbnailer (in dolphin > preview), as a screenshot for instance

Git commit d09989f93698a01aef719bfd19bd665269df091e by Nicolas Fella.
Committed on 07/11/2024 at 14:16.
Pushed by nicolasfella into branch 'master'.

[previewjob] Assert that path is absolute

The worker expects that, so catch failure early

M  +4    -0    src/gui/previewjob.cpp

https://invent.kde.org/frameworks/kio/-/commit/d09989f93698a01aef719bfd19bd665269df091e

From https://crash-reports.kde.org/organizations/kde/issues/107873

0   libc.so.6                       0x7f073d29eb1c      [inlined] __pthread_kill_implementation (pthread_kill.c:44)
1   libc.so.6                       0x7f073d29eb1c      [inlined] __pthread_kill_internal (pthread_kill.c:78)
2   libc.so.6                       0x7f073d29eb1c      pthread_kill (pthread_kill.c:89)
3   libc.so.6                       0x7f073d29eb1b      [inlined] __pthread_kill_implementation (pthread_kill.c:43)
4   libc.so.6                       0x7f073d29eb1b      [inlined] __pthread_kill_internal (pthread_kill.c:78)
5   libc.so.6                       0x7f073d29eb1b      [inlined] pthread_kill (pthread_kill.c:89)
6   libc.so.6                       0x7f073d29eb1b      [inlined] __pthread_kill_implementation (pthread_kill.c:43)
7   libc.so.6                       0x7f073d29eb1b      [inlined] __pthread_kill_internal (pthread_kill.c:78)
8   libc.so.6                       0x7f073d29eb1b      pthread_kill (pthread_kill.c:89)
9   libc.so.6                       0x7f073d24526d      __GI_raise (raise.c:26)
10  libc.so.6                       0x7f073d2288fe      abort (abort.c:79)
11  libQt6Core.so.6.8.1             0x7f073df0e0bd      [inlined] qAbort (qassert.cpp:49)
12  libQt6Core.so.6.8.1             0x7f073df0e0bd      [inlined] qt_message_fatal<T> (qlogging.cpp:2116)
13  libQt6Core.so.6.8.1             0x7f073df0e0bd      qt_message (qlogging.cpp:382)
14  libQt6Core.so.6.8.1             0x7f073df0ef9a      QMessageLogger::fatal (qlogging.cpp:884)
15  libQt6Core.so.6.8.1             0x7f073df0f06c      qt_assert_x (qassert.cpp:114)
16  libKF6KIOGui.so.6.9.0           0x7f07405564cb      KIO::PreviewJobPrivate::createThumbnail (previewjob.cpp:835)
17  libKF6KIOGui.so.6.9.0           0x7f074057541a      KIO::PreviewJobPrivate::getOrCreateThumbnail (previewjob.cpp:710)
18  libKF6KIOGui.so.6.9.0           0x7f0740576017      KIO::PreviewJob::slotResult (previewjob.cpp:592)
19  libQt6Core.so.6.8.1             0x7f073de7ada8      [inlined] ? (qobjectdefs_impl.h:486)
20  libQt6Core.so.6.8.1             0x7f073de7ada8      doActivate<T> (qobject.cpp:4124)
21  libKF6CoreAddons.so.6.9.0       0x7f073f2d0475      KJob::result (moc_kjob.cpp:622)
22  libKF6CoreAddons.so.6.9.0       0x7f073f2d2b6a      KJob::finishJob (kjob.cpp:115)
23  libQt6Core.so.6.8.1             0x7f073de7ada8      [inlined] ? (qobjectdefs_impl.h:486)
24  libQt6Core.so.6.8.1             0x7f073de7ada8      doActivate<T> (qobject.cpp:4124)
25  libKF6KIOCore.so.6.9.0          0x7f073f575534      [inlined] KIO::WorkerInterface::finished (moc_workerinterface_p.cpp:515)
26  libKF6KIOCore.so.6.9.0          0x7f073f575534      KIO::WorkerInterface::dispatch (workerinterface.cpp:127)
27  libKF6KIOCore.so.6.9.0          0x7f073f573cb6      KIO::WorkerInterface::dispatch (workerinterface.cpp:58)
28  libKF6KIOCore.so.6.9.0          0x7f073f57086d      KIO::Worker::gotInput (worker.cpp:260)
29  libQt6Core.so.6.8.1             0x7f073de7ada8      [inlined] ? (qobjectdefs_impl.h:486)
30  libQt6Core.so.6.8.1             0x7f073de7ada8      doActivate<T> (qobject.cpp:4124)
31  libQt6Core.so.6.8.1             0x7f073de108fc      QObject::event (qobject.cpp:1419)
32  libQt6Widgets.so.6.8.1          0x7f073effff47      QApplicationPrivate::notify_helper (qapplication.cpp:3296)
33  libQt6Core.so.6.8.1             0x7f073deb5717      QCoreApplication::notifyInternal2 (qcoreapplication.cpp:1168)
34  libQt6Core.so.6.8.1             0x7f073deb8241      QCoreApplicationPrivate::sendPostedEvents (qcoreapplication.cpp:1968)
35  libQt6Core.so.6.8.1             0x7f073dc725ce      postEventSourceDispatch (qeventdispatcher_glib.cpp:246)
36  libglib-2.0.so.0.8000.0         0x7f073b4155b5      <unknown>
37  libglib-2.0.so.0.8000.0         0x7f073b474717      <unknown>
38  libglib-2.0.so.0.8000.0         0x7f073b414a53      g_main_context_iteration
39  libQt6Core.so.6.8.1             0x7f073dc702ce      QEventDispatcherGlib::processEvents (qeventdispatcher_glib.cpp:399)
40  libQt6Core.so.6.8.1             0x7f073dec1aea      QEventLoop::exec (qeventloop.cpp:194)
41  libQt6Widgets.so.6.8.1          0x7f073ee1793a      QDialog::exec (qdialog.cpp:567)
42  xdg-desktop-portal-kde          0x643107951846      FileChooserPortal::OpenFile (filechooser.cpp:488)
43  xdg-desktop-portal-kde          0x6431078ac368      FileChooserPortal::qt_static_metacall (moc_filechooser.cpp:188)
44  xdg-desktop-portal-kde          0x6431078ae979      FileChooserPortal::qt_metacall (moc_filechooser.cpp:235)
45  libQt6DBus.so.6.8.1             0x7f073e99a49b      QDBusConnectionPrivate::deliverCall (qdbusintegrator.cpp:1008)
46  libQt6DBus.so.6.8.1             0x7f073e99b202      QDBusConnectionPrivate::activateCall (qdbusintegrator.cpp:910)
47  libQt6DBus.so.6.8.1             0x7f073e99dd6a      QDBusConnectionPrivate::activateObject (qdbusintegrator.cpp:1485)
48  libQt6DBus.so.6.8.1             0x7f073e99e6e9      QDBusActivateObjectEvent::placeMetaCall (qdbusintegrator.cpp:1605)
49  libQt6Core.so.6.8.1             0x7f073de108fc      QObject::event (qobject.cpp:1419)
50  libQt6Widgets.so.6.8.1          0x7f073effff47      QApplicationPrivate::notify_helper (qapplication.cpp:3296)
51  libQt6Core.so.6.8.1             0x7f073deb5717      QCoreApplication::notifyInternal2 (qcoreapplication.cpp:1168)
52  libQt6Core.so.6.8.1             0x7f073deb8241      QCoreApplicationPrivate::sendPostedEvents (qcoreapplication.cpp:1968)
53  libQt6Core.so.6.8.1             0x7f073dc725ce      postEventSourceDispatch (qeventdispatcher_glib.cpp:246)
54  libglib-2.0.so.0.8000.0         0x7f073b4155b5      <unknown>
55  libglib-2.0.so.0.8000.0         0x7f073b474717      <unknown>
56  libglib-2.0.so.0.8000.0         0x7f073b414a53      g_main_context_iteration
57  libQt6Core.so.6.8.1             0x7f073dc702ce      QEventDispatcherGlib::processEvents (qeventdispatcher_glib.cpp:399)
58  libQt6Core.so.6.8.1             0x7f073dec1aea      QEventLoop::exec (qeventloop.cpp:194)
59  libQt6Core.so.6.8.1             0x7f073deb8c2c      QCoreApplication::exec (qcoreapplication.cpp:1513)
60  xdg-desktop-portal-kde          0x6431078aa322      main (xdg-desktop-portal-kde.cpp:50)
61  libc.so.6                       0x7f073d22a1c9      __libc_start_call_main (libc_start_call_main.h:58)
62  libc.so.6                       0x7f073d22a28a      __libc_start_main_alias_1 (libc-start.c:360)
63  xdg-desktop-portal-kde          0x6431078aa684      _start


Somehow item.localPath() is "."

*** Bug 491896 has been marked as a duplicate of this bug. ***

A possibly relevant merge request was started @ https://invent.kde.org/frameworks/kio/-/merge_requests/1770

A possibly relevant merge request was started @ https://invent.kde.org/network/kdeconnect-kde/-/merge_requests/764

Git commit b2e67aacb4d1d958b710d903d7c2f0987f8c32ff by Nicolas Fella.
Committed on 23/12/2024 at 00:46.
Pushed by nicolasfella into branch 'master'.

[kio] Handle error when getting mount point

The DBus reply is implicitly converted to QString, so when the call fails we get the call error message as string

We then write that into UDS_LOCAL_PATH, which causes issues later on

SENTRY: DOLPHIN-5CT

M  +7    -1    kio/kiokdeconnect.cpp

https://invent.kde.org/network/kdeconnect-kde/-/commit/b2e67aacb4d1d958b710d903d7c2f0987f8c32ff

Git commit be86637a4f71693b29288e93f7f3bedde95ac4a7 by Nicolas Fella.
Committed on 23/12/2024 at 00:52.
Pushed by nicolasfella into branch 'release/24.12'.

[kio] Handle error when getting mount point

The DBus reply is implicitly converted to QString, so when the call fails we get the call error message as string

We then write that into UDS_LOCAL_PATH, which causes issues later on

SENTRY: DOLPHIN-5CT
(cherry picked from commit b2e67aacb4d1d958b710d903d7c2f0987f8c32ff)

M  +7    -1    kio/kiokdeconnect.cpp

https://invent.kde.org/network/kdeconnect-kde/-/commit/be86637a4f71693b29288e93f7f3bedde95ac4a7

> Somehow item.localPath() is "."

d'oh, my assert was slightly wrong, it's printing the file's folder path, excluding the file name.

The actual full path is something like "./someFile"

It can be reproduced by entering "file:." into the file dialog's address bar

A possibly relevant merge request was started @ https://invent.kde.org/frameworks/kio/-/merge_requests/1772

A possibly relevant merge request was started @ https://invent.kde.org/network/kio-extras/-/merge_requests/394

Git commit 07c68404decf95ad0897685a1c5071bfbf0254b5 by Nicolas Fella.
Committed on 10/01/2025 at 18:04.
Pushed by nicolasfella into branch 'master'.

[thumbnail] Fix assert message

Print the full file path, not just the folder path

M  +1    -1    thumbnail/thumbnail.cpp

https://invent.kde.org/network/kio-extras/-/commit/07c68404decf95ad0897685a1c5071bfbf0254b5

Git commit 0ba7ab4e6941785d63ffd8d6c68a5853763454f5 by Nicolas Fella.
Committed on 10/01/2025 at 18:57.
Pushed by nicolasfella into branch 'release/24.12'.

[thumbnail] Fix assert message

Print the full file path, not just the folder path
(cherry picked from commit 07c68404decf95ad0897685a1c5071bfbf0254b5)

M  +1    -1    thumbnail/thumbnail.cpp

https://invent.kde.org/network/kio-extras/-/commit/0ba7ab4e6941785d63ffd8d6c68a5853763454f5

failing assertion for signal-desktop snap apparently https://crash-reports.kde.org/organizations/kde/issues/112252/events/e599410f6ce348559db6ef8b1eaa8ecf/?project=36

(can't test as snap is being a bit broken for me ^^)

*** Bug 501172 has been marked as a duplicate of this bug. ***

For me this crash behavior started after 2025-01-29, judging from my list of downloaded files.
Saving files from signal-desktop (installed from snap) worked fine until then.

I'm seeing this bug in Signal too, I'm using the Signal-desktop Flatpak.

As Laura said, I think this started happening around the end of January. Downloading files worked fine before that.

I am seeing this error in journalctl:
---
xdg-desktop-portal-kde: ASSERT failure in PreviewJobPrivate::getOrCreateThumbnail: "Local path for url file:./.cache is not absolute: ./.cache", file ./src/gui/previewjob.cpp, line 716
---
I'm on KDE Neon, relevant installed packages:
kf6-kio: 6.11.0+p24.04+vstable+git20250303.0733-0
xdg-desktop-portal-kde: 6.3.2+p24.04+vstable+git20250225.1925-0

*** Bug 501599 has been marked as a duplicate of this bug. ***

The sentry issue has 34 events.
Changing back to confirmed since the prior work was merged

*** Bug 504255 has been marked as a duplicate of this bug. ***

Okay I can reproduce this with ASHPD application which is used to test portals https://flathub.org/apps/com.belmoussaoui.ashpd.demo

1. Open ASHPD
2. Select File Chooser
3. Go to save file section
4. Type ".cache" to current folder
5. Press request
6. File dialog opens in ~/.cache
7. And then crashes immediately due to the previewjob not getting an absolute path

I think the solution is to make sure whatever passes the ".cache" to the file dialog etc to turn it into absolute URL before starting the file dialog.

Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.80
KDE Frameworks Version: 6.16.0
Qt Version: 6.9.0
Kernel Version: 6.15.0-61.fc43.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 3600 6-Core Processor
Memory: 16 GiB of RAM (15.5 GiB usable)
Graphics Processor: AMD Radeon RX 6600

To clarify it doesnt need to be ".cache", it can also be "Pictures" to cause the crash. But if its "~/Pictures" it works.

Thanks, we can easily work around not absolute paths in the portal as those dont make sense cross process. KFileWidget docs also say no relative paths but doesnt check it and runs into the assert sometimes

#include <KFileWidget>
#include <QApplication>
#include <QUrl>
#include <unistd.h>

int main(int argc, char**argv){
    chdir(getenv("HOME"));
    QApplication app(argc, argv);
    KFileWidget f(QUrl("file:.cache")); // does not explode, ignores URL
    // KFileWidget f(QUrl("file:./.cache")); // explodes
    f.setUrl(QUrl("file:.cache")); // explodes
    f.show();
    app.exec();
}

Actually it does not say say so

 /*!
     * Sets the directory to view.
     *
     * \a url URL to show.
     *
     * \a clearforward Indicates whether the forward queue
     * should be cleared.
     */
    void setUrl(const QUrl &url, bool clearforward = true);


    /*!
     * Sets the URL to preselect to \a url
     *
     * This method handles absolute URLs (remember to use fromLocalFile for local paths).
     * It also handles relative URLs, which you should construct like this:
     * QUrl relativeUrl; relativeUrl.setPath(fileName);
     *
     * \since 5.33
     */
    void setSelectedUrl(const QUrl &url);

We can make the same happen via QFileDialog -> plasma-integtration-> KFileWidget

#include <QApplication>
#include <QUrl>
#include <unistd.h>
#include <QFileDialog>

int main(int argc, char**argv){
    chdir(getenv("HOME"));
    QApplication app(argc, argv);
    QFileDialog f;
    f.setDirectoryUrl(QUrl("file:.cache"));
    f.show();
    app.exec();
}

A possibly relevant merge request was started @ https://invent.kde.org/plasma/xdg-desktop-portal-kde/-/merge_requests/401

Git commit 7c8e601a663eb33029e2723bbd2372c89e0cb9be by David Redondo.
Committed on 10/06/2025 at 12:01.
Pushed by davidre into branch 'master'.

filechooser: Ignore non absolute current_folder urls

These do not make sense in cross process communication
SENTRY:XDG-DESKTOP-PORTAL-KDE-G4

M  +8    -0    src/filechooser.cpp

https://invent.kde.org/plasma/xdg-desktop-portal-kde/-/commit/7c8e601a663eb33029e2723bbd2372c89e0cb9be

A possibly relevant merge request was started @ https://invent.kde.org/plasma/xdg-desktop-portal-kde/-/merge_requests/402

Git commit 609752566234575f68c38cd24fbccb4c6e8b133f by David Redondo.
Committed on 10/06/2025 at 13:07.
Pushed by davidre into branch 'Plasma/6.4'.

filechooser: Ignore non absolute current_folder urls

These do not make sense in cross process communication
SENTRY:XDG-DESKTOP-PORTAL-KDE-G4


(cherry picked from commit 7c8e601a663eb33029e2723bbd2372c89e0cb9be)

Co-authored-by: David Redondo <kde@david-redondo.de>

M  +8    -0    src/filechooser.cpp

https://invent.kde.org/plasma/xdg-desktop-portal-kde/-/commit/609752566234575f68c38cd24fbccb4c6e8b133f

A possibly relevant merge request was started @ https://invent.kde.org/frameworks/kio/-/merge_requests/1910

Git commit 6552bc6f280b2eddff4b1da931004a8a9230ac81 by David Redondo.
Committed on 11/06/2025 at 07:53.
Pushed by davidre into branch 'master'.

kfilewidget: Resolve relative file urls against current working dir

We need to work with absolute urls for previewjob which asserts
on relative urls.

M  +11   -6    src/filewidgets/kfilewidget.cpp

https://invent.kde.org/frameworks/kio/-/commit/6552bc6f280b2eddff4b1da931004a8a9230ac81