Bug 471467

SUMMARY

I have two cameras attached to my Ubuntu Mantic system:
045e:0772 Microsoft Corp. LifeCam Studio
05e3:f12a Genesys Logic, Inc. Digital Microscope
In the configuration dialogue I try to switch to camera 05e3:f12a. A crash occurs each time I try.

STEPS TO REPRODUCE
1.  Open configuration dialogue
2. Switch camera

OBSERVED RESULT

A crash occurs.

EXPECTED RESULT

no  crash

SOFTWARE/OS VERSIONS
Linux:  6.3.0-7-generic, Ubuntu Mantic
(available in About System)
KDE Plasma Version: 4:5.27.6.1-0ubuntu1
KDE Frameworks Version: 5.107.0
Qt Version: 5.15.9

ADDITIONAL INFORMATION

Downstream bug https://bugs.launchpad.net/ubuntu/+source/kamoso/+bug/2025060

Call hierarchy:

Thread 1 "kamoso" received signal SIGSEGV, Segmentation fault.
0x00007ffff57b66d3 in g_list_foreach (list=list@entry=0x3f800000 = {...}, func=0x7ffff590d640 <gst_context_unref.lto_priv.1.lto_priv>, user_data=user_data@entry=0x0)
    at ../../../glib/glist.c:1091
1091 GList *next = list->next;
(gdb) up
#1 0x00007ffff57bc53f in g_list_free_full (list=0x3f800000 = {...}, free_func=<optimized out>) at ../../../glib/glist.c:246
246 g_list_foreach (list, (GFunc) free_func, NULL);
(gdb)
#2 0x00007ffff591c70b in gst_element_dispose (object=0x555556317b50) at ../gst/gstelement.c:3434
3434 g_list_free_full (element->contexts, (GDestroyNotify) gst_context_unref);
(gdb)
#3 0x00007ffff6ee9da0 in g_object_unref (_object=0x555556317b50) at ../../../gobject/gobject.c:3891
3891 G_OBJECT_GET_CLASS (object)->dispose (object);
(gdb)
#4 0x00007ffff58ed343 in gst_object_unref (object=<optimized out>) at ../gst/gstobject.c:267
267 g_object_unref (object);
(gdb)
#5 0x00007ffff58f6858 in gst_bin_remove_func (bin=0x555556ca81f0, element=<optimized out>) at ../gst/gstbin.c:1817
1817 gst_object_unref (element);
(gdb)
#6 0x00007ffff58f1c56 in gst_bin_remove (bin=bin@entry=0x555556ca81f0, element=0x555556317b50) at ../gst/gstbin.c:1868
1868 result = bclass->remove_element (bin, element);
(gdb)
#7 0x00007ffff58f23b3 in gst_bin_dispose (object=0x555556ca81f0) at ../gst/gstbin.c:527
527 gst_bin_remove (bin, GST_ELEMENT_CAST (bin->children->data));
(gdb)
#8 0x00007ffff6ee9da0 in g_object_unref (_object=0x555556ca81f0) at ../../../gobject/gobject.c:3891
3891 G_OBJECT_GET_CLASS (object)->dispose (object);
(gdb)
#9 0x000055555556cd73 in WebcamControl::onBusMessage (message=<optimized out>, this=<optimized out>) at /usr/src/kamoso-23.04.2-0ubuntu1/src/video/webcamcontrol.cpp:306
306 stop();
(gdb)
#10 webcamWatch (message=<optimized out>, user_data=0x7fffffffd730) at /usr/src/kamoso-23.04.2-0ubuntu1/src/video/webcamcontrol.cpp:244
244 wc->onBusMessage(message);
(gdb)
#11 0x00007ffff590584f in gst_bus_source_dispatch (source=0x555556335b00, callback=0x55555556cc20 <webcamWatch(GstBus*, GstMessage*, gpointer)>, user_data=0x7fffffffd730)
    at ../gst/gstbus.c:821
821 keep = handler (bus, message, user_data);
(gdb)
#12 0x00007ffff57c032f in g_main_dispatch (context=0x7fffec000ee0) at ../../../glib/gmain.c:3460
3460 need_destroy = !(* dispatch) (source, callback, user_data);
(gdb)
#13 g_main_context_dispatch (context=0x7fffec000ee0) at ../../../glib/gmain.c:4200
4200 g_main_dispatch (context);
(gdb)
#14 0x00007ffff581b148 in g_main_context_iterate.constprop.0 (context=0x7fffec000ee0, block=<optimized out>, dispatch=1, self=<optimized out>) at ../../../glib/gmain.c:4276
4276 g_main_context_dispatch (context);
(gdb)
#15 0x00007ffff57bf170 in g_main_context_iteration (context=0x7fffec000ee0, may_block=1) at ../../../glib/gmain.c:4343
4343 retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
(gdb)

#16 0x00007ffff5d150ea in QEventDispatcherGlib::processEvents (this=0x555555669ed0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
423 bool result = g_main_context_iteration(d->mainContext, canWait);
(gdb)
#17 0x00007ffff5cb99db in QEventLoop::exec (this=this@entry=0x7fffffffd540, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:69
69 Q_DECL_CONSTEXPR inline operator uint() const noexcept { return uint(i); }
(gdb)
#18 0x00007ffff5cc1e2a in QCoreApplication::exec () at ../../include/QtCore/../../src/corelib/global/qflags.h:121
121 Q_DECL_CONSTEXPR inline QFlags(Enum flags) noexcept : i(Int(flags)) {}
(gdb)
#19 0x00007ffff6135df0 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1863
warning: Source file is more recent than executable.
1863 return QCoreApplication::exec();
(gdb)
#20 0x00007ffff696bf09 in QApplication::exec () at kernel/qapplication.cpp:2832
2832 return QGuiApplication::exec();
(gdb)
#21 0x0000555555567585 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/kamoso-23.04.2-0ubuntu1/src/main.cpp:47
47 return app.exec();
(gdb)
Initial frame selected; you cannot go up.
(gdb)