Bug 419693

Application: ktorrent (5.1.0)

Qt Version: 5.9.5
Frameworks Version: 5.44.0
Operating System: Linux 4.15.0-91-generic x86_64
Distribution: Ubuntu 18.04.4 LTS

-- Information about the crash:
- What I was doing when the application crashed:

Steps to reproduce:
1. Download one or more torrents
2. When they are all finished dowloading, stop them from GUI
3. Select all torrents in the list, right click, remove (from list only)
==> Observations:
> If some torrents are left in the list (finished, stopped, or downloading) application does not crash.
> It does not matter if torrents you are removing are seeding, stopped or finished; if all are removed at once,
   application crashes.

The crash can be reproduced every time.

-- Backtrace:
Application: KTorrent (ktorrent), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f44501da600 (LWP 24445))]

Thread 7 (Thread 0x7f43edffb700 (LWP 27239)):
#0  0x00007f443e84b8af in pa_fdsem_after_poll () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-11.1.so
#1  0x00007f443e86335d in  () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-11.1.so
#2  0x00007f44425d2108 in pa_mainloop_dispatch () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#3  0x00007f44425d24de in pa_mainloop_iterate () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#4  0x00007f44425d2560 in pa_mainloop_run () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#5  0x00007f44425e03c9 in  () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#6  0x00007f443e873318 in  () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-11.1.so
#7  0x00007f4445c1a6db in start_thread (arg=0x7f43edffb700) at pthread_create.c:463
#8  0x00007f444a32588f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f43ca7fc700 (LWP 24479)):
#0  0x00007f4445c209f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5584f973a044) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4445c209f3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x5584f9739ff0, cond=0x5584f973a018) at pthread_cond_wait.c:502
#2  0x00007f4445c209f3 in __pthread_cond_wait (cond=0x5584f973a018, mutex=0x5584f9739ff0) at pthread_cond_wait.c:655
#3  0x00007f444afe15ab in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f444fa31413 in  () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#5  0x00007f444afe017d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4445c1a6db in start_thread (arg=0x7f43ca7fc700) at pthread_create.c:463
#7  0x00007f444a32588f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f43caffd700 (LWP 24478)):
#0  0x00007f444a2e89d0 in __GI___nanosleep (requested_time=0x7f43caffcd60, remaining=0x7f43caffcd60) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007f444b21721d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007f444fa2e668 in  () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#3  0x00007f444fa2ec09 in  () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#4  0x00007f444afe017d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f4445c1a6db in start_thread (arg=0x7f43caffd700) at pthread_create.c:463
#6  0x00007f444a32588f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f43cb7fe700 (LWP 24477)):
#0  0x00007f444a318bf9 in __GI___poll (fds=0x7f43b8118390, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f444fa318f8 in net::Poll::poll(int) () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#2  0x00007f444fa2e94a in  () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#3  0x00007f444fa2e9e6 in  () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#4  0x00007f444fa2ec09 in  () at /usr/lib/x86_64-linux-gnu/libKF5Torrent.so.6
#5  0x00007f444afe017d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4445c1a6db in start_thread (arg=0x7f43cb7fe700) at pthread_create.c:463
#7  0x00007f444a32588f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f442d611700 (LWP 24449)):
#0  0x00007f444a3140b4 in __GI___libc_read (fd=20, buf=0x7f442d610b90, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007f44441602b0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f444411b0b7 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f444411b570 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f444411b6dc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f444b2178ab in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f444b1bc90a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f444afdb23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f444afe017d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f4445c1a6db in start_thread (arg=0x7f442d611700) at pthread_create.c:463
#10 0x00007f444a32588f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f442f023700 (LWP 24447)):
#0  0x00007f444a318bf9 in __GI___poll (fds=0x7f44280284f0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f444411b5c9 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f444411b6dc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f444b2178ab in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f444b1bc90a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f444afdb23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f444c644d45 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#7  0x00007f444afe017d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f4445c1a6db in start_thread (arg=0x7f442f023700) at pthread_create.c:463
#9  0x00007f444a32588f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f44501da600 (LWP 24445)):
[KCrash Handler]
#6  0x00005584f78e95c1 in  ()
#7  0x00007f444c1ac0ac in QStyledItemDelegate::initStyleOption(QStyleOptionViewItem*, QModelIndex const&) const () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#8  0x00007f444c1aaf2c in QStyledItemDelegate::paint(QPainter*, QStyleOptionViewItem const&, QModelIndex const&) const () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#9  0x00007f444c1ed632 in QTreeView::drawRow(QPainter*, QStyleOptionViewItem const&, QModelIndex const&) const () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#10 0x00007f444c1f2b6d in QTreeView::drawTree(QPainter*, QRegion const&) const () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#11 0x00007f444c1f7615 in QTreeView::paintEvent(QPaintEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#12 0x00007f444bf7b048 in QWidget::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#13 0x00007f444c01c4de in QFrame::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#14 0x00007f444c18fb8b in QAbstractItemView::viewportEvent(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#15 0x00007f444c1f852c in QTreeView::viewportEvent(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#16 0x00007f444b1be5bc in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007f444bf3c815 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#18 0x00007f444bf44104 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#19 0x00007f444b1be8d8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00007f444bf7419a in QWidgetPrivate::sendPaintEvent(QRegion const&) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#21 0x00007f444bf7475a in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#22 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#23 0x00007f444bf75549 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#24 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#25 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#26 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#27 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#28 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#29 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#30 0x00007f444bf75549 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#31 0x00007f444bf75549 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#32 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#33 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#34 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#35 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#36 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#37 0x00007f444bf753c0 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#38 0x00007f444bf74366 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#39 0x00007f444bf4be64 in  () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#40 0x00007f444bf4c0a5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#41 0x00007f444bf6367f in QWidgetPrivate::syncBackingStore() () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#42 0x00007f444bf7b1b8 in QWidget::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#43 0x00007f444c08ec6b in QMainWindow::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#44 0x00007f444eb74b87 in KMainWindow::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libKF5XmlGui.so.5
#45 0x00007f444ebb99e5 in KXmlGuiWindow::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libKF5XmlGui.so.5
#46 0x00007f444bf3c83c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#47 0x00007f444bf44104 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#48 0x00007f444b1be8d8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#49 0x00007f444b1c104d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#50 0x00007f444b218263 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#51 0x00007f444411b417 in g_main_context_dispatch () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#52 0x00007f444411b650 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#53 0x00007f444411b6dc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#54 0x00007f444b21788f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#55 0x00007f444b1bc90a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#56 0x00007f444b1c59b4 in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#57 0x00005584f78b502a in  ()
#58 0x00007f444a225b97 in __libc_start_main (main=0x5584f78b2d60, argc=1, argv=0x7ffc4e328a58, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffc4e328a48) at ../csu/libc-start.c:310
#59 0x00005584f78b5a0a in _start ()

Reported using DrKonqi