Bug#926062: qbitorrent crashes, blames QNetworkAccessM

[bruno zanetti]

I tried to reproduce the segmentation fault on Buster / qbittorrent 4.1.5
with a few torrents and a hundred trackers added but to no avail.
It makes me think that it is triggered by a singular combination of cpu
speed and/or network speed and/or number of torrent/trackers and/or
whatever else.

@Shirish: have you tried qbittorrent in bullseye or sid? Did you get the
same crash?

As I see in https://github.com/qbittorrent/qBittorrent/issues/9667, the
problem might be related to Qt 5.11, so maybe it's gone in the current
stable or newer version.

Regards

BZ

Bug#926062: qbitorrent crashes, blames QNetworkAccessM

[sledgehammer999]

This seems the same bug as
https://github.com/qbittorrent/qBittorrent/issues/9667
A possible workaround is in PR:
https://github.com/qbittorrent/qBittorrent/pull/10445

Or you can just disable the download of tracker favicons from the advanced
settings.
Out of curiosity: How many trackers do you have? (number is shown in the
sidepanel)

On Sat, Apr 6, 2019 at 2:12 AM Tobias Frost  wrote:

> Control: serverity -1 important
> Control: tags -1 unreproducible moreinfo
>
> Hi shirish,
>
> I tried to reproduce your SEGV, but here qbittorrent seems to work
> fine. Do you have additional informations about how to trigger the
> SEGV, like what you are doing to trigger it or like?
>
> Cheers from the Salzburg BSP,
> tobi
>
>

Bug#926062: qbitorrent crashes, blames QNetworkAccessM

[Tobias Frost]

Control: serverity -1 important
Control: tags -1 unreproducible moreinfo

Hi shirish,

I tried to reproduce your SEGV, but here qbittorrent seems to work
fine. Do you have additional informations about how to trigger the
SEGV, like what you are doing to trigger it or like?

Cheers from the Salzburg BSP,
tobi 

Bug#926062: qbitorrent crashes, blames QNetworkAccessM

[shirish शिरीष]

Package: qbittorrent
Version: 4.1.5-1
Severity: serious

Dear Maintainer,

Sharing below the debugging session -

$ gdb qbittorrent
GNU gdb (Debian 8.2.1-2) 8.2.1
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
.
Find the GDB manual and other documentation resources online at:
.

--Type  for more, q to quit, c to continue without paging--
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from qbittorrent...Reading symbols from
/usr/lib/debug/.build-id/ad/0f65ab90b9bf916a54c3e15e7050a91eda4ba3.debug...done.
done.
(gdb) run
Starting program: /usr/bin/qbittorrent
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 558,
resource id: 10513977, major code: 40 (TranslateCoords), minor code: 0

Thread 17 "QNetworkAccessM" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffc997f700 (LWP 26557)]
0x76bf8ba4 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Network.so.5
(gdb) bt
#0  0x76bf8ba4 in  () at /usr/lib/x86_64-linux-gnu/libQt5Network.so.5
#1  0x76bf7c69 in  () at /usr/lib/x86_64-linux-gnu/libQt5Network.so.5
#2  0x768bd182 in QObject::event(QEvent*)
(this=0x7fffac06f100, e=) at kernel/qobject.cpp:1251
#3  0x774884b1 in QApplicationPrivate::notify_helper(QObject*,
QEvent*) (this=this@entry=
0x55db9840, receiver=receiver@entry=0x7fffac06f100,
e=e@entry=0x7fff94003aa0) at kernel/qapplication.cpp:3726
#4  0x7748f950 in QApplication::notify(QObject*, QEvent*)
(this=0x55db9780, receiver=0x7fffac06f100, e=0x7fff94003aa0)
at kernel/qapplication.cpp:3485
#5  0x5568ac42 in Application::notify(QObject*, QEvent*)
(this=, receiver=0x7fffac06f100, event=) at ../../src/app/application.cpp:622
#6  0x768935a9 in QCoreApplication::notifyInternal2(QObject*, QEvent*)
(receiver=0x7fffac06f100, event=0x7fff94003aa0)
at 
../../include/QtCore/5.11.3/QtCore/private/../../../../../src/corelib/thread/qthread_p.h:307
#7  0x7689659b in QCoreApplication::sendEvent(QObject*, QEvent*)
--Type  for more, q to quit, c to continue without paging--
(event=0x7fff94003aa0, receiver=)
at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:234
#8  0x7689659b in
QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*)
(receiver=0x0, event_type=0, data=0x568718a0) at
kernel/qcoreapplication.cpp:1744
#9  0x768e5233 in postEventSourceDispatch(GSource*,
GSourceFunc, gpointer) (s=0x7fffac003f10)
at kernel/qeventdispatcher_glib.cpp:276
#10 0x75558f2e in g_main_dispatch (context=0x7fffac000bf0) at
../../../glib/gmain.c:3182
#11 0x75558f2e in g_main_context_dispatch
(context=context@entry=0x7fffac000bf0) at ../../../glib/gmain.c:3847
#12 0x755591c8 in g_main_context_iterate
(context=context@entry=0x7fffac000bf0, block=block@entry=1,
dispatch=dispatch@entry=1, self=)
at ../../../glib/gmain.c:3920
#13 0x7555925c in g_main_context_iteration
(context=0x7fffac000bf0, may_block=may_block@entry=1)
at ../../../glib/gmain.c:3981
--Type  for more, q to quit, c to continue without paging--
#14 0x768e4863 in
QEventDispatcherGlib::processEvents(QFlags)
(this=0x7fffac000b20, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#15 0x7689227b in
QEventLoop::exec(QFlags)
(this=this@entry=0x7fffc997ed60, flags=..., flags@entry=...)
at ../../include/QtCore/../../src/corelib/global/qflags.h:140
#16 0x766e1ec6 in QThread::exec() (this=)
at ../../include/QtCore/../../src/corelib/global/qflags.h:120
#17 0x766ebaa7 in QThreadPrivate::start(void*)
(arg=0x568716b0) at thread/qthread_unix.cpp:367
#18 0x7660ffa3 in start_thread (arg=) at
pthread_create.c:486
#19 0x7621d82f in clone () at
../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb) quit
A debugging session is active.

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable-debug'), (500,
'testing-debug'), (500, 'unstable'), (1, 'experimental-debug'), (1,
'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 4.19.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_IN, LC_CTYPE=en_IN (charmap=UTF-8), LANGUAGE=en_IN:en
(charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: