On Sid (I'm not sure on Testing) K3b crashes in masterizing a CD/DVD if it's
choosen to verify::
================================================
k3b(23696) K3b::Device::DeviceHandler::run: finished command:
"(CommandDiskInfo|CommandToc|CommandCdText)"
k3b(23696) K3b::JobProgressDialog::slotNewSubTask: "Verifying track 1"
k3b(23696) K3b::ActivePipe::open: (K3b::ActivePipe) successfully opened pipe.
k3b(23696) K3b::ActivePipe::open: (K3b::ActivePipe) successfully opened pipe.
k3b(23696) K3b::MediaCache::blockDevice: "/dev/sr0"
k3b(23696) K3b::LsofWrapper::checkDevice: (K3b::LsofWrapper) matched: app:
"k3b"  pid:  23696
KCrash: Application 'k3b' crashing...
KCrash: Attempting to start /usr/lib/kde4/libexec/drkonqi from kdeinit
KCrash: Connect sock_file=/home/ombra/.kde/socket-lorenz/kdeinit4__0
QSocketNotifier: Invalid socket 11 and type 'Read', disabling...
Unable to start Dr. Konqi
Not forwarding the crash to Apport.
================================================

Hoping that this bug (if confermed) will be solved at least with the new
release of K3b-2.0.3

Happened to me both times I used it that day, on testing. Checksums of
individual files on the resulting DVD+R recordings matched the files.


One (probably only) of the report files:
k3b-20151109-234337.kcrash.txt

==================================================
Application: K3b (k3b), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f6c3700d800 (LWP 18280))]

Thread 3 (Thread 0x7f6c1851e700 (LWP 18287)):
#0 0x00007f6c2c7752d4 in g_ptr_array_set_size (array=0x1f25120,
length=length@entry=0) at
/build/glib2.0-VKSJTv/glib2.0-2.46.1/./glib/garray.c:1143
#1 0x00007f6c2c7a06c1 in g_main_context_prepare
(context=context@entry=0x7f6c100009a0,
priority=priority@entry=0x7f6c1851dc40) at
/build/glib2.0-VKSJTv/glib2.0-2.46.1/./glib/gmain.c:3413
#2 0x00007f6c2c7a110b in g_main_context_iterate
(context=context@entry=0x7f6c100009a0, block=block@entry=1,
dispatch=dispatch@entry=1, self=<optimized out>) at
/build/glib2.0-VKSJTv/glib2.0-2.46.1/./glib/gmain.c:3820
#3 0x00007f6c2c7a12ec in g_main_context_iteration
(context=0x7f6c100009a0, may_block=may_block@entry=1) at
/build/glib2.0-VKSJTv/glib2.0-2.46.1/./glib/gmain.c:3901
#4 0x00007f6c318ce406 in
QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)
(this=0x7f6c100008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:427
#5 0x00007f6c3189c331 in
QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)
(this=this@entry=0x7f6c1851dd80, flags=...) at kernel/qeventloop.cpp:149
#6 0x00007f6c3189c6a5 in
QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>)
(this=this@entry=0x7f6c1851dd80, flags=...) at kernel/qeventloop.cpp:204
#7 0x00007f6c3178b579 in QThread::exec() (this=this@entry=0x20a3c90) at
thread/qthread.cpp:538
#8 0x00007f6c3187c393 in QInotifyFileSystemWatcherEngine::run()
(this=0x20a3c90) at io/qfilesystemwatcher_inotify.cpp:265
#9 0x00007f6c3178de6c in QThreadPrivate::start(void*) (arg=0x20a3c90) at
thread/qthread_unix.cpp:352
#10 0x00007f6c2c02f0a4 in start_thread (arg=0x7f6c1851e700) at
pthread_create.c:309
#11 0x00007f6c303e406d in clone () at
../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 2 (Thread 0x7f6c070aa700 (LWP 18541)):
#0 0x00007f6c3178885b in QMutex::unlock() (newValue=0, expectedValue=1,
this=0x7f6bf8002ce0) at
../../include/QtCore/../../src/corelib/arch/qatomic_x86_64.h:145
#1 0x00007f6c3178885b in QMutex::unlock() (newValue=0, expectedValue=1,
this=0x7f6bf8002ce0) at
../../include/QtCore/../../src/corelib/arch/qatomic_x86_64.h:272
#2 0x00007f6c3178885b in QMutex::unlock() (this=<optimized out>) at
thread/qmutex.cpp:300
#3 0x00007f6c36ac7885 in K3b::Core::blockDevice(K3b::Device::Device*) ()
at /usr/lib/libk3blib.so.6
#4 0x00007f6c36b395ee in () at /usr/lib/libk3blib.so.6
#5 0x00007f6c36ad8775 in K3b::Thread::run() () at /usr/lib/libk3blib.so.6
#6 0x00007f6c3178de6c in QThreadPrivate::start(void*) (arg=0x25bfba0) at
thread/qthread_unix.cpp:352
#7 0x00007f6c2c02f0a4 in start_thread (arg=0x7f6c070aa700) at
pthread_create.c:309
#8 0x00007f6c303e406d in clone () at
../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 1 (Thread 0x7f6c3700d800 (LWP 18280)):
[KCrash Handler]
#6 0x00007f6c317d8073 in QString::mid(int, int) const (this=0x271eb38,
position=1, n=-1) at tools/qstring.cpp:3431
#7 0x000000000055d417 in _start ()
==================================================

The burning goes well and copies are correct.
The crash happens later, if and whwn you chose to verify