qmlscene crashed with SIGSEGV in UCAlarmModel::clear()

[Ricardo Salveti]

Using image 248 with mako, was able to make the clock-app to crash when removing an alarm from the alarm list.

To reproduce:
1 - Add 2 alarms;
2 - Remove them;
3 - Repeat until you're able to get a crash;

stacktrace:

Program terminated with signal SIGSEGV, Segmentation fault.
#0 0xb1081208 in UCAlarmModel::clear (this=this@entry=0x1309c58) at ucalarmmodel.cpp:148
148 ucalarmmodel.cpp: No such file or directory.
(gdb) bt full
#0 0xb1081208 in UCAlarmModel::clear (this=this@entry=0x1309c58) at ucalarmmodel.cpp:148
        alarm = 0x12768f8
        _container_ = {c = {{p = {static shared_null = {ref = {atomic = {_q_value = -1}}, alloc = 0, begin = 0, end = 0, array = {0x0}}, d = 0x133bdd8}, d = 0x133bdd8}}, brk = 0, i = {i = 0x133bdec}, e = {i = 0x133bdf0}}
#1 0xb1081314 in UCAlarmModel::refresh (this=0x1309c58) at ucalarmmodel.cpp:245
        alarms = {{p = {static shared_null = {ref = {atomic = {_q_value = -1}}, alloc = 0, begin = 0, end = 0, array = {0x0}}, d = 0xb2d57000}, d = 0xb2d57000}}
#2 0xb63671b2 in QObject::event (this=<optimized out>, e=<optimized out>) at kernel/qobject.cpp:1147
        mce = <optimized out>
        sw = {receiver = 0x1309c58, previousSender = 0x0, currentSender = {sender = 0xb10d083c <AlarmManager::instance()::instance>, signal = 3, ref = 1}, switched = true}
#3 0xb684c868 in QApplicationPrivate::notify_helper (this=this@entry=0x11def40, receiver=receiver@entry=0x1309c58, e=e@entry=0x1729548) at kernel/qapplication.cpp:3486
        consumed = <optimized out>
#4 0xb6850336 in QApplication::notify (this=0xbeb1a1cc, receiver=0x1309c58, e=0x1729548) at kernel/qapplication.cpp:3236
        w = 0x1309c58
        extra = <optimized out>
        isProxyWidget = <optimized out>
        __PRETTY_FUNCTION__ = "virtual bool QApplication::notify(QObject*, QEvent*)"
        res = <optimized out>
#5 0xb634b00a in QCoreApplication::notifyInternal (this=0xbeb1a1cc, receiver=receiver@entry=0x1309c58, event=event@entry=0x1729548) at kernel/qcoreapplication.cpp:881
        threadData = 0x11df028
        loopLevelCounter = {threadData = 0x11df028}
        result = false
        cbdata = {0x1309c58, 0x1729548, 0xbeb19f53}
        d = 0x1309cb8
#6 0xb634cc6c in sendEvent (event=0x1729548, receiver=0x1309c58) at kernel/qcoreapplication.h:232
No locals.
#7 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x11df028) at kernel/qcoreapplication.cpp:1485
        e = 0x1729548
        pe = <optimized out>
        r = 0x1309c58
        unlocker = {m = <synthetic pointer>}
        event_deleter = {d = 0x1729548}
        __PRETTY_FUNCTION__ = "static void QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*)"
        locker = {val = 18739268}
        startOffset = 0
        i = @0x11df03c: 5
        cleanup = {receiver = <optimized out>, event_type = 0, data = 0x11df028, exceptionCaught = true}
#8 0xb634d000 in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1343
        data = <optimized out>
#9 0xb637fe38 in postEventSourceDispatch (s=0x120de80) at kernel/qeventdispatcher_glib.cpp:279
        source = 0x120de80
#10 0xb5dcf39a in g_main_context_dispatch () from /lib/arm-linux-gnueabihf/libglib-2.0.so.0
No symbol table info available.
#11 0xb5dcf522 in ?? () from /lib/arm-linux-gnueabihf/libglib-2.0.so.0
No symbol table info available.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Alan Pope 🍺🐧🐱 🦄 (popey)]

Confirmed on 248 and 249.