Version:            (using KDE 4.2.98)
OS:                Linux
Installed from:    Ubuntu Packages

A user at https://launchpad.net/bugs/407446 reported a crash upon opening the KDM module in System Settings.

Backtrace is as follows:

#0  QDataStream::operator>> (this=0x0, i=@0xbfff0bfc)
    at io/qdatastream.cpp:661
No locals.
#1  0x007b49fd in KServiceFactory (this=0x909fd88)
    at ../../kdecore/services/kservicefactory.cpp:44
	str = (class QDataStream *) 0x0
	i = <value optimized out>
#2  0x007b4d4c in KServiceFactory::self ()
    at ../../kdecore/sycoca/ksycocafactory.h:200
No locals.
#3  0x007aa1bf in KService::serviceByMenuId (_name=@0xbfff0d2c)
    at ../../kdecore/services/kservice.cpp:600
No locals.
#4  0x007afff2 in KService::serviceByStorageId (_storageId=@0xbfff0d2c)
    at ../../kdecore/services/kservice.cpp:605
	service = {d = 0xbfff0d2c}
	tmp = {static null = {<No data fields>}, static shared_null = {ref = {
      _q_value = 2819}, alloc = 0, size = 0, data = 0xcad45a, clean = 0, 
    simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, 
    reserved = 0, array = {0}}, static shared_empty = {ref = {_q_value = 63}, 
    alloc = 0, size = 0, data = 0xcad46e, clean = 0, simpletext = 0, 
    righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {
      0}}, d = 0x6a5248, static codecForCStrings = 0x0}
#5  0x001aaa1f in locateModule (module=@0xbfff0e48)
    at ../../kcmshell/main.cpp:73
	path = {static null = {<No data fields>}, static shared_null = {
    ref = {_q_value = 2819}, alloc = 0, size = 0, data = 0xcad45a, clean = 0, 
    simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, 
    reserved = 0, array = {0}}, static shared_empty = {ref = {_q_value = 63}, 
    alloc = 0, size = 0, data = 0xcad46e, clean = 0, simpletext = 0, 
    righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {
      0}}, d = 0x90445d8, static codecForCStrings = 0x0}
	service = {d = 0x8ff3da0}
	__PRETTY_FUNCTION__ = "KSharedPtr<KService> locateModule(const QByteArray&)"
#6  0x001acb85 in kdemain (_argc=4, _argv=0xbfff1034)
    at ../../kcmshell/main.cpp:224
	service = {d = 0xd696910}
	i = 0
	aboutData = {d = 0x8ff2e88}
	app = {<KApplication> = {<QApplication> = {<QCoreApplication> = {<QObject> = {_vptr.QObject = 0x1afe48, static staticMetaObject = {d = {
              superdata = 0x0, stringdata = 0xc54cc0 "QObject", 
              data = 0xc54d60, extradata = 0xca81b8}}, d_ptr = 0x9006468, 
          static staticQtMetaObject = {d = {superdata = 0x0, 
              stringdata = 0xc5e4a0 "Qt", data = 0xc61380, 
              extradata = 0x0}}}, static staticMetaObject = {d = {
            superdata = 0xca81a8, stringdata = 0xc661c0 "QCoreApplication", 
            data = 0xc66260, extradata = 0x0}}, static self = 0xbfff0de4}, 
      static staticMetaObject = {d = {superdata = 0xcac7e4, 
          stringdata = 0x1467fa0 "QApplication", data = 0x14681a0, 
          extradata = 0x0}}}, static staticMetaObject = {d = {
        superdata = 0x1630f48, stringdata = 0x596d60 "KApplication", 
        data = 0x596f00, extradata = 0x0}}, static loadedByKdeinit = false, 
    static KApp = 0xbfff0de4, d = 0x9034808}, static staticMetaObject = {d = {
      superdata = 0x60abc0, stringdata = 0x1adca0 "KCMShell", 
      data = 0x1ade60, extradata = 0x0}}, m_serviceName = {
    static null = {<No data fields>}, static shared_null = {ref = {
        _q_value = 2819}, alloc = 0, size = 0, data = 0xcad45a, clean = 0, 
      simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, 
      reserved = 0, array = {0}}, static shared_empty = {ref = {
        _q_value = 63}, alloc = 0, size = 0, data = 0xcad46e, clean = 0, 
      simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, 
      reserved = 0, array = {0}}, d = 0xcad448, 
    static codecForCStrings = 0x0}}
	lang = {static null = {<No data fields>}, static shared_null = {
    ref = {_q_value = 2819}, alloc = 0, size = 0, data = 0xcad45a, clean = 0, 
    simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, 
    reserved = 0, array = {0}}, static shared_empty = {ref = {_q_value = 63}, 
    alloc = 0, size = 0, data = 0xcad46e, clean = 0, simpletext = 0, 
    righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {
      0}}, d = 0x90c0c60, static codecForCStrings = 0x0}
	modules = {{p = {static shared_null = {ref = {_q_value = 563}, 
        alloc = 0, begin = 0, end = 0, sharable = 1, array = {0x0}}, 
      d = 0xcad3d4}, d = 0xcad3d4}}
	kdeargs = (KCmdLineArgs *) 0xbfff0e4c
	options = {d = 0x9005ea8}
	args = (const KCmdLineArgs *) 0x9006200
	serviceName = {static null = {<No data fields>}, 
  static shared_null = {ref = {_q_value = 2819}, alloc = 0, size = 0, 
    data = 0xcad45a, clean = 0, simpletext = 0, righttoleft = 0, 
    asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, 
  static shared_empty = {ref = {_q_value = 63}, alloc = 0, size = 0, 
    data = 0xcad46e, clean = 0, simpletext = 0, righttoleft = 0, 
    asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, d = 0xcad448, 
  static codecForCStrings = 0x0}
	ftype = <value optimized out>
#7  0x0804867b in main (argc=4, argv=0xbfff1034) at kcmshell4_dummy.cpp:3
No locals.