[SRU] fwbuilder crashes in Noble when trying to create almost any type of new object

[Lupe Christoph]

[ Impact ]

fwbuilder will crash immediately if the user tries to create almost any type of new object.

On Noble, even the gnome-shell will crash when fwbuilder crashes and the user will need to login again.

[ Test Plan ]

1. Open fwbuilder
2. Close the Quick Start Guide,.
3. Click on the "New Object" icon.
4. From the popup menu, click on "New Library"

If the package is not fixed then it will crash immediately.

With the fixed package, it will open the screen with the New Library editor.

[ Where problems could occur ]

It is an upstream patch and is just adding a NULL check before the pointer is actually dereferenced. There is no other change in the code. And, so the chances of a regression is very less for this change.

[ Other Info ]

Focal also has the same problem but this patch alone is not fixing the problem with Focal. It will need more changes and it appears it will need fixes in "qtbase-opensource-src".

[ Original Bug Description ]

To reproduce:
* start fwbuilder without any arguments
* click "New Object"
* click any type of object, e.g. "New Library"
* fwbuilder will segfault

Here is the stack trace:
(gdb) where
#0 0x000055555571115e in ?? ()
#1 0x000055555571cc73 in ?? ()
#2 0x0000555555720fc3 in ?? ()
#3 0x00005555559f3825 in ?? ()
#4 0x00007ffff6a49a88 in ?? () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#5 0x00007ffff76a8b86 in QAction::triggered(bool) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#6 0x00007ffff76ab89c in QAction::activate(QAction::ActionEvent) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#7 0x00007ffff78355d2 in ?? () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#8 0x00007ffff783d199 in ?? () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#9 0x00007ffff76f217e in QWidget::event(QEvent*) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#10 0x00007ffff76af6b3 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#11 0x00007ffff76b72e4 in QApplication::notify(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#12 0x00005555559e2dfc in ?? ()
#13 0x00007ffff6a1216a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007ffff76b5dc7 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#15 0x00007ffff770c4b3 in ?? () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#16 0x00007ffff770ec45 in ?? () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#17 0x00007ffff76af6b3 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt5Widgets.so.5
#18 0x00005555559e2dfc in ?? ()
#19 0x00007ffff6a1216a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00007ffff6fa8257 in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) () from /lib/x86_64-linux-gnu/libQt5Gui.so.5
#21 0x00007ffff6f7d9bc in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Gui.so.5
#22 0x00007ffff2d64b9e in ?? () from /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#23 0x00007ffff55258bb in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#24 0x00007ffff5578f08 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#25 0x00007ffff5523003 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#26 0x00007ffff6a6b548 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#27 0x00007ffff6a10a9b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#28 0x00007ffff6a19024 in QCoreApplication::exec() () from /lib/x86_64-linux-gnu/libQt5Core.so.5
#29 0x00005555556744cf in ?? ()
#30 0x00007ffff6324fd0 in __libc_start_call_main (main=main@entry=0x5555556736d3, argc=argc@entry=1, argv=argv@entry=0x7fffffffdd08) at ../sysdeps/nptl/libc_start_call_main.h:58
#31 0x00007ffff632507d in __libc_start_main_impl (main=0x5555556736d3, argc=1, argv=0x7fffffffdd08, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffdcf8) at ../csu/libc-start.c:409
#32 0x00005555556735de in ?? ()

Details:
Package version: 5.3.7-4.1build2
OS: VERSION="21.10 (Impish Indri)"

[Sudip Mukherjee (sudipmuk)]

I can reproduce the error on Focal, Jammy and Mantic. Could not test on Noble as its uninstallable until time_t transition is over.

[Sudip Mukherjee (sudipmuk)]

tested and confirmed that it affects Noble also.

[Sudip Mukherjee (sudipmuk)]

debdiff attached for Noble.

[Sudip Mukherjee (sudipmuk)]

Adding modified debdiff for Noble.

[Sudip Mukherjee (sudipmuk)]

debdiff for Mantic.

[Sudip Mukherjee (sudipmuk)]

debdiff for Jammy.

[Sudip Mukherjee (sudipmuk)]

adding modified Noble debdiff with modified version.

[Sudip Mukherjee (sudipmuk)]

Debdiff for Oracular