We checked against integer overflow, but not against overflowing the
QByteArray size limit. That caused a std::bad_alloc to be thrown, which
is bad when decoding unknown data. QCborStreamReader wasn't affected,
since it doesn't merge chunks.
Change-Id: I99ab0f318b1c43b89888fffd160c36f495fada87
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
QByteArray doesn't like it.
Apply the same protection to QString, which we know uses the same
backend but uses elements twice as big. That means it can contain
slightly more than half as many elements, but exact half will suffice
for our needs.
Change-Id: Iaa63461109844e978376fffd15f9d4c7a9137856
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>