In Qt 6, QByteArray can hold more than two GiB of data on 64-bit
platforms, so QBuffer should be able to handle writes of more than two
GiB, too. But the implementation didn't check for overflow and held
sizes in int variables, so it happily reported success but wrote data
only mod INT_MAX.
Fix by carefully avoiding overflow and using size variables of proper
type.
[ChangeLog][QtCore][QBuffer] Fixed silent data truncation when writing
more than two GiB at once on 64-bit platforms.
Pick-to: 6.3 6.2
Fixes: QTBUG-102171
Change-Id: Ib666f9f7db24495b4ed64191a48b35edc410f7e9
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
61157c8354