diff options
author | Lars Knoll <lars.knoll@qt.io> | 2020-05-29 10:24:31 +0200 |
---|---|---|
committer | Lars Knoll <lars.knoll@qt.io> | 2020-05-29 23:21:51 +0200 |
commit | f98fe1ba41002f936aa2fc3dac0f7b27fc290938 (patch) | |
tree | 0d6734f1ed1be8cc0d308307b15e75e80fabc928 /src/widgets/graphicsview | |
parent | d4ff606941704ef2dd7520a0c81c982a5a0b0f73 (diff) |
Fix UB in QGraphicsScene::wheelEvent()
operator--() would iterate before begin() if the
list was empty. This is UB, and will crash in Qt 6,
where begin()/end() can return an iterator pointing
to a nullptr if the list is empty.
Change-Id: I39c3a8ebb09fcad75d42019b02426ac5ac05eed9
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>
Reviewed-by: MÃ¥rten Nordheim <marten.nordheim@qt.io>
Diffstat (limited to 'src/widgets/graphicsview')
-rw-r--r-- | src/widgets/graphicsview/qgraphicsscene.cpp | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/src/widgets/graphicsview/qgraphicsscene.cpp b/src/widgets/graphicsview/qgraphicsscene.cpp index d5ab1afd92..ba115b7485 100644 --- a/src/widgets/graphicsview/qgraphicsscene.cpp +++ b/src/widgets/graphicsview/qgraphicsscene.cpp @@ -4101,7 +4101,8 @@ void QGraphicsScene::wheelEvent(QGraphicsSceneWheelEvent *wheelEvent) // Remove all popups after the one found, or all or them if no popup is under the mouse. // Then continue with the event. QList<QGraphicsWidget *>::const_iterator iter = d->popupWidgets.constEnd(); - while (--iter >= d->popupWidgets.constBegin() && !wheelCandidates.isEmpty()) { + while (iter > d->popupWidgets.constBegin() && !wheelCandidates.isEmpty()) { + --iter; if (wheelCandidates.first() == *iter || (*iter)->isAncestorOf(wheelCandidates.first())) break; d->removePopup(*iter); |