Details
-
Bug
-
Resolution: Done
-
P1: Critical
-
5.12.3
-
ab933b1c92ec4f39ce280fdf956a4c4a746cf4d9 (qt/qtdeclarative/5.12)
Description
I've recently had lots of crashes in _q_itemsInserted with stack traces like this:
0 Qt5Core.dll + 0x4169ec
eip = 0x672a69ec esp = 0x00f1c290 ebp = 0x14785d68 ebx = 0x0000001a
esi = 0x00000018 edi = 0x00000001 eax = 0x0000001b ecx = 0x230513a8
edx = 0x671bd2ec efl = 0x00010206
Found by: given as instruction pointer in context
1 Qt5Qml.dll!QQmlDelegateModel::_q_itemsInserted(int,int) [qqmldelegatemodel.cpp : 1346 + 0xb]
eip = 0x657f7091 esp = 0x00f1c294 ebp = 0x14785d68
Found by: stack scanning
2 Qt5Qml.dll!QQmlDelegateModel::_q_rowsInserted(QModelIndex const &,int,int) [qqmldelegatemodel.cpp : 1657 + 0x14]
eip = 0x657f7852 esp = 0x00f1c2b8 ebp = 0x14785d68
Found by: call frame info
3 Qt5Qml.dll!QQmlDelegateModel::qt_static_metacall(QObject *,QMetaObject::Call,int,void * *) [moc_qqmldelegatemodel_p.cpp : 198 + 0x1a]
eip = 0x657f46fa esp = 0x00f1c2c8 ebp = 0x14785d68
Found by: call frame info
4 Qt5Qml.dll!QQmlDelegateModel::qt_metacall(QMetaObject::Call,int,void * *) [moc_qqmldelegatemodel_p.cpp : 334 + 0x9]
eip = 0x657ff4e5 esp = 0x00f1c2fc ebp = 0x14785d68
Found by: call frame info
5 Qt5Core.dll!QMetaObject::metacall(QObject *,QMetaObject::Call,int,void * *) [qmetaobject.cpp : 303 + 0x5]
eip = 0x67005848 esp = 0x00f1c320 ebp = 0x00f1c418
Found by: call frame info
6 Qt5Core.dll!QMetaObject::activate(QObject *,int,int,void * *) [qobject.cpp : 3806 + 0x14]
eip = 0x6701cadf esp = 0x00f1c330 ebp = 0x00f1c418
Found by: call frame info
7 Qt5Core.dll!QAbstractItemModel::endInsertRows() [qabstractitemmodel.cpp : 2748 + 0x52]
eip = 0x66fcab28 esp = 0x00f1c3d8 ebp = 0x00000000
Found by: call frame info with scanning
8 Qt5Core.dll!QSortFilterProxyModelPrivate::insert_source_items(QVector<int> &,QVector<int> &,QVector<int> const &,QModelIndex const &,Qt::Orientation,bool) [qsortfilterproxymodel.cpp : 902 + 0x12]
eip = 0x66fe70c9 esp = 0x00f1c434 ebp = 0x00000000
Found by: call frame info
9 Qt5Core.dll!QSortFilterProxyModelPrivate::source_items_inserted(QModelIndex const &,int,int,Qt::Orientation) [qsortfilterproxymodel.cpp : 1013 + 0x15]
eip = 0x66feb0c8 esp = 0x00f1c48c ebp = 0x00f1c688
Found by: stack scanning
10 ntdll.dll + 0x45d3e
eip = 0x76ef5d3e esp = 0x00f1c530 ebp = 0x00f1c6a4
Found by: call frame info with scanning
11 0xf1c688
eip = 0x00f1c688 esp = 0x00f1c6ac ebp = 0x00000000
Found by: previous frame's frame pointer
12 Qt5Core.dll!QSortFilterProxyModelPrivate::insert_source_items(QVector<int> &,QVector<int> &,QVector<int> const &,QModelIndex const &,Qt::Orientation,bool) [qsortfilterproxymodel.cpp : 902 + 0x12]
eip = 0x66fe70c9 esp = 0x00f1c6c0 ebp = 0x00000000
Found by: stack scanning
13 Qt5Core.dll!QSortFilterProxyModelPrivate::source_items_inserted(QModelIndex const &,int,int,Qt::Orientation) [qsortfilterproxymodel.cpp : 1013 + 0x15]
eip = 0x66feb0c8 esp = 0x00f1c718 ebp = 0x00f1c914
Found by: stack scanning
14 Qt5Core.dll!QVector<QVector<QPersistentModelIndexData *> >::reallocData(int,int,QFlags<QArrayData::AllocationOption>) [qvector.h : 625 + 0x13]
eip = 0x66fcdd55 esp = 0x00f1c7f0 ebp = 0x00f1c914
Found by: call frame info with scanning
The reason is use after free of an item that is still hanging around in the loop's cache copy.
Updating the model index like it's done in the loop can also effect the view's layout so destruction of items can happen during the iteration. I've traced the destructor calls to verify this, the item that causes the crash was actually destroyed prior to its use in the loop.
5df747fc5300f9c7e1da0fb86bab68209c921c9c introduced a fix for the insert situation. The same fix can be applied here: Check if the item is still in the actual cache before accessing it.
I'll submit a patch on gerrit for review later.