Avoid UBSan negative double -> unsigned int conversion

...during CppunitTest_sc_subsequent_export_test:

> /sc/source/filter/excel/xlescher.cxx:116:43: runtime error: -764.94 is outside the range of representable values of type 'unsigned int'
>     #0 0x2b30c609bf3b in (anonymous namespace)::lclGetRowFromY(ScDocument const&, short, unsigned int&, unsigned int&, unsigned int, unsigned int, long&, long, double) /sc/source/filter/excel/xlescher.cxx:116:43
>     #1 0x2b30c609b1ff in XclObjAnchor::SetRect(XclRoot const&, short, tools::Rectangle const&, MapUnit) /sc/source/filter/excel/xlescher.cxx:174:5
>     #2 0x2b30c4e4c027 in XclExpDffSheetAnchor::ImplCalcAnchorRect(tools::Rectangle const&, MapUnit) /sc/source/filter/excel/xeescher.cxx:308:14
>     #3 0x2b30c4e4b4f4 in XclExpDffAnchorBase::WriteData(EscherEx&, tools::Rectangle const&) /sc/source/filter/excel/xeescher.cxx:277:5
>     #4 0x2b306e07562c in EscherExHostAppData::WriteClientAnchor(EscherEx&, tools::Rectangle const&) /include/filter/msfilter/escherex.hxx:958:51
>     #5 0x2b306e14480f in ImplEESdrWriter::ImplWriteShape(ImplEESdrObject&, EscherSolverContainer&, bool) /filter/source/msfilter/eschesdo.cxx:677:28
>     #6 0x2b306e14cabe in ImplEESdrWriter::ImplWritePage(EscherSolverContainer&) /filter/source/msfilter/eschesdo.cxx:827:13
>     #7 0x2b306e14e881 in ImplEESdrWriter::ImplWriteCurrentPage() /filter/source/msfilter/eschesdo.cxx:909:5
>     #8 0x2b306e14ed51 in EscherEx::AddSdrPage(SdrPage const&) /filter/source/msfilter/eschesdo.cxx:922:28
>     #9 0x2b30c4e89c21 in XclExpObjectManager::ProcessDrawing(SdrPage const*) /sc/source/filter/excel/xeescher.cxx:1807:21
>     #10 0x2b30c4831460 in ExcTable::FillAsTableXml() /sc/source/filter/excel/excdoc.cxx:630:47
>     #11 0x2b30c4837c43 in ExcDocument::ReadDoc() /sc/source/filter/excel/excdoc.cxx:747:23
>     #12 0x2b30c5463fac in XclExpXmlStream::exportDocument() /sc/source/filter/excel/xestream.cxx:1103:18
>     #13 0x2b3070c004e4 in oox::core::FilterBase::filter(com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> const&) /oox/source/core/filterbase.cxx:492:49
>     #14 0x2b30c670399c in oox::xls::ExcelFilter::filter(com::sun::star::uno::Sequence<com::sun::star::beans::PropertyValue> const&) /sc/source/filter/oox/excelfilter.cxx:235:27
>     #15 0x2b3091e831fb in SfxObjectShell::ExportTo(SfxMedium&) /sfx2/source/doc/objstor.cxx:2451:25
>     #16 0x2b3091e7237c in SfxObjectShell::SaveTo_Impl(SfxMedium&, SfxItemSet const*) /sfx2/source/doc/objstor.cxx:1543:19
>     #17 0x2b3091e856ff in SfxObjectShell::DoSaveAs(SfxMedium&) /sfx2/source/doc/objstor.cxx:1922:17
>     #18 0x2b308e173ff9 in ScBootstrapFixture::saveAndReload(ScDocShell*, rtl::OUString const&, rtl::OUString const&, rtl::OUString const&, SfxFilterFlags) /sc/qa/unit/helper/qahelper.cxx:677:13
>     #19 0x2b308e17632f in ScBootstrapFixture::saveAndReload(ScDocShell*, int) /sc/qa/unit/helper/qahelper.cxx:699:28
>     #20 0x2b3067b71c92 in ScExportTest::testTdf135828_Shape_Rect() /sc/qa/unit/subsequent_export-test.cxx:5289:28

(see
<https://lists.freedesktop.org/archives/libreoffice/2020-August/085797.html>
"[global-libreoffice-ci] UBSAN Linux Build - Build # 1738 - Failure!")  As an
uneducated guess, restrict the rnOffset value to >= 0 on the basis that both
Calc and Excel reportedly require drawing elements to have non-negative
positions.

Change-Id: If687b467421437a6b448060fdbc3206b83917c40
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/101979
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

0 files changed, 0 insertions, 0 deletions