RFR: 8330936: [ubsan] exclude function BilinearInterp and ShapeSINextSpan in libawt java2d from ubsan checks

[Christoph Langer]

On Thu, 23 Jan 2025 09:23:52 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

> In java2d coding there are a few overflows (those are shown when running jtreg tests with ubsan enabled binaries) 
> jtreg test java/awt/Scrollbar/AquaLFScrollbarTest/ScrollBarBorderTest.java shows
> 
> jdk/src/java.desktop/share/native/libawt/java2d/loops/TransformHelper.c:683:16: runtime error: signed integer overflow: 1651910497 + 660764199 cannot be represented in type 'int'
>     #0 0x7efe59e6ece8 in BilinearInterp src/java.desktop/share/native/libawt/java2d/loops/TransformHelper.c:683
>     #1 0x7efe59e75e21 in Java_sun_java2d_loops_TransformHelper_Transform src/java.desktop/share/native/libawt/java2d/loops/TransformHelper.c:499
>     #2 0x7efe9b8dee7b (<unknown module>)
> 
> java/awt/BasicStroke/DashStrokeTest.java shows
> 
> src/java.desktop/share/native/libawt/java2d/pipe/ShapeSpanIterator.c:1366:21: runtime error: signed integer overflow: 128253951 + 2118518271 cannot be represented in type 'int'
>     #0 0x7fb97d7daf21 in ShapeSINextSpan src/java.desktop/share/native/libawt/java2d/pipe/ShapeSpanIterator.c:1366
>     #1 0x7fb97d62fa7e in AnyIntSetSpans src/java.desktop/share/native/libawt/java2d/loops/AnyInt.c:75
>     #2 0x7fb97d6a8816 in Java_sun_java2d_loops_FillSpans_FillSpans src/java.desktop/share/native/libawt/java2d/loops/FillSpans.c:92
>     #3 0x7fba12d07e7b (<unknown module>)
> 
> 
> There is currently no need seen to adjust this coding, so exclude the methods from ubsan checking to avoid unneeded warnings.

LGTM now with the updated bug synopsis. But somebody from client-libs has to give their blessings as well.

-------------

Marked as reviewed by clanger (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/23255#pullrequestreview-2581615307