Fix StylusPointPropertyInfo crash from invalid HID min/max values

[sleman]

Summary

WPF applications crash with an ArgumentException in StylusPointPropertyInfo on touch-enabled devices whose HID descriptors report Logical Maximum < Logical Minimum (e.g. 0xFF interpreted as signed -1). This affects both the WM_POINTER and WISP stylus stacks, making touch input completely unusable on affected hardware.

This is a common issue on Surface Pro devices with Snapdragon/ARM processors and other modern touch-enabled Windows devices.

Root cause

The StylusPointPropertyInfo constructor validates maximum >= minimum and throws if not. Both stylus stacks pass hardware-reported values directly to this constructor without checking the range:

• WM_POINTER stack: PointerStylusPointPropertyInfoHelper.CreatePropertyInfo() passes prop.logicalMin/prop.logicalMax
• WISP stack: PenContext.InitStylusPointDescription() passes min/max from GetPacketPropertyInfo()

Fix

Swap min/max when the hardware reports them inverted, at both call sites. This preserves the range magnitude, avoids changing the public API, and allows touch input to function correctly.

For the WM_POINTER stack, the resolution calculation is also updated to use the corrected values.

Affected devices

• Microsoft Surface Pro 9, 10, 11th Edition (Snapdragon/ARM variants)
• Other Snapdragon ARM-based Windows devices
• Any device whose touch digitizer HID descriptor has Logical Maximum < Logical Minimum

Affected issues

• Fixes WPF touch function does not work. #7069
• Fixes WPF Crash on modern Touchscreen when EnablePointerSupport is enabled #8435
• Fixes WPF StylusPointPropertyInfo may throw ArgumentException in some machine #8826

[sleman]

@dotnet-policy-service agree [company="{Lumasoft LLC}"]

[Copilot]

Pull request overview

Fixes a crash in WPF’s stylus/touch input stacks caused by some devices reporting inverted HID logical min/max values (logical maximum < logical minimum), which can trigger StylusPointPropertyInfo constructor validation and crash on first touch/stylus interaction.

Changes:

• WISP stack: swap min/max from GetPacketPropertyInfo when inverted before creating StylusPointPropertyInfo.
• WM_POINTER stack: swap logicalMin/logicalMax when inverted and use the corrected values for both resolution calculation and StylusPointPropertyInfo construction.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Input/Stylus/Wisp/PenContext.cs	Normalizes inverted min/max from WISP packet properties to prevent StylusPointPropertyInfo exceptions.
src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Input/Stylus/Pointer/PointerStylusPointPropertyInfoHelper.cs	Normalizes inverted logical min/max from WM_POINTER device properties and ensures downstream computations use corrected values.

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[sleman]

@dotnet-policy-service agree