[Bug]: NativeWindowViews::ShouldDescendIntoChildForEventHandling sporadically crashing application when checking BrowserViews for draggable regions

[arctictron]

Preflight Checklist

• I have read the Contributing Guidelines for this project.
• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Electron Version

15.3.0

What operating system are you using?

Windows

Operating System Version

Windows 10 version 21H1

What arch are you using?

x64

Last Known Working Electron version

11.0.3

Expected Behavior

Should return true or false when checking if the click was within a draggable region of a browserview.

Actual Behavior

It appears that sporadically that the view_draggable_region may not be valid, thus when checking if the cursor is contained within the SkRegion by calling SkRegion::contains, an uncaught exception happens that results in electron crashing.

Testcase Gist URL

No response

Additional Information

I believe this is related to issue #31406, as it crashes in the same way. I'm submitting this bug because while I was trying to figure out what was really causing issue 31406 I ran into this one. As a refresher I am using a frameless window with a BrowserView acting as the title bar that has a draggable region, then 1+ other BrowserViews serving the main content that do not have draggable regions. This is interesting because I reverted back to using a window instead of being a frameless and this started to happen, while no longer experiencing the crashes reported in issue 31406. Next I switched to running the title bar code from being in a BrowserView into the main BrowserWindow since it seems to be only BrowserViews that will cause this issue (I could be misunderstanding the underlying code), and the crashes still happen. I have tried this using several versions of electron from 11.x.x, 12.x.x, 13.x.x, and 15.x.x and they all exhibit this behavior, however 11.0.3 is the last working version that does not crash. My guess is that pull 26738 was when this issue, and subsequently issue 31406, was introduced as this bit of code

for (auto* view : browser_views()) { auto* native_view = static_cast<NativeBrowserViewViews*>(view); auto* view_draggable_region = native_view->draggable_region(); if (view_draggable_region && view_draggable_region->contains(location.x(), location.y())) return false; }

is both in NativeWindowViews::ShouldDescendIntoChildForEventHandling and FramelessView::NonClientHitTest.

I still don't have a gist that reproduces either issue, so it could be something else in my application that is causing both issues to crop up. I do have crashdumps that are telling me that these are the last calls in the callstack and that when it calls SkRegion::contains it causes an invalid_read and then crashes due to the uncaught exception.

[codebytere]

could you paste a crash dump?

[arctictron]

After upgrading to version 16 and several weeks of testing, I'm no longer seeing this type of crash. I'm going to close this issue for now.