Fix use-after-free crash in BrowserView.get_instance on macOS#1797
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smparkes wants to merge 2 commits intor0x0r:masterfrom
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Fix use-after-free crash in BrowserView.get_instance on macOS#1797smparkes wants to merge 2 commits intor0x0r:masterfrom
smparkes wants to merge 2 commits intor0x0r:masterfrom
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Hmmm ... not sure about Comprehensive CI / macOS (pull_request)Cancelled after 20m Timeout? |
- Replace OpenFolderDialog's FileDialogNative internals with FolderBrowserDialog
(FileDialogNative+IFileDialog doesn't exist in .NET 8)
- Update WebView2 DLLs from 1.0.2957 (.NET Framework) to 1.0.3240 (netcoreapp3.0)
(old DLLs reference System.Windows.Forms.ContextMenu, removed in .NET 6+)
- Skip .NET Framework registry check in _is_chromium() when using coreclr
- Add explicit clr.AddReference('Microsoft.Win32.SystemEvents') for coreclr
(not auto-loaded like on netfx)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
On macOS ARM64, the app crashes with EXC_BREAKPOINT (SIGTRAP, pointer authentication trap) in object_getClass when a deferred Cocoa callback (performSelectorOnMainThread) fires after a window has been destroyed. Root cause: get_instance iterates BrowserView.instances comparing each instance's .window attribute against a target NSWindow. When a window has been destroyed (windowWillClose_ releases the window), the .window attribute points to freed memory. Comparing it triggers object_getClass on the freed pointer, which fails the ARM64 pointer authentication check and kills the process. The original code had two bugs: 1. Used bare getattr(i, attr) — crashes if the attribute value is a freed Cocoa object whose __eq__ triggers object_getClass 2. Caught only AttributeError and used break — stops searching on any missing attribute, missing valid instances later in the dict Fix get_instance to: - Use getattr(i, attr, None) with a None check to skip freed/cleared attributes without comparing them - Catch all exceptions (not just AttributeError) during comparison - Continue iterating instead of breaking, so later valid instances are still found Also fix windowWillClose_ to: - Clear the window delegate (setDelegate_(None)) before releasing, preventing further delegate callbacks on the freed window - Guard against missing instance (if not i: return) - Guard webview access (if i.webview:) before cleanup And fix windowShouldClose_ to return YES if instance not found. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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On macOS ARM64, the app crashes with EXC_BREAKPOINT (SIGTRAP, pointer authentication trap) in object_getClass when a deferred Cocoa callback (performSelectorOnMainThread) fires after a window has been destroyed.
Root cause: get_instance iterates BrowserView.instances comparing each instance's .window attribute against a target NSWindow. When a window has been destroyed (windowWillClose_ releases the window), the .window attribute points to freed memory. Comparing it triggers object_getClass on the freed pointer, which fails the ARM64 pointer authentication check and kills the process.
The original code had two bugs:
Fix get_instance to:
Also fix windowWillClose_ to:
And fix windowShouldClose_ to return YES if instance not found.