Created attachment 188395 [details]
Patch

Bug Report: KWin Wayland Segmentation Fault on USB-C Dock Unplug

Product: KWin
Component: wayland-generic
Summary: KWin crashes with SIGSEGV when unplugging a USB-C dock in Wayland session.

Description:
KWin crashes with a segmentation fault when unplugging a USB-C dock from the laptop. This occurs consistently during hot-unplug events. The crash happens in the color management protocol handling, specifically in wp_color_manager_v1_get_output when attempting to access a removed output resource.

Steps to Reproduce:
1. Connect a USB-C dock with displays to the laptop.
2. Log in to a Wayland Plasma session.
3. Unplug the USB-C dock.
4. KWin crashes with SIGSEGV.

Expected Behavior:
Unplugging the dock should not cause a crash; the system should handle hot-unplug gracefully.

Actual Behavior:
KWin crashes, requiring a session restart.

System Information:
Operating System: Debian Trixie (unstable)
Kernel Version: 6.12.57+deb13-amd64
Architecture: x86_64
Graphics Driver: Mesa 25.0.7-2
KWin Version: 6.3.7
Qt Version: 6.x
Wayland Server Library: libwayland-server.so.0

Additional Notes:
- Crash log attached (crash.log).
- Proposed fix: Add validity check for output in ColorManagerV1::wp_color_manager_v1_get_output to prevent access to removed outputs.
- Patch attached (patch.diff).
- System info attached (system_info.txt).
- Similar issues: Related to bugs 446124, 448778, 511632 (crashes on unplug, but different stack traces).

Attachments:
- crash.log: Full crash backtrace.
- patch.diff: Git diff for the proposed fix.
- system_info.txt: Detailed system information.

Submit to: https://bugs.kde.org/enter_bug.cgi?product=kwin&component=wayland-generic