Bug#1116643: UBSAN: shift-out-of-bounds in .../drivers/gpu/drm/display/drm_dp_mst_topology.c (shift exponent -1)

[Vincent Lefevre <vincent@vinc17.net>]

On 2025-09-29 17:56:05 +0200, Vincent Lefevre wrote:
> Sep 29 10:01:20 qaa kernel: UBSAN: shift-out-of-bounds in /build/reproducible-path/linux-6.16.8/drivers/gpu/drm/display/drm_dp_mst_topology.c:4574:36

shift-out-of-bounds in drm_dp_mst_topology.c has already been reported
several times in the past, everying involving suspend/resume or
plugging/unplugging a USB-C dock:

2022-12:
https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1970495/comments/25
"Window manager freezes when plugging in USB-C dock with external monitor…"

2023-03 (for the comment about this error):
https://github.com/NixOS/nixpkgs/issues/36392#issuecomment-1461490967
"not sure if related, but saw some new errors popping up when connecting
usb c stuff"

2023-11:
https://forums.linuxmint.com/viewtopic.php?t=407900
"Cinnamon freezes when unsuspending"

2024-04:
https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe-6.5/+bug/2061091
"Sometimes, when trying to shut down or suspend my laptop, it gets stuck
on the console screen"

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / Pascaline project (LIP, ENS-Lyon)