Given the right combination of ThinkPad and X.org, just reading the video
output control state is enough to hard-crash X.org.
Until the day I somehow find out a model or BIOS cut date to not provide this
feature to ThinkPads that can do video switching through X RandR, change
permissions so that only processes with CAP_SYS_ADMIN can access any sort of
video output control state.
This bug could be considered a local DoS I suppose, as it allows any
non-privledged local user to cause some versions of X.org to hard-crash some
Reported-by: Jidanni <firstname.lastname@example.org>
Signed-off-by: Henrique de Moraes Holschuh <email@example.com>