Samuel Holland <samuel_at_sholland.org> wrote:
> It also works if X has permission to open the tty device read/write. Opening a
> tty as a session leader without a controlling terminal will set the controlling
> terminal to that tty. Relevant kernel code:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/tty/tty_jobctrl.c?h=v5.17#n129
>
> And X will try to do that at startup (after failing to play with process groups
> because it is already group leader):
>
> https://gitlab.freedesktop.org/xorg/xserver/-/blob/master/hw/xfree86/os-support/linux/lnx_init.c#L207
>
> I use a udev rule to set the tty owner:
>
> $ cat /etc/udev/rules.d/99-tty.rules
> SUBSYSTEM=="tty", KERNEL=="tty1", OWNER="samuel", GROUP="samuel", MODE="0600"
>
> And everything Just Works.
I currently have my tty owned by me whenever I login, with the group
set to tty. The permissions are 600, so I would expect it to work
as long as I run X as my user, right? Unfortunately, I tried:
s6-setsid X :3 vt3
(on tty3), and had the same issue. It's still trying to switch the vt.
Would I have to switch the group as well? It seems that wouldn't
grant any additional privileges, especially since I am in the same
(supplementary) group as the tty?
It seems like a good option, I'm just unsure why it's not working?
Thanks!
--Dallin
Received on Sat May 28 2022 - 06:07:48 CEST