SUID: Drop root permission like Sway about dwl

[djpohly]

Sounds good to me. Send a PR to review?

[sdsddsd1]

I am not able to do this. I just want to ask or encourage the conversation.

[LukasZumvorde]

A pull request has been added trying to copy this feature form Sway #36

[djpohly]

Can someone with this use case test the PR?

[sdsddsd1]

I would test, but I cant build dwl because of missing xwayland. I cannot find a way to disable it in the makefile.

[alex-courtis]

xwayland is not optional; you'll need it to build and run.

[djpohly]

It ought to be optional, really. You shouldn't have to install X11 cruft in order to run dwl.

[djpohly]

Fixed that. @sdsddsd1, give it another try!

[sdsddsd1]

I have no success to start dwl. It cannot become 'drm master' and ends with a segmention fault. There is chmod u+s /usr/bin/dwl.
Here is a strace, if that helps. https://termbin.com/195v

[sdsddsd1]

@LukasZumvorde , I somehow couldnt ping you in the first post.

[sdsddsd1]

Is this feature still relevant? As of linux 5.8 it is possible to become and drop drm_master for unprevileged users. This feature is available in the latest wlroots master. I can run other compositors with setgid on input as a user process.

chown :input /usr/bin/sway
chmod g+s    /usr/bin/sway

I can start also dwl like this, but firefox refuses to start because of allegedly root permissions.

[djpohly]

@sdsddsd1 Do you still have an issue with this on your setup, or did the Linux fix (plus, perhaps, adding your user to the input group) solve it?

[sdsddsd1]

@djpohly : I dont have wayland setup at the moment to test on. My setup was the lines above and to be in the video group. I think I tried with to be in the input group aswell. When I remember right dwl was still started as a root process. My guess is, it does not know how to drop root.

[yellowhat]

Hi,
I have just tried to compile dwl but on running it the tty gets frozen even with:

chown :input dwl
chmod g+s dwl

Does dwl requires to be run as root?

Thanks

[yellowhat]

No having my user part of the input group was the problem.

[djpohly]

I think this was due to missing either the input or video group for the running user, so I'm going to go ahead and close it.