Debian/Ubuntu - Can't open session after update to 0.10

[troffasky]

I am not able to open a session after updating from 0.9.19 to 0.10.0. I know that the session is running because I can see all the expected processes running for that user.
In particular, this is logged whilst the session is failing to open:

[2024-07-25T22:08:10.986+0100] [WARN ] xrdp_wm_log_msg: 'ip' is not needed for this connection - please remove
[2024-07-25T22:08:10.989+0100] [DEBUG] xrdp_wm_log_msg: connecting to sesman on sesman.socket
[2024-07-25T22:08:10.992+0100] [WARN ] Ignoring obsolete SCP port value '3350'
[2024-07-25T22:08:10.994+0100] [INFO ] xrdp_wm_log_msg: sesman connect ok
[2024-07-25T22:08:10.999+0100] [INFO ] xrdp_wm_log_msg: Performing login request for pikiosk
[2024-07-25T22:08:11.270+0100] [DEBUG] xrdp_wm_log_msg: sending login info to session manager, please wait...
[2024-07-25T22:08:11.553+0100] [DEBUG] Login state has changed to WMLS_CONNECT_IN_PROGRESS
[2024-07-25T22:08:11.888+0100] [ERROR] dynamic_monitor_open_response: error
[2024-07-25T22:08:11.115+0100] [ERROR] xrdp_rdp_recv: xrdp_channel_process failed
[2024-07-25T22:08:11.555+0100] [INFO ] xrdp_wm_log_msg: login was successful - creating session
[2024-07-25T22:08:11.583+0100] [DEBUG] xrdp_wm_log_msg: sending create session request to session manager. Please wait...
[2024-07-25T22:08:11.671+0100] [INFO ] xrdp_wm_log_msg: session is available on display 12 for user pikiosk
[2024-07-25T22:08:11.754+0100] [INFO ] loaded module 'libxup.so' ok, interface size 10416, version 4
[2024-07-25T22:08:11.782+0100] [DEBUG] xrdp_wm_log_msg: started connecting
[2024-07-25T22:08:11.809+0100] [INFO ] lib_mod_connect: connecting via UNIX socket
[2024-07-25T22:08:13.835+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:15.903+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:17.111+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:19.113+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:21.124+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:23.135+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:25.149+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:27.153+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:29.156+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:31.166+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:33.191+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:35.202+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:37.206+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:39.228+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:41.841+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:41.114+0100] [DEBUG] Closed socket 25 (AF_UNIX)
[2024-07-25T22:08:41.117+0100] [DEBUG] xrdp_wm_log_msg: connection problem, giving up
[2024-07-25T22:08:41.120+0100] [DEBUG] xrdp_wm_log_msg: some problem
[2024-07-25T22:08:41.125+0100] [ERROR] xrdp_wm_log_msg: Error connecting to user session
[2024-07-25T22:08:41.127+0100] [DEBUG] xrdp_mm_module_cleanup

What is the socket it's trying to open here? Connection to xrdp-sesman?

[2024-07-25T22:08:10.994+0100] [INFO ] Socket 13: connection accepted from AF_UNIX
[2024-07-25T22:08:11.554+0100] [INFO ] Received system login request from xrdp for user: pikiosk IP: ::ffff:192.168.1.2
[2024-07-25T22:08:11.118+0100] [INFO ] starting xrdp-sesexec with pid 1654984
[2024-07-25T22:08:11.498+0100] [INFO ] TerminalServerUsers group tsusers doesn't exist. Access granted for pikiosk
[2024-07-25T22:08:11.527+0100] [INFO ] Access permitted for user: pikiosk
[2024-07-25T22:08:11.555+0100] [INFO ] Received sys login status for pikiosk : logged in
[2024-07-25T22:08:11.610+0100] [INFO ] Received request from xrdp to create a session for user pikiosk
[2024-07-25T22:08:11.637+0100] [INFO ] ++ reconnected session: username pikiosk, display :12.0, session_pid 3627895
[2024-07-25T22:08:11.642+0100] [INFO ] Starting session reconnection script on display 12: /etc/xrdp/reconnectwm.sh
[2024-07-25T22:08:11.671+0100] [INFO ] xrdp-sesexec pid 1654984 is now logging out

[akarl10]

As far as I know "vanilla" xrdp still users root for xrdp to xrdp-sesman and xrdp to x11 connection, but now you could configure xrdp to use different users and groups.

Could you check if in /etc/xrdp/xrdp.ini runtime_user and runtime_group are set to something? If that is the case /etc/xrdp/sesman.ini must have a matching SessionSockdirGroup to the same group as runtime_group, else xup/xrdp is unable to connect to the X server

[troffasky]

runtime does not appear in either sesman.ini, xrdp.ini or xrdp.ini.dpkg-dist [I have installed from Debian packages]. Not mentioned in man xrdp.ini either.
But you could be on to something here, xrdp is running as xrdp and xrdp-sesman is running as root.

[akarl10]

ah, ok. then you are still using xrdp.service from debian I suppose. The simplest thing to do is setting SessionSockdirGroup=xrdp under the [Security] section in sesman.ini.

this is because now sesman sets the group id explicitly, where debian's previous attempt to do the same externally depended on a sticky group bit in the directory permission of /run/xrdp/sockdir

[troffasky]

Praise be! It works!

[alexmyczko]

I'm here because of this https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1076815
is this still an issue with the latest version in sid?

[matt335672]

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