gsd-backlight-helper spamming the logs since upate to 16.04

[Romano Giannetti]

Since updating to 16.04 from 14.04, I have the syslog spammed by:

SEC: May 22 13:26:43 samsung-romano pkexec[21248]: gdm: Error executing command as another user: Not authorized [USER=root] [TTY=unknown] [CWD=/var/lib/gdm3] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 1766]
SEC: May 22 13:26:43 samsung-romano pkexec: pam_unix(polkit-1:session): session opened for user root by (uid=1153)
SEC: May 22 13:26:43 samsung-romano pkexec: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
SEC: May 22 13:26:43 samsung-romano pkexec: pam_ck_connector(polkit-1:session): cannot determine display-device
SEC: May 22 13:26:43 samsung-romano pkexec[21249]: romano: Executing command [USER=root] [TTY=unknown] [CWD=/home/romano] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 4322]
SYS: May 22 13:26:43 samsung-romano gnome-session[1454]: Error executing command as another user: Not authorized
SYS: May 22 13:26:43 samsung-romano gnome-session[1454]: This incident has been reported.

every couple of seconds or so. There is no really need to change brightness... how can I stop it?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Brett Keller (blkeller)]

I believe this bug has been fixed upstream. Would it be possible to get this patch merged into the Ubuntu package?:
https://git.gnome.org/browse/gnome-settings-daemon/commit/?id=76dab07

[Sebastian Nohn (sebastian-nohn)]

Does not look like this is fixed. I just upgraded from 14.04 to 16.04.1 and my syslog gets spammed with

Nov 21 14:36:09 bnasws02 gnome-session[1536]: Error executing command as another user: Not authorized
Nov 21 14:36:09 bnasws02 gnome-session[1536]: This incident has been reported.
Nov 21 14:36:10 bnasws02 gnome-session[1536]: Error executing command as another user: Not authorized
Nov 21 14:36:10 bnasws02 gnome-session[1536]: This incident has been reported.
Nov 21 14:36:22 bnasws02 gnome-session[1536]: Error executing command as another user: Not authorized
Nov 21 14:36:22 bnasws02 gnome-session[1536]: This incident has been reported.
Nov 21 14:36:23 bnasws02 gnome-session[1536]: Error executing command as another user: Not authorized
Nov 21 14:36:23 bnasws02 gnome-session[1536]: This incident has been reported.
Nov 21 14:36:31 bnasws02 gnome-session[1536]: Error executing command as another user: Not authorized
Nov 21 14:36:31 bnasws02 gnome-session[1536]: This incident has been reported.

my auth.log with:

Nov 21 14:36:43 bnasws02 pkexec[24666]: gdm: Error executing command as another user: Not authorized [USER=root] [TTY=unknown] [CWD=/var/lib/gdm3] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 927]
Nov 21 14:36:43 bnasws02 pkexec: pam_unix(polkit-1:session): session opened for user root by (uid=1000)
Nov 21 14:36:43 bnasws02 pkexec: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
Nov 21 14:36:43 bnasws02 pkexec: pam_ck_connector(polkit-1:session): cannot determine display-device
Nov 21 14:36:43 bnasws02 pkexec[24667]: sebastian: Executing command [USER=root] [TTY=unknown] [CWD=/home/sebastian] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 927]
Nov 21 14:36:47 bnasws02 pkexec[24675]: gdm: Error executing command as another user: Not authorized [USER=root] [TTY=unknown] [CWD=/var/lib/gdm3] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 927]
Nov 21 14:36:47 bnasws02 pkexec: pam_unix(polkit-1:session): session opened for user root by (uid=1000)
Nov 21 14:36:47 bnasws02 pkexec: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
Nov 21 14:36:47 bnasws02 pkexec: pam_ck_connector(polkit-1:session): cannot determine display-device
Nov 21 14:36:47 bnasws02 pkexec[24676]: sebastian: Executing command [USER=root] [TTY=unknown] [CWD=/home/sebastian] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 927]
Nov 21 14:36:50 bnasws02 pkexec[24685]: gdm: Error executing command as another user: Not authorized [USER=root] [TTY=unknown] [CWD=/var/lib/gdm3] [COMMAND=/usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 927]
Nov 21 14:36:50 bnasws02 pkexec: pam_unix(polkit-1:session): session opened for user root by (uid=1000)
Nov 21 14:36:50 bnasws02 pkexec: pam_systemd(polkit-1:session): Cannot create session: Already running in a session
Nov 21 14:36:50 bnasws02 pkexec: pam_ck_connector(polkit-1:session): cannot determine display-device
Nov 21 14:36:50 bnasws02 pkexec[24686]: sebastian: Executing command [USER=root] [TTY=unknown] [CWD=/home/sebastian]...

[Sebastian Nohn (sebastian-nohn)]

As a workaround, add

blacklist acpi_als

to

/etc/modprobe.d/blacklist.conf

From what I read, this auto brightness "feature" sucks anyway, so this may be the best whether you are affected by this bug or not.

[Michael Gratton (mjog)]

I'm getting this on artful at the moment.

[Pen Gale (pengale)]

I'm also seeing this on Artful, despite applying the "blacklist acpi_als" fix.

The messages are as follows:

Sep 25 10:24:30 coyote org.gnome.SettingsDaemon.Power.desktop[1661]: Error executing command as another user: Not authorized
Sep 25 10:24:30 coyote org.gnome.SettingsDaemon.Power.desktop[1661]: This incident has been reported.

This is on an Thinkpad Yoga 14. I did a clean install of Zesty on it earlier this year, switched to the Gnome desktop after the install, and did a dist-upgrade to Artful last month. The problem has been pretty constant through the upgrades.

[Pen Gale (pengale)]

(Also note: I'm at the Ubuntu Rally in New York this week, if anybody wants to poke at my laptop :-) )

[bradley smith (bradley-r-smith)]

I just upgraded to Artful (17.10) and now my syslog is getting spammed with this. On an Asus UX305FA.

[Sven (mcsv)]

same problem here: Artful (17.10), clean install, Lenovo Yoga 14

[Zach Moazeni (zmoazeni)]

I also have a Thinkpad X1 Yoga and I'm getting these errors in Artful. I read somewhere that shutting off this `systemctl stop iio-sensor-proxy.service` stops the log, and it appears to work for me.

You can't disable it directly but I read somewhere that you can replace the systemd unit to noop instead of starting the service.

[Pen Gale (pengale)]

@zmoazeni: Stopping the service does indeed stop the log spam on my machine. Thanks!

[bradley smith (bradley-r-smith)]

This appears to be fixed for me following update to latest release.

:-)
Thanks

Artful
ASUS UX305FA

[Brian Burch (brian-pingtoo)]

upgraded from 17.04 to 17.10 64-bit desktop. ASUS Transformer T300 CHI-FL005H. kernel 4.13.0-32-generic and gnome-settings-daemon 3.26.2-0ubuntu0.1

syslog and journalctl spammed exactly as described - gdm3 and gsd-backlight-helper --set-brightness

I can confirm "systemctl stop iio-sensor-proxy" causes these messages to stop, but less frequent errors from org.gnome.Shell.desktop are logged repeatedly, e.g.

Error.checkin_request.cc(211) failed to get checking response. Fetcher failed. Retrying.

Followed by various other org.gnome.Shell.desktop messages. I can provide a log if they might be useful, but I suspect they are triggered by killing the iio-sensor-proxy and so are probably not very relevant to the original bug.

[Louis Rossouw (lrossouw)]

I see the same errors on Thinkpad Yoga 14 running 18.04.

[Joonas Tuomola (pave99)]

I have billions of

Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: Error executing command as another user: Not authorized
Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: This incident has been reported.
Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: Error executing command as another user: Not authorized
Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: This incident has been reported.
Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: Error executing command as another user: Not authorized
Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: This incident has been reported.
Feb 21 08:39:19 LIFEBOOK org.gnome.SettingsDaemon.Power.desktop[2627]: Error executing command as another user: Not authorized

in the syslog as well. I get these when i try to change brightness using the bar in the top right. Using Fn + F7 works well. If i try to change brightness using terminal command
 "pkexec /usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 0", I get the same result as above. But changing pkexec to sudo fixes the problem.