Package: gnome-shell-common Version: 3.38.6-1~deb11u1 Severity: normal Tags: patch
Dear Maintainer, TL;DR: org.gnome.Shell@x11.service wants to restart after 0ms, but fails - filling disk. Please increase to at least a few milliseconds. *** Reporter, please consider answering these questions, where appropriate *** * What led up to the situation? I think the X server was killed, pulseaudio logged: pulseaudio[350117]: X connection to :1 broken (explicit kill or server shutdown). Then org.gnome.Shell@x11.service wanted to restart and RestartSec=0ms in /lib/systemd/user/org.gnome.Shell@x11.service causes filled logs. This happens "sometimes" in our computer labs (we have about 100 student computers). * What exactly did you do (or not do) that was effective (or ineffective)? Don't know exactly what happened, but the result log spamming is a DoS. * What was the outcome of this action? This time - during the first ~2 minutes, the following log message was repeated 4 million times (half a gigabyte) before giving up: 2022-05-05T09:39:17+02:00 ochre systemd[350085]: org.gnome.Shell@x11.service: Stop job pending for unit, delaying automatic restart. 2022-05-05T09:39:17+02:00 ochre systemd[350085]: org.gnome.Shell@x11.service: Stop job pending for unit, delaying automatic restart. ... 4 million identical lines later ... 2022-05-05T09:41:29+02:00 ochre systemd[350085]: org.gnome.Shell@x11.service: Stop job pending for unit, delaying automatic restart. 2022-05-05T09:41:29+02:00 ochre systemd[350085]: org.gnome.Shell@x11.service: Stop job pending for unit, delaying automatic restart. 2022-05-05T09:41:29+02:00 ochre systemd[350085]: Looping too fast. Throttling execution a little. 2022-05-05T09:41:29+02:00 ochre systemd[1]: user@{user-id}.service: State 'stop-sigterm' timed out. Killing. 2022-05-05T09:41:29+02:00 ochre systemd[1]: user@{user-id}.service: Killing process 350085 (systemd) with signal SIGKILL. 2022-05-05T09:41:29+02:00 ochre systemd[1]: user@{user-id}.service: Killing process 350506 (gsd-smartcard) with signal SIGKILL. ... more processes killed ... /lib/systemd/user/org.gnome.Shell@x11.service has: # Do not wait before restarting the shell RestartSec=10ms # Kill any stubborn child processes after this long TimeoutStopSec=5 My guess is that it took 2 minutes to give up instead of 5 seconds, because it was busy spamming these log messages. * What outcome did you expect instead? "A few" log messages before giving up. Attached is a patch to change from 0ms to 10ms, which should give no user-noticable slowdown but would in this case reduce the amount of log messages from 4 million to either about 13k (100/s for just over 2 minutes) or to 500 (100/s for 5s if it gives up when it should). The patch does not fix the original problem, but should reduce problems caused by it. -- System Information: Debian Release: 11.3 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 5.10.0-14-amd64 (SMP w/12 CPU threads) Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_CPU_OUT_OF_SPEC, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set Shell: /bin/sh linked to /usr/bin/bash Init: systemd (via /run/systemd/system) Versions of packages gnome-shell-common depends on: ii dconf-gsettings-backend [gsettings-backend] 0.38.0-2 gnome-shell-common recommends no packages. gnome-shell-common suggests no packages. -- no debconf information
--- org.gnome.Shell@x11.service-orig 2022-05-05 10:24:01.996927942 +0200 +++ org.gnome.Shell@x11.service 2022-05-05 10:24:21.300877802 +0200 @@ -34,6 +34,6 @@ # On X11 we want to restart on-success (Alt+F2 + r) and on-failure. Restart=always # Do not wait before restarting the shell -RestartSec=0ms +RestartSec=10ms # Kill any stubborn child processes after this long TimeoutStopSec=5