x11-common: duplicate calls to xhost in /etc/X11/Xsession.d scripts

[Stefan Puiu]

Hi,

While debugging a different issue (see https://askubuntu.com/questions/1280861/black-screen-after-18-04-20-04-1-upgrade-on-virtualbox), I was trying to understand who runs 'xhost +si:localuser:<myuser>' and found the scripts in /etc/X11/Xsession.d. There I noticed there are 2 scripts who end up calling xhost like this, with slightly different tweaks:

stefan@spuiu-vm:~$ grep -rn xhost /etc/X11/Xsession.d/
/etc/X11/Xsession.d/35x11-common_xhost-local:3:# If xhost (from x11-xserver-utils) is installed, use it to give access
/etc/X11/Xsession.d/35x11-common_xhost-local:5:# Unlike other uses of xhost, this is safe since the kernel can check
/etc/X11/Xsession.d/35x11-common_xhost-local:8:if type xhost >/dev/null 2>&1; then
/etc/X11/Xsession.d/35x11-common_xhost-local:9: xhost +si:localuser:$(id -un) || :
/etc/X11/Xsession.d/60x11-common_localhost:3:[ -x /usr/bin/xhost ] && [ -x /usr/bin/id ] &&
/etc/X11/Xsession.d/60x11-common_localhost:4: xhost +si:localuser:`id -un` > /dev/null

It looks to me like one of them could be easily deleted. I'd vote for keeping the first one, 'type <command>' seems a tad more sensible than '-x /usr/bin/<command>', and also the first one makes sure there's no error exit status.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: x11-common 1:7.7+19ubuntu14
ProcVersionSignature: Ubuntu 4.15.0-118.119-generic 4.15.18
Uname: Linux 4.15.0-118-generic x86_64
.tmp.unity_support_test.1:

ApportVersion: 2.20.11-0ubuntu27.9
Architecture: amd64
BootLog:

CasperMD5CheckResult: skip
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: GNOME-Flashback:GNOME
Date: Thu Oct 8 09:29:46 2020
Dependencies: lsb-base 11.1.0ubuntu2
DistUpgraded: 2020-10-07 14:26:33,076 ERROR got error from PostInstallScript ./xorg_fix_proprietary.py (g-exec-error-quark: Failed to execute child process “./xorg_fix_proprietary.py” (No such file or directory) (8))
DistroCodename: focal
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard: InnoTek Systemberatung GmbH VirtualBox Graphics Adapter [80ee:beef] (prog-if 00 [VGA controller])
InstallationDate: Installed on 2014-06-12 (2309 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
Lsusb: Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Lsusb-t: /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ohci-pci/12p, 12M
MachineType: innotek GmbH VirtualBox
PackageArchitecture: all
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-118-generic root=UUID=10a5a28d-f5fd-4e54-b4f5-ae3421877df4 ro find_preseed=/preseed.cfg auto noprompt priority=critical locale=en_US quiet
SourcePackage: xorg
UpgradeStatus: Upgraded to focal on 2020-10-07 (0 days ago)
dmi.bios.date: 12/01/2006
dmi.bios.vendor: innotek GmbH
dmi.bios.version: VirtualBox
dmi.board.name: VirtualBox
dmi.board.vendor: Oracle Corporation
dmi.board.version: 1.2
dmi.chassis.type: 1
dmi.chassis.vendor: Oracle Corporation
dmi.modalias: dmi:bvninnotekGmbH:bvrVirtualBox:bd12/01/2006:svninnotekGmbH:pnVirtualBox:pvr1.2:rvnOracleCorporation:rnVirtualBox:rvr1.2:cvnOracleCorporation:ct1:cvr:
dmi.product.family: Virtual Machine
dmi.product.name: VirtualBox
dmi.product.version: 1.2
dmi.sys.vendor: innotek GmbH
version.compiz: compiz 1:0.9.14.1+20.04.20200211-0ubuntu1
version.libdrm2: libdrm2 2.4.101-2
version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.8-0ubuntu1~20.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx 20.0.8-0ubuntu1~20.04.1
version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2.4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.6-1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1
xserver.bootTime: Thu Oct 8 09:26:12 2020
xserver.configfile: default
xserver.errors:
 Failed to load module "vboxvideo" (module does not exist, 0)
 Failed to load module "vboxvideo" (module does not exist, 0)
 modeset(0): glamor initialization failed
xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.20.8-2ubuntu2.4
xserver.video_driver: modeset

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1576454, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.