Bug#784687: xserver-xorg-core: xhost +si:localuser:foo does not grant access to foo anymore

[Dirk Griesbach <spamthis@freenet.de>]

Package: xserver-xorg-core
Version: 2:1.17.1-2
Severity: normal

Hello,

xhost does not grant access despite claiming otherwise since the upgrade
to 1.17.1.
,----
| $ xhost
| access control enabled, only authorized clients can connect
| SI:localuser:foo
| SI:localuser:bar
`----

,----
| $ su - foo
| Passwort: 
| foo@test:~$ xeyes 
| No protocol specified
| Error: Can't open display: :0.0
`----

However, access is granted if access control is disabled with xhost +x.
Logs don't mention any problem regarding access control.

Thanks,
Dirk

-- Package-specific info:
X server symlink status:
------------------------
lrwxrwxrwx 1 root root 13 Jul 28  2009 /etc/X11/X -> /usr/bin/Xorg
-rwxr-xr-x 1 root root 2544344 Nov 14  2010 /usr/bin/Xorg

VGA-compatible devices on PCI bus:
----------------------------------
00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller [8086:27a2] (rev 03)

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (101, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 4.0.1 (SMP w/2 CPU cores)
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)

Versions of packages xserver-xorg-core depends on:
ii  keyboard-configuration    1.125
ii  libaudit1                 1:2.4-1+b1
ii  libc6                     2.19-18
ii  libdrm2                   2.4.60-3
ii  libegl1-mesa              10.4.2-2
ii  libepoxy0                 1.2-1
ii  libgbm1                   10.4.2-2
ii  libgcrypt20               1.6.3-2
ii  libgl1-mesa-glx [libgl1]  10.4.2-2
ii  libpciaccess0             0.13.3-1
ii  libpixman-1-0             0.32.6-3
ii  libselinux1               2.3-2
ii  libudev1                  215-17
ii  libxau6                   1:1.0.8-1
ii  libxdmcp6                 1:1.1.2-1
ii  libxfont1                 1:1.5.1-1
ii  libxshmfence1             1.2-1
ii  udev                      215-17
ii  xserver-common            2:1.17.1-2

Versions of packages xserver-xorg-core recommends:
ii  libgl1-mesa-dri  10.4.2-2

Versions of packages xserver-xorg-core suggests:
ii  xfonts-100dpi    1:1.0.4
ii  xfonts-75dpi     1:1.0.4
ii  xfonts-scalable  1:1.0.3-1

-- no debconf information