[Bug 1863239] [NEW] /dev/bus/usb/*/* device file of HP multi-function printer assigned to "audio" group

[Till Kamppeter]

Public bug reported:

When testing HPLIP I found out that CUPS backends can access my printer
only when they are running as root, when they are running as the special
user lp, as it is usually the case, they cannot access the printer.

So I tried to find out why and saw that the /dev/bus/usb/*/* device file
for the printer has group ownership "audio" and not "lp":

till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ ll /dev/bus/usb/*/*
crw-rw-r--  1 root root    189,   0 Feb 11 14:17 /dev/bus/usb/001/001
crw-rw-r--  1 root root    189,   2 Feb 11 14:17 /dev/bus/usb/001/003
crw-rw-r--  1 root root    189,   3 Feb 11 14:17 /dev/bus/usb/001/004
crw-rw-r--  1 root plugdev 189,   4 Feb 14 12:23 /dev/bus/usb/001/005
crw-rw-r--  1 root root    189,   5 Feb 11 14:17 /dev/bus/usb/001/006
crw-rw----+ 1 root audio   189,  62 Feb 14 12:37 /dev/bus/usb/001/063
crw-rw-r--  1 root root    189, 128 Feb 11 14:17 /dev/bus/usb/002/001
crw-rw-r--  1 root root    189, 130 Feb 13 09:38 /dev/bus/usb/002/003
till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$

The printer is the device /dev/bus/usb/001/063:

till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ lsusb
Bus 002 Device 003: ID 0b95:1790 ASIX Electronics Corp. AX88179 Gigabit Ethernet
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 138a:0097 Validity Sensors, Inc. 
Bus 001 Device 004: ID 04f2:b5ce Chicony Electronics Co., Ltd Integrated Camera
Bus 001 Device 003: ID 8087:0a2b Intel Corp. 
Bus 001 Device 006: ID 056a:50b7 Wacom Co., Ltd Pen and multitouch sensor
Bus 001 Device 063: ID 03f0:7a12 HP, Inc HP OfficeJet Pro 8730
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ 

There must be a bug somewhere in the UDEV rules.

** Affects: pulseaudio (Ubuntu)
     Importance: High
         Status: New

** Affects: systemd (Ubuntu)
     Importance: High
         Status: New

** Affects: udev (Ubuntu)
     Importance: High
         Status: New

** Description changed:

  When testing HPLIP I found out that CUPS backends can access my printer
  only when they are running as root, when they are running as the special
  user lp, as it is usually the case, they cannot access the printer.
  
  So I tried to find out why and saw that the /dev/bus/usb/*/* device file
  for the printer has group ownership "audio" and not "lp":
  
  till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ ll /dev/bus/usb/*/*
  crw-rw-r--  1 root root    189,   0 Feb 11 14:17 /dev/bus/usb/001/001
  crw-rw-r--  1 root root    189,   2 Feb 11 14:17 /dev/bus/usb/001/003
  crw-rw-r--  1 root root    189,   3 Feb 11 14:17 /dev/bus/usb/001/004
  crw-rw-r--  1 root plugdev 189,   4 Feb 14 12:23 /dev/bus/usb/001/005
  crw-rw-r--  1 root root    189,   5 Feb 11 14:17 /dev/bus/usb/001/006
  crw-rw----+ 1 root audio   189,  62 Feb 14 12:37 /dev/bus/usb/001/063
  crw-rw-r--  1 root root    189, 128 Feb 11 14:17 /dev/bus/usb/002/001
  crw-rw-r--  1 root root    189, 130 Feb 13 09:38 /dev/bus/usb/002/003
+ till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$
+ 
+ The printer is the device /dev/bus/usb/001/063:
+ 
+ till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ lsusb
+ Bus 002 Device 003: ID 0b95:1790 ASIX Electronics Corp. AX88179 Gigabit Ethernet
+ Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
+ Bus 001 Device 005: ID 138a:0097 Validity Sensors, Inc. 
+ Bus 001 Device 004: ID 04f2:b5ce Chicony Electronics Co., Ltd Integrated Camera
+ Bus 001 Device 003: ID 8087:0a2b Intel Corp. 
+ Bus 001 Device 006: ID 056a:50b7 Wacom Co., Ltd Pen and multitouch sensor
+ Bus 001 Device 063: ID 03f0:7a12 HP, Inc HP OfficeJet Pro 8730
+ Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ 
  
  There must be a bug somewhere in the UDEV rules.

** Also affects: systemd (Ubuntu)
   Importance: Undecided
       Status: New

** Changed in: systemd (Ubuntu)
   Importance: Undecided => High

** Also affects: pulseaudio (Ubuntu)
   Importance: Undecided
       Status: New

** Changed in: pulseaudio (Ubuntu)
   Importance: Undecided => High

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1863239

Title:
  /dev/bus/usb/*/* device file of HP multi-function printer assigned to
  "audio" group

Status in pulseaudio package in Ubuntu:
  New
Status in systemd package in Ubuntu:
  New
Status in udev package in Ubuntu:
  New

Bug description:
  When testing HPLIP I found out that CUPS backends can access my
  printer only when they are running as root, when they are running as
  the special user lp, as it is usually the case, they cannot access the
  printer.

  So I tried to find out why and saw that the /dev/bus/usb/*/* device
  file for the printer has group ownership "audio" and not "lp":

  till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ ll /dev/bus/usb/*/*
  crw-rw-r--  1 root root    189,   0 Feb 11 14:17 /dev/bus/usb/001/001
  crw-rw-r--  1 root root    189,   2 Feb 11 14:17 /dev/bus/usb/001/003
  crw-rw-r--  1 root root    189,   3 Feb 11 14:17 /dev/bus/usb/001/004
  crw-rw-r--  1 root plugdev 189,   4 Feb 14 12:23 /dev/bus/usb/001/005
  crw-rw-r--  1 root root    189,   5 Feb 11 14:17 /dev/bus/usb/001/006
  crw-rw----+ 1 root audio   189,  62 Feb 14 12:37 /dev/bus/usb/001/063
  crw-rw-r--  1 root root    189, 128 Feb 11 14:17 /dev/bus/usb/002/001
  crw-rw-r--  1 root root    189, 130 Feb 13 09:38 /dev/bus/usb/002/003
  till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$

  The printer is the device /dev/bus/usb/001/063:

  till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ lsusb
  Bus 002 Device 003: ID 0b95:1790 ASIX Electronics Corp. AX88179 Gigabit Ethernet
  Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
  Bus 001 Device 005: ID 138a:0097 Validity Sensors, Inc. 
  Bus 001 Device 004: ID 04f2:b5ce Chicony Electronics Co., Ltd Integrated Camera
  Bus 001 Device 003: ID 8087:0a2b Intel Corp. 
  Bus 001 Device 006: ID 056a:50b7 Wacom Co., Ltd Pen and multitouch sensor
  Bus 001 Device 063: ID 03f0:7a12 HP, Inc HP OfficeJet Pro 8730
  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  till at till-x1yoga:~/ubuntu/hplip/focal/debian/hplip-3.19.12+dfsg0$ 

  There must be a bug somewhere in the UDEV rules.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1863239/+subscriptions