Only use Mass Storage devices on a selected USB port - how?

Solution 1:

It seems to work for me in Ubuntu 14.04 with 2 flash keys & android phone as storage and usb network adapter & webcam as other type. (I couldn't test placing a usb hub)

1. Check USB port (which is a parent device for the plugged device)

   $ udevadm info --name=/dev/sdc --attribute-walk
   
     looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0':
       KERNELS=="2-1.2:1.0"
       SUBSYSTEMS=="usb"
       DRIVERS=="usb-storage"
       ATTRS{bInterfaceClass}=="08"
       ATTRS{bInterfaceSubClass}=="06"
       ATTRS{bInterfaceProtocol}=="50"
       ATTRS{bNumEndpoints}=="02"
       ATTRS{supports_autosuspend}=="1"
       ATTRS{bAlternateSetting}==" 0"
       ATTRS{bInterfaceNumber}=="00"
   

2. Create udev rule, matching usb port kernel name without usb-storage driver

   /etc/udev/rules.d/90-remove-non-storage.rules

   Allow any device that have storage as 1st interface (Composite devices allowed)

   KERNELS=="2-1.2:1.0", DRIVERS!="usb-storage", RUN+="/bin/sh -c 'echo 1 > /sys/bus/usb/drivers/hub/2-1\:1.0/port2/device/remove'"
   

   Block any device that have a non storage interface (Composite devices denied)

   Actually, Phone gets mounted as modem to /dev/ttyACM0 as KERNELS=="2-1.2:1.1". This will not let phones (composite devices) to be mount only simple storage devices will.

   KERNELS=="2-1.2:1.[0-9]*", DRIVERS!="usb-storage", RUN+="/bin/sh -c 'echo 1 > /sys/bus/usb/drivers/hub/2-1\:1.0/port2/device/remove'"
   

   Block only interfaces that are not storage (Composite devices allowed as storage only)

   After some search about a way to disable only non allowed interfaces. Driver unbinding seems to work. My phone could only be used as storage, It does not create /dev/ttyACM0.

   KERNELS=="2-1.2:1.[0-9]*", DRIVERS!="usb-storage", RUN+="/bin/sh -c 'echo -n %k >/sys%p/driver/unbind'"
   

3. Reload udev rules

   udevadm control --reload-rules
   

References:

• udev - Linux dynamic device management
• Chapter 13. Dynamic Kernel Device: Management with udev
• disable specific PCI device at boot
• Manual driver binding and unbinding
• sysfs descriptions & how to use