linux/drivers/usb/core
Reilly Grant d883f52e1f usb: devio: Add ioctl to disallow detaching kernel USB drivers.
The new USBDEVFS_DROP_PRIVILEGES ioctl allows a process to voluntarily
relinquish the ability to issue other ioctls that may interfere with
other processes and drivers that have claimed an interface on the
device.

This commit also includes a simple utility to be able to test the
ioctl, located at Documentation/usb/usbdevfs-drop-permissions.c

Example (with qemu-kvm's input device):

    $ lsusb
    ...
    Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd

    $ usb-devices
    ...
    C:  #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=100mA
    I:  If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=02 Driver=usbhid

    $ sudo ./usbdevfs-drop-permissions /dev/bus/usb/001/002
    OK: privileges dropped!
    Available options:
    [0] Exit now
    [1] Reset device. Should fail if device is in use
    [2] Claim 4 interfaces. Should succeed where not in use
    [3] Narrow interface permission mask
    Which option shall I run?: 1
    ERROR: USBDEVFS_RESET failed! (1 - Operation not permitted)
    Which test shall I run next?: 2
    ERROR claiming if 0 (1 - Operation not permitted)
    ERROR claiming if 1 (1 - Operation not permitted)
    ERROR claiming if 2 (1 - Operation not permitted)
    ERROR claiming if 3 (1 - Operation not permitted)
    Which test shall I run next?: 0

After unbinding usbhid:

    $ usb-devices
    ...
    I:  If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=02 Driver=(none)

    $ sudo ./usbdevfs-drop-permissions /dev/bus/usb/001/002
    ...
    Which option shall I run?: 2
    OK: claimed if 0
    ERROR claiming if 1 (1 - Operation not permitted)
    ERROR claiming if 2 (1 - Operation not permitted)
    ERROR claiming if 3 (1 - Operation not permitted)
    Which test shall I run next?: 1
    OK: USBDEVFS_RESET succeeded
    Which test shall I run next?: 0

After unbinding usbhid and restricting the mask:

    $ sudo ./usbdevfs-drop-permissions /dev/bus/usb/001/002
    ...
    Which option shall I run?: 3
    Insert new mask: 0
    OK: privileges dropped!
    Which test shall I run next?: 2
    ERROR claiming if 0 (1 - Operation not permitted)
    ERROR claiming if 1 (1 - Operation not permitted)
    ERROR claiming if 2 (1 - Operation not permitted)
    ERROR claiming if 3 (1 - Operation not permitted)

Signed-off-by: Reilly Grant <reillyg@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Emilio López <emilio.lopez@collabora.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-05 12:05:01 -08:00
..
buffer.c usb: core: Allow compilation on platforms where NO_DMA=y 2016-02-20 20:22:55 -08:00
config.c usb: Add USB 3.1 Precision time measurement capability descriptor support 2016-02-14 17:03:23 -08:00
devices.c usb: core: rename mutex usb_bus_list_lock to usb_bus_idr_lock 2016-02-06 21:55:57 -08:00
devio.c usb: devio: Add ioctl to disallow detaching kernel USB drivers. 2016-03-05 12:05:01 -08:00
driver.c usb: core: driver: Use kmalloc_array 2015-10-04 10:47:19 +01:00
endpoint.c usb: endpoint: convert spaces to tabs 2015-08-14 16:50:36 -07:00
file.c usb: core: use kbasename() instead of open-coded variant 2016-01-24 20:37:47 -08:00
generic.c staging: usbip: convert usbip-host driver to usb_device_driver 2014-02-07 10:54:30 -08:00
hcd-pci.c usb: define USB_SPEED_SUPER_PLUS speed for SuperSpeedPlus USB3.1 devices 2016-01-24 20:16:52 -08:00
hcd.c usb: core: Allow compilation on platforms where NO_DMA=y 2016-02-20 20:22:55 -08:00
hub.c usb: hub: fix a typo in hub_port_init() leading to wrong logic 2016-03-03 19:44:06 -08:00
hub.h usb: Support USB 3.1 extended port status request 2016-01-24 20:16:52 -08:00
Kconfig usb: kconfig: fix warning of select USB_OTG 2015-11-19 16:31:42 -08:00
Makefile USB: core: remove CONFIG_USB_DEBUG usage 2013-12-21 16:01:00 -08:00
message.c usb: message: remove redundant declaration 2015-10-04 10:45:11 +01:00
notify.c usb: Add export.h for EXPORT_SYMBOL/THIS_MODULE where needed 2011-10-31 19:31:25 -04:00
otg_whitelist.h usb: otg_whitelist: remove whitespace 2015-08-14 16:50:36 -07:00
port.c More power management and ACPI updates for v4.5-rc1 2016-01-20 19:06:49 -08:00
quirks.c USB: add quirk for devices with broken LPM 2015-12-11 15:40:51 -08:00
sysfs.c usb: no locking for reading descriptors in sysfs 2016-02-03 13:29:12 -08:00
urb.c usb: define USB_SPEED_SUPER_PLUS speed for SuperSpeedPlus USB3.1 devices 2016-01-24 20:16:52 -08:00
usb-acpi.c usb: find internal hub tier mismatch via acpi 2014-05-27 16:38:52 -07:00
usb.c usb: core: switch bus numbering to using idr 2016-02-03 13:26:30 -08:00
usb.h usb: define USB_SPEED_SUPER_PLUS speed for SuperSpeedPlus USB3.1 devices 2016-01-24 20:16:52 -08:00