linux-stable.git/drivers/usb/core/driver.c, branch linux-5.10.y

usbcore: Check both id_table and match() when both available

2020-10-28T12:24:58+00:00

From: Bastien Nocera 

When a USB device driver has both an id_table and a match() function, make
sure to check both to find a match, first matching the id_table, then
checking the match() function.

This makes it possible to have module autoloading done through the
id_table when devices are plugged in, before checking for further
device eligibility in the match() function.

Cc:  # 5.8
Cc: Greg Kroah-Hartman 
Cc: Alan Stern 
Co-developed-by: M. Vefa Bicakci 
Tested-by: Bastien Nocera 
Signed-off-by: Bastien Nocera 
Signed-off-by: M. Vefa Bicakci 
Tested-by: Pan (Pany) YUAN 
Link: https://lore.kernel.org/r/20201022135521.375211-2-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman

Merge 5.9-rc8 into usb-next

2020-10-05T06:54:36+00:00

We need the USB fixes in here as well for testing.

Signed-off-by: Greg Kroah-Hartman

usbcore/driver: Accommodate usbip

2020-09-25T14:53:02+00:00

Commit 88b7381a939d ("USB: Select better matching USB drivers when
available") inadvertently broke usbip functionality. The commit in
question allows USB device drivers to be explicitly matched with
USB devices via the use of driver-provided identifier tables and
match functions, which is useful for a specialised device driver
to be chosen for a device that can also be handled by another,
more generic, device driver.

Prior, the USB device section of usb_device_match() had an
unconditional "return 1" statement, which allowed user-space to bind
USB devices to the usbip_host device driver, if desired. However,
the aforementioned commit changed the default/fallback return
value to zero. This breaks device drivers such as usbip_host, so
this commit restores the legacy behaviour, but only if a device
driver does not have an id_table and a match() function.

In addition, if usb_device_match is called for a device driver
and device pair where the device does not match the id_table of the
device driver in question, then the device driver will be disqualified
for the device. This allows avoiding the default case of "return 1",
which prevents undesirable probe() calls to a driver even though
its id_table did not match the device.

Finally, this commit changes the specialised-driver-to-generic-driver
transition code so that when a device driver returns -ENODEV, a more
generic device driver is only considered if the current device driver
does not have an id_table and a match() function. This ensures that
"generic" drivers such as usbip_host will not be considered specialised
device drivers and will not cause the device to be locked in to the
generic device driver, when a more specialised device driver could be
tried.

All of these changes restore usbip functionality without regressions,
ensure that the specialised/generic device driver selection logic works
as expected with the usb and apple-mfi-fastcharge drivers, and do not
negatively affect the use of devices provided by dummy_hcd.

Fixes: 88b7381a939d ("USB: Select better matching USB drivers when available")
Cc:  # 5.8
Cc: Bastien Nocera 
Cc: Valentina Manea 
Cc: Shuah Khan 
Cc: Greg Kroah-Hartman 
Cc: Alan Stern 
Cc: 
Tested-by: Andrey Konovalov 
Acked-by: Shuah Khan 
Signed-off-by: M. Vefa Bicakci 
Link: https://lore.kernel.org/r/20200922110703.720960-5-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman

usbcore/driver: Fix incorrect downcast

2020-09-25T14:53:02+00:00

This commit resolves a minor bug in the selection/discovery of more
specific USB device drivers for devices that are currently bound to
generic USB device drivers.

The bug is related to the way a candidate USB device driver is
compared against the generic USB device driver. The code in
is_dev_usb_generic_driver() assumes that the device driver in question
is a USB device driver by calling to_usb_device_driver(dev->driver)
to downcast; however I have observed that this assumption is not always
true, through code instrumentation.

This commit avoids the incorrect downcast altogether by comparing
the USB device's driver (i.e., dev->driver) to the generic USB
device driver directly. This method was suggested by Alan Stern.

This bug was found while investigating Andrey Konovalov's report
indicating usbip device driver misbehaviour with the recently merged
generic USB device driver selection feature. The report is linked
below.

Fixes: d5643d2249b2 ("USB: Fix device driver race")
Cc:  # 5.8
Cc: Greg Kroah-Hartman 
Cc: Alan Stern 
Cc: Bastien Nocera 
Cc: Shuah Khan 
Cc: Valentina Manea 
Cc: 
Tested-by: Andrey Konovalov 
Signed-off-by: M. Vefa Bicakci 
Link: https://lore.kernel.org/r/20200922110703.720960-4-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman

usbcore/driver: Fix specific driver selection

2020-09-25T14:52:49+00:00

This commit resolves a bug in the selection/discovery of more
specific USB device drivers for devices that are currently bound to
generic USB device drivers.

The bug is in the logic that determines whether a device currently
bound to a generic USB device driver should be re-probed by a
more specific USB device driver or not. The code in
__usb_bus_reprobe_drivers() used to have the following lines:

  if (usb_device_match_id(udev, new_udriver->id_table) == NULL &&
      (!new_udriver->match || new_udriver->match(udev) != 0))
 		return 0;

  ret = device_reprobe(dev);

As the reader will notice, the code checks whether the USB device in
consideration matches the identifier table (id_table) of a specific
USB device_driver (new_udriver), followed by a similar check, but this
time with the USB device driver's match function. However, the match
function's return value is not checked correctly. When match() returns
zero, it means that the specific USB device driver is *not* applicable
to the USB device in question, but the code then goes on to reprobe the
device with the new USB device driver under consideration. All this to
say, the logic is inverted.

This bug was found by code inspection and instrumentation while
investigating the root cause of the issue reported by Andrey Konovalov,
where usbip took over syzkaller's virtual USB devices in an undesired
manner. The report is linked below.

Fixes: d5643d2249b2 ("USB: Fix device driver race")
Cc:  # 5.8
Cc: Greg Kroah-Hartman 
Cc: Alan Stern 
Cc: Bastien Nocera 
Cc: Shuah Khan 
Cc: Valentina Manea 
Cc: 
Tested-by: Andrey Konovalov 
Signed-off-by: M. Vefa Bicakci 
Link: https://lore.kernel.org/r/20200922110703.720960-3-m.v.b@runbox.com
Signed-off-by: Greg Kroah-Hartman

usb: core: driver: fix stray tabs in error messages

2020-09-04T14:52:40+00:00

Commit 8bb54ab573ec ("usbcore: add usb_device_driver definition") added
the printk() calls with the error massages spoilt due to the stray tabs
in the middle. Remove these tabs and convert printk() calls to pr_err()
for consistency with the other code, while at it.

Fixes: 8bb54ab573ec ("usbcore: add usb_device_driver definition")
Signed-off-by: Sergey Shtylyov 
Acked-by: Alan Stern 
Link: https://lore.kernel.org/r/4beb55c4-eb34-7744-155f-033b8f527e23@omprussia.ru
Signed-off-by: Greg Kroah-Hartman

USB: Fix device driver race

2020-08-18T11:09:31+00:00

When a new device with a specialised device driver is plugged in, the
new driver will be modprobe()'d but the driver core will attach the
"generic" driver to the device.

After that, nothing will trigger a reprobe when the modprobe()'d device
driver has finished initialising, as the device has the "generic"
driver attached to it.

Trigger a reprobe ourselves when new specialised drivers get registered.

Fixes: 88b7381a939d ("USB: Select better matching USB drivers when available")
Signed-off-by: Bastien Nocera 
Cc: stable 
Acked-by: Alan Stern 
Link: https://lore.kernel.org/r/20200818110445.509668-3-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman

USB: Fallback to generic driver when specific driver fails

2020-02-12T19:01:55+00:00

If ->probe fails for a device specific driver, ask the driver core to
reprobe us, after having flagged the device for the generic driver to be
forced.

Signed-off-by: Bastien Nocera 
Acked-by: Alan Stern 
Link: https://lore.kernel.org/r/20191016093933.693-6-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman

USB: Select better matching USB drivers when available

2020-02-12T19:01:55+00:00

Now that USB device drivers can reuse code from the generic USB device
driver, we need to make sure that they get selected rather than the
generic driver. Add an id_table and match vfunc to the usb_device_driver
struct, which will get used to select a better matching driver at
->probe time.

This is a similar mechanism to that used in the HID drivers, with the
generic driver being selected unless there's a better matching one found
in the registered drivers (see hid_generic_match() in
drivers/hid/hid-generic.c).

Signed-off-by: Bastien Nocera 
Acked-by: Alan Stern 
Link: https://lore.kernel.org/r/20191016093933.693-5-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman

USB: Implement usb_device_match_id()

2020-02-12T19:01:55+00:00

Match a usb_device with a table of IDs.

Signed-off-by: Bastien Nocera 
Acked-by: Alan Stern 
Link: https://lore.kernel.org/r/20191016093933.693-4-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman