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

usb: core: sysfs: Unmerge @usb3_hardware_lpm_attr_group in remove_power_attributes()

2024-09-04T11:17:47+00:00

commit 3a8839bbb86da7968a792123ed2296d063871a52 upstream.

Device attribute group @usb3_hardware_lpm_attr_group is merged by
add_power_attributes(), but it is not unmerged explicitly, fixed by
unmerging it in remove_power_attributes().

Fixes: 655fe4effe0f ("usbcore: add sysfs support to xHCI usb3 hardware LPM")
Cc: stable@vger.kernel.org
Signed-off-by: Zijun Hu 
Link: https://lore.kernel.org/r/20240820-sysfs_fix-v2-1-a9441487077e@quicinc.com
Signed-off-by: Greg Kroah-Hartman

USB: core: Fix deadlock in usb_deauthorize_interface()

2024-04-13T10:59:14+00:00

commit 80ba43e9f799cbdd83842fc27db667289b3150f5 upstream.

Among the attribute file callback routines in
drivers/usb/core/sysfs.c, the interface_authorized_store() function is
the only one which acquires a device lock on an ancestor device: It
calls usb_deauthorize_interface(), which locks the interface's parent
USB device.

The will lead to deadlock if another process already owns that lock
and tries to remove the interface, whether through a configuration
change or because the device has been disconnected.  As part of the
removal procedure, device_del() waits for all ongoing sysfs attribute
callbacks to complete.  But usb_deauthorize_interface() can't complete
until the device lock has been released, and the lock won't be
released until the removal has finished.

The mechanism provided by sysfs to prevent this kind of deadlock is
to use the sysfs_break_active_protection() function, which tells sysfs
not to wait for the attribute callback.

Reported-and-tested by: Yue Sun 
Reported by: xingwei lee 

Signed-off-by: Alan Stern 
Link: https://lore.kernel.org/linux-usb/CAEkJfYO6jRVC8Tfrd_R=cjO0hguhrV31fDPrLrNOOHocDkPoAA@mail.gmail.com/#r
Fixes: 310d2b4124c0 ("usb: interface authorization: SysFS part of USB interface authorization")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1c37eea1-9f56-4534-b9d8-b443438dc869@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman

driver core: Move the "removable" attribute from USB to core

2023-12-08T07:46:15+00:00

[ Upstream commit 70f400d4d957c2453c8689552ff212bc59f88938 ]

Move the "removable" attribute from USB to core in order to allow it to be
supported by other subsystem / buses. Individual buses that want to support
this attribute can populate the removable property of the device while
enumerating it with the 3 possible values -
 - "unknown"
 - "fixed"
 - "removable"
Leaving the field unchanged (i.e. "not supported") would mean that the
attribute would not show up in sysfs for that device. The UAPI (location,
symantics etc) for the attribute remains unchanged.

Move the "removable" attribute from USB to the device core so it can be
used by other subsystems / buses.

By default, devices do not have a "removable" attribute in sysfs.

If a subsystem or bus driver wants to support a "removable" attribute, it
should call device_set_removable() before calling device_register() or
device_add(), e.g.:

    device_set_removable(dev, DEVICE_REMOVABLE);
    device_register(dev);

The possible values and the resulting sysfs attribute contents are:

    DEVICE_REMOVABLE_UNKNOWN  ->  "unknown"
    DEVICE_REMOVABLE          ->  "removable"
    DEVICE_FIXED              ->  "fixed"

Convert the USB "removable" attribute to use this new device core
functionality.  There should be no user-visible change in the location or
semantics of attribute for USB devices.

Reviewed-by: Bjorn Helgaas 
Signed-off-by: Rajat Jain 
Link: https://lore.kernel.org/r/20210524171812.18095-1-rajatja@google.com
Signed-off-by: Greg Kroah-Hartman 
Stable-dep-of: 432e664e7c98 ("drm/amdgpu: don't use ATRM for external devices")
Signed-off-by: Sasha Levin

USB: core: Don't hold device lock while reading the "descriptors" sysfs file

2023-03-03T10:44:52+00:00

commit 45bf39f8df7f05efb83b302c65ae3b9bc92b7065 upstream.

Ever since commit 83e83ecb79a8 ("usb: core: get config and string
descriptors for unauthorized devices") was merged in 2013, there has
been no mechanism for reallocating the rawdescriptors buffers in
struct usb_device after the initial enumeration.  Before that commit,
the buffers would be deallocated when a device was deauthorized and
reallocated when it was authorized and enumerated.

This means that the locking in the read_descriptors() routine is not
needed, since the buffers it reads will never be reallocated while the
routine is running.  This locking can interfere with user programs
trying to read a hub's descriptors via sysfs while new child devices
of the hub are being initialized, since the hub is locked during this
procedure.

Since the locking in read_descriptors() hasn't been needed for over
nine years, we can remove it.

Reported-and-tested-by: Troels Liebe Bentsen 
Signed-off-by: Alan Stern 
CC: stable@vger.kernel.org
Link: https://lore.kernel.org/r/Y9l+wDTRbuZABzsE@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman

usb: core: fix slab-out-of-bounds Read in read_descriptors

2020-09-04T14:41:22+00:00

The USB device descriptor may get changed between two consecutive
enumerations on the same device for some reason, such as DFU or
malicius device.
In that case, we may access the changing descriptor if we don't take
the device lock here.

The issue is reported:
https://syzkaller.appspot.com/bug?id=901a0d9e6519ef8dc7acab25344bd287dd3c7be9

Cc: stable 
Cc: Alan Stern 
Reported-by: syzbot+256e56ddde8b8957eabd@syzkaller.appspotmail.com
Fixes: 217a9081d8e6 ("USB: add all configs to the "descriptors" attribute")
Signed-off-by: Zeng Tao 
Link: https://lore.kernel.org/r/1599201467-11000-1-git-send-email-prime.zeng@hisilicon.com
Signed-off-by: Greg Kroah-Hartman

USB: core: Replace an empty statement with a debug message

2020-04-23T13:28:13+00:00

This patch adds a dev_dbg() message to usb_create_sysfs_intf_files().
The message is not expected ever to appear; it's real purpose is to
satisfy the __must_check attribute on device_create_file() without
triggering a compiler warning about an empty statement.

In fact we don't really care if the sysfs attribute file doesn't get
created.  The interface string descriptor is purely informational and
hardly ever present.

Suggested-by: NeilBrown 
Signed-off-by: Alan Stern 

Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221618500.11262-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman

usb: use kobj_to_dev() API

2020-02-14T16:38:15+00:00

Use kobj_to_dev() API instead of container_of().

Signed-off-by: chenqiwu 
Link: https://lore.kernel.org/r/1581683820-9978-1-git-send-email-qiwuchen55@gmail.com
Signed-off-by: Greg Kroah-Hartman

usb: setup authorized_default attributes using usb_bus_notify

2019-08-08T14:07:34+00:00

Currently, the authorized_default and interface_authorized_default
attributes for HCD are set up after the uevent has been sent to userland.
This creates a race condition where userland may fail to access this
file when processing the event. Move the appending of these attributes
earlier relying on the usb_bus_notify dispatcher.

Signed-off-by: Thiébaud Weksteen 
Cc: stable 
Link: https://lore.kernel.org/r/20190806110050.38918-1-tweek@google.com
Signed-off-by: Greg Kroah-Hartman

USB: Add new USB LPM helpers

2019-01-18T09:02:56+00:00

Use new helpers to make LPM enabling/disabling more clear.

This is a preparation to subsequent patch.

Signed-off-by: Kai-Heng Feng 
Cc: stable  # after much soaking
Signed-off-by: Greg Kroah-Hartman

USB: USB 3.2 Add sysfs entries for a usb device rx_lanes and tx_lanes

2018-04-22T14:19:26+00:00

Add rx_lanes and tx_lanes lane count sysfs entries for a usb device
struct usb_devuce rx_lanes and tx_lanes variables.

Shows number of lanes used by the usb device

Data rate of a device is the lane speed * lane count, for example
USB 3.2 Gen 2x2 device uses 10Gbps signaling per lane, and has dual-lane
support 10Gbps * 2 = 20Gbps

Signed-off-by: Mathias Nyman 
Signed-off-by: Greg Kroah-Hartman