linux-stable.git/drivers/usb/core, branch v4.4.192

USB: core: Fix races in character device registration and deregistraion

2019-08-25T08:53:01+00:00

commit 303911cfc5b95d33687d9046133ff184cf5043ff upstream.

The syzbot fuzzer has found two (!) races in the USB character device
registration and deregistration routines.  This patch fixes the races.

The first race results from the fact that usb_deregister_dev() sets
usb_minors[intf->minor] to NULL before calling device_destroy() on the
class device.  This leaves a window during which another thread can
allocate the same minor number but will encounter a duplicate name
error when it tries to register its own class device.  A typical error
message in the system log would look like:

    sysfs: cannot create duplicate filename '/class/usbmisc/ldusb0'

The patch fixes this race by destroying the class device first.

The second race is in usb_register_dev().  When that routine runs, it
first allocates a minor number, then drops minor_rwsem, and then
creates the class device.  If the device creation fails, the minor
number is deallocated and the whole routine returns an error.  But
during the time while minor_rwsem was dropped, there is a window in
which the minor number is allocated and so another thread can
successfully open the device file.  Typically this results in
use-after-free errors or invalid accesses when the other thread closes
its open file reference, because the kernel then tries to release
resources that were already deallocated when usb_register_dev()
failed.  The patch fixes this race by keeping minor_rwsem locked
throughout the entire routine.

Reported-and-tested-by: syzbot+30cf45ebfe0b0c4847a1@syzkaller.appspotmail.com
Signed-off-by: Alan Stern 
CC: 
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.1908121607590.1659-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman

usb: core: hub: Disable hub-initiated U1/U2

2019-08-04T07:34:56+00:00

[ Upstream commit 561759292774707b71ee61aecc07724905bb7ef1 ]

If the device rejects the control transfer to enable device-initiated
U1/U2 entry, then the device will not initiate U1/U2 transition. To
improve the performance, the downstream port should not initate
transition to U1/U2 to avoid the delay from the device link command
response (no packet can be transmitted while waiting for a response from
the device). If the device has some quirks and does not implement U1/U2,
it may reject all the link state change requests, and the downstream
port may resend and flood the bus with more requests. This will affect
the device performance even further. This patch disables the
hub-initated U1/U2 if the device-initiated U1/U2 entry fails.

Reference: USB 3.2 spec 7.2.4.2.3

Signed-off-by: Thinh Nguyen 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

usb: Handle USB3 remote wakeup for LPM enabled devices correctly

2019-08-04T07:34:53+00:00

commit e244c4699f859cf7149b0781b1894c7996a8a1df upstream.

With Link Power Management (LPM) enabled USB3 links transition to low
power U1/U2 link states from U0 state automatically.

Current hub code detects USB3 remote wakeups by checking if the software
state still shows suspended, but the link has transitioned from suspended
U3 to enabled U0 state.

As it takes some time before the hub thread reads the port link state
after a USB3 wake notification, the link may have transitioned from U0
to U1/U2, and wake is not detected by hub code.

Fix this by handling U1/U2 states in the same way as U0 in USB3 wakeup
handling

This patch should be added to stable kernels since 4.13 where LPM was
kept enabled during suspend/resume

Cc:  # v4.13+
Signed-off-by: Lee, Chiasheng 
Signed-off-by: Mathias Nyman 
Signed-off-by: Greg Kroah-Hartman

USB: Fix chipmunk-like voice when using Logitech C270 for recording audio.

2019-06-22T06:18:24+00:00

commit bd21f0222adab64974b7d1b4b8c7ce6b23e9ea4d upstream.

This patch fixes the chipmunk-like voice that manifets randomly when
using the integrated mic of the Logitech Webcam HD C270.

The issue was solved initially for this device by commit 2394d67e446b
("USB: add RESET_RESUME for webcams shown to be quirky") but it was then
reintroduced by e387ef5c47dd ("usb: Add USB_QUIRK_RESET_RESUME for all
Logitech UVC webcams"). This patch is to have the fix back.

Signed-off-by: Marco Zatta 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

USB: Add LPM quirk for Surface Dock GigE adapter

2019-06-11T10:24:08+00:00

commit ea261113385ac0a71c2838185f39e8452d54b152 upstream.

Without USB_QUIRK_NO_LPM ethernet will not work and rtl8152 will
complain with

    r8152 : Stop submitting intr, status -71

Adding the quirk resolves this. As the dock is externally powered, this
should not have any drawbacks.

Signed-off-by: Maximilian Luz 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

USB: Fix slab-out-of-bounds write in usb_get_bos_descriptor

2019-06-11T10:24:08+00:00

commit a03ff54460817c76105f81f3aa8ef655759ccc9a upstream.

The syzkaller USB fuzzer found a slab-out-of-bounds write bug in the
USB core, caused by a failure to check the actual size of a BOS
descriptor.  This patch adds a check to make sure the descriptor is at
least as large as it is supposed to be, so that the code doesn't
inadvertently access memory beyond the end of the allocated region
when assigning to dev->bos->desc->bNumDeviceCaps later on.

Signed-off-by: Alan Stern 
Reported-and-tested-by: syzbot+71f1e64501a309fcc012@syzkaller.appspotmail.com
CC: 
Signed-off-by: Greg Kroah-Hartman

usb: core: Add PM runtime calls to usb_hcd_platform_shutdown

2019-06-11T10:24:05+00:00

[ Upstream commit 8ead7e817224d7832fe51a19783cb8fcadc79467 ]

If ohci-platform is runtime suspended, we can currently get an "imprecise
external abort" on reboot with ohci-platform loaded when PM runtime
is implemented for the SoC.

Let's fix this by adding PM runtime support to usb_hcd_platform_shutdown.

Signed-off-by: Tony Lindgren 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

USB: core: Don't unbind interfaces following device reset failure

2019-06-11T10:23:58+00:00

[ Upstream commit 381419fa720060ba48b7bbc483be787d5b1dca6f ]

The SCSI core does not like to have devices or hosts unregistered
while error recovery is in progress.  Trying to do so can lead to
self-deadlock: Part of the removal code tries to obtain a lock already
held by the error handler.

This can cause problems for the usb-storage and uas drivers, because
their error handler routines perform a USB reset, and if the reset
fails then the USB core automatically goes on to unbind all drivers
from the device's interfaces -- all while still in the context of the
SCSI error handler.

As it turns out, practically all the scenarios leading to a USB reset
failure end up causing a device disconnect (the main error pathway in
usb_reset_and_verify_device(), at the end of the routine, calls
hub_port_logical_disconnect() before returning).  As a result, the
hub_wq thread will soon become aware of the problem and will unbind
all the device's drivers in its own context, not in the
error-handler's context.

This means that usb_reset_device() does not need to call
usb_unbind_and_rebind_marked_interfaces() in cases where
usb_reset_and_verify_device() has returned an error, because hub_wq
will take care of everything anyway.

This particular problem was observed in somewhat artificial
circumstances, by using usbfs to tell a hub to power-down a port
connected to a USB-3 mass storage device using the UAS protocol.  With
the port turned off, the currently executing command timed out and the
error handler started running.  The USB reset naturally failed,
because the hub port was off, and the error handler deadlocked as
described above.  Not carrying out the call to
usb_unbind_and_rebind_marked_interfaces() fixes this issue.

Signed-off-by: Alan Stern 
Reported-by: Kento Kobayashi 
Tested-by: Kento Kobayashi 
CC: Bart Van Assche 
CC: Martin K. Petersen 
CC: Jacky Cao 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

USB: core: Fix bug caused by duplicate interface PM usage counter

2019-05-16T17:45:00+00:00

commit c2b71462d294cf517a0bc6e4fd6424d7cee5596f upstream.

The syzkaller fuzzer reported a bug in the USB hub driver which turned
out to be caused by a negative runtime-PM usage counter.  This allowed
a hub to be runtime suspended at a time when the driver did not expect
it.  The symptom is a WARNING issued because the hub's status URB is
submitted while it is already active:

	URB 0000000031fb463e submitted while active
	WARNING: CPU: 0 PID: 2917 at drivers/usb/core/urb.c:363

The negative runtime-PM usage count was caused by an unfortunate
design decision made when runtime PM was first implemented for USB.
At that time, USB class drivers were allowed to unbind from their
interfaces without balancing the usage counter (i.e., leaving it with
a positive count).  The core code would take care of setting the
counter back to 0 before allowing another driver to bind to the
interface.

Later on when runtime PM was implemented for the entire kernel, the
opposite decision was made: Drivers were required to balance their
runtime-PM get and put calls.  In order to maintain backward
compatibility, however, the USB subsystem adapted to the new
implementation by keeping an independent usage counter for each
interface and using it to automatically adjust the normal usage
counter back to 0 whenever a driver was unbound.

This approach involves duplicating information, but what is worse, it
doesn't work properly in cases where a USB class driver delays
decrementing the usage counter until after the driver's disconnect()
routine has returned and the counter has been adjusted back to 0.
Doing so would cause the usage counter to become negative.  There's
even a warning about this in the USB power management documentation!

As it happens, this is exactly what the hub driver does.  The
kick_hub_wq() routine increments the runtime-PM usage counter, and the
corresponding decrement is carried out by hub_event() in the context
of the hub_wq work-queue thread.  This work routine may sometimes run
after the driver has been unbound from its interface, and when it does
it causes the usage counter to go negative.

It is not possible for hub_disconnect() to wait for a pending
hub_event() call to finish, because hub_disconnect() is called with
the device lock held and hub_event() acquires that lock.  The only
feasible fix is to reverse the original design decision: remove the
duplicate interface-specific usage counter and require USB drivers to
balance their runtime PM gets and puts.  As far as I know, all
existing drivers currently do this.

Signed-off-by: Alan Stern 
Reported-and-tested-by: syzbot+7634edaea4d0b341c625@syzkaller.appspotmail.com
CC: 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

USB: core: Fix unterminated string returned by usb_string()

2019-05-16T17:45:00+00:00

commit c01c348ecdc66085e44912c97368809612231520 upstream.

Some drivers (such as the vub300 MMC driver) expect usb_string() to
return a properly NUL-terminated string, even when an error occurs.
(In fact, vub300's probe routine doesn't bother to check the return
code from usb_string().)  When the driver goes on to use an
unterminated string, it leads to kernel errors such as
stack-out-of-bounds, as found by the syzkaller USB fuzzer.

An out-of-range string index argument is not at all unlikely, given
that some devices don't provide string descriptors and therefore list
0 as the value for their string indexes.  This patch makes
usb_string() return a properly terminated empty string along with the
-EINVAL error code when an out-of-range index is encountered.

And since a USB string index is a single-byte value, indexes >= 256
are just as invalid as values of 0 or below.

Signed-off-by: Alan Stern 
Reported-by: syzbot+b75b85111c10b8d680f1@syzkaller.appspotmail.com
CC: 
Signed-off-by: Greg Kroah-Hartman