linux.git/drivers/usb/gadget, branch v4.9.67

usb: gadget: f_fs: Fix use-after-free in ffs_free_inst

2017-11-21T08:23:29+00:00

commit cdafb6d8b8da7fde266f79b3287ac221aa841879 upstream.

KASAN enabled configuration reports an error

BUG: KASAN: use-after-free in ffs_free_inst+... [usb_f_fs] at addr ...
Write of size 8 by task ...

This is observed after "ffs-test" is run and interrupted. If after that
functionfs is unmounted and g_ffs module is unloaded, that use-after-free
occurs during g_ffs module removal.

Although the report indicates ffs_free_inst() function, the actual
use-after-free condition occurs in _ffs_free_dev() function, which
is probably inlined into ffs_free_inst().

This happens due to keeping the ffs_data reference in device structure
during functionfs unmounting, while ffs_data itself is freed as no longer
needed. The fix is to clear that reference in ffs_closed() function,
which is a counterpart of ffs_ready(), where the reference is stored.

Fixes: 3262ad824307 ("usb: gadget: f_fs: Stop ffs_closed NULL pointer dereference")
Signed-off-by: Andrew Gabbasov 
Acked-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

usb: gadget: composite: Fix use-after-free in usb_composite_overwrite_options

2017-10-18T07:35:40+00:00

commit aec17e1e249567e82b26dafbb86de7d07fde8729 upstream.

KASAN enabled configuration reports an error

    BUG: KASAN: use-after-free in usb_composite_overwrite_options+...
                [libcomposite] at addr ...
    Read of size 1 by task ...

when some driver is un-bound and then bound again.
For example, this happens with FunctionFS driver when "ffs-test"
test application is run several times in a row.

If the driver has empty manufacturer ID string in initial static data,
it is then replaced with generated string. After driver unbinding
the generated string is freed, but the driver data still keep that
pointer. And if the driver is then bound again, that pointer
is re-used for string emptiness check.

The fix is to clean up the driver string data upon its unbinding
to drop the pointer to freed memory.

Fixes: cc2683c318a5 ("usb: gadget: Provide a default implementation of default manufacturer string")
Signed-off-by: Andrew Gabbasov 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb: gadget: configfs: Fix memory leak of interface directory data

2017-10-18T07:35:40+00:00

commit ff74745e6d3d97a865eda8c1f3fd29c13b79f0cc upstream.

Kmemleak checking configuration reports a memory leak in
usb_os_desc_prepare_interf_dir function when rndis function
instance is freed and then allocated again. For example, this
happens with FunctionFS driver with RNDIS function enabled
when "ffs-test" test application is run several times in a row.

The data for intermediate "os_desc" group for interface directories
is allocated as a single VLA chunk and (after a change of default
groups handling) is not ever freed and actually not stored anywhere
besides inside a list of default groups of a parent group.

The fix is to make usb_os_desc_prepare_interf_dir function return
a pointer to allocated data (as a pointer to the first VLA item)
instead of (an unused) integer and to make the caller component
(currently the only one is RNDIS function) responsible for storing
the pointer and freeing the memory when appropriate.

Fixes: 1ae1602de028 ("configfs: switch ->default groups to a linked list")
Signed-off-by: Andrew Gabbasov 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

USB: dummy-hcd: Fix deadlock caused by disconnect detection

2017-10-18T07:35:38+00:00

commit ab219221a5064abfff9f78c323c4a257b16cdb81 upstream.

The dummy-hcd driver calls the gadget driver's disconnect callback
under the wrong conditions.  It should invoke the callback when Vbus
power is turned off, but instead it does so when the D+ pullup is
turned off.

This can cause a deadlock in the composite core when a gadget driver
is unregistered:

[   88.361471] ============================================
[   88.362014] WARNING: possible recursive locking detected
[   88.362580] 4.14.0-rc2+ #9 Not tainted
[   88.363010] --------------------------------------------
[   88.363561] v4l_id/526 is trying to acquire lock:
[   88.364062]  (&(&cdev->lock)->rlock){....}, at: [] composite_disconnect+0x43/0x100 [libcomposite]
[   88.365051]
[   88.365051] but task is already holding lock:
[   88.365826]  (&(&cdev->lock)->rlock){....}, at: [] usb_function_deactivate+0x29/0x80 [libcomposite]
[   88.366858]
[   88.366858] other info that might help us debug this:
[   88.368301]  Possible unsafe locking scenario:
[   88.368301]
[   88.369304]        CPU0
[   88.369701]        ----
[   88.370101]   lock(&(&cdev->lock)->rlock);
[   88.370623]   lock(&(&cdev->lock)->rlock);
[   88.371145]
[   88.371145]  *** DEADLOCK ***
[   88.371145]
[   88.372211]  May be due to missing lock nesting notation
[   88.372211]
[   88.373191] 2 locks held by v4l_id/526:
[   88.373715]  #0:  (&(&cdev->lock)->rlock){....}, at: [] usb_function_deactivate+0x29/0x80 [libcomposite]
[   88.374814]  #1:  (&(&dum_hcd->dum->lock)->rlock){....}, at: [] dummy_pullup+0x7d/0xf0 [dummy_hcd]
[   88.376289]
[   88.376289] stack backtrace:
[   88.377726] CPU: 0 PID: 526 Comm: v4l_id Not tainted 4.14.0-rc2+ #9
[   88.378557] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   88.379504] Call Trace:
[   88.380019]  dump_stack+0x86/0xc7
[   88.380605]  __lock_acquire+0x841/0x1120
[   88.381252]  lock_acquire+0xd5/0x1c0
[   88.381865]  ? composite_disconnect+0x43/0x100 [libcomposite]
[   88.382668]  _raw_spin_lock_irqsave+0x40/0x54
[   88.383357]  ? composite_disconnect+0x43/0x100 [libcomposite]
[   88.384290]  composite_disconnect+0x43/0x100 [libcomposite]
[   88.385490]  set_link_state+0x2d4/0x3c0 [dummy_hcd]
[   88.386436]  dummy_pullup+0xa7/0xf0 [dummy_hcd]
[   88.387195]  usb_gadget_disconnect+0xd8/0x160 [udc_core]
[   88.387990]  usb_gadget_deactivate+0xd3/0x160 [udc_core]
[   88.388793]  usb_function_deactivate+0x64/0x80 [libcomposite]
[   88.389628]  uvc_function_disconnect+0x1e/0x40 [usb_f_uvc]

This patch changes the code to test the port-power status bit rather
than the port-connect status bit when deciding whether to isue the
callback.

Signed-off-by: Alan Stern 
Reported-by: David Tulloh 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

USB: g_mass_storage: Fix deadlock when driver is unbound

2017-10-12T09:51:17+00:00

commit 1fbbb78f25d1291274f320462bf6908906f538db upstream.

As a holdover from the old g_file_storage gadget, the g_mass_storage
legacy gadget driver attempts to unregister itself when its main
operating thread terminates (if it hasn't been unregistered already).
This is not strictly necessary; it was never more than an attempt to
have the gadget fail cleanly if something went wrong and the main
thread was killed.

However, now that the UDC core manages gadget drivers independently of
UDC drivers, this scheme doesn't work any more.  A simple test:

	modprobe dummy-hcd
	modprobe g-mass-storage file=...
	rmmod dummy-hcd

ends up in a deadlock with the following backtrace:

 sysrq: SysRq : Show Blocked State
   task                PC stack   pid father
 file-storage    D    0  1130      2 0x00000000
 Call Trace:
  __schedule+0x53e/0x58c
  schedule+0x6e/0x77
  schedule_preempt_disabled+0xd/0xf
  __mutex_lock.isra.1+0x129/0x224
  ? _raw_spin_unlock_irqrestore+0x12/0x14
  __mutex_lock_slowpath+0x12/0x14
  mutex_lock+0x28/0x2b
  usb_gadget_unregister_driver+0x29/0x9b [udc_core]
  usb_composite_unregister+0x10/0x12 [libcomposite]
  msg_cleanup+0x1d/0x20 [g_mass_storage]
  msg_thread_exits+0xd/0xdd7 [g_mass_storage]
  fsg_main_thread+0x1395/0x13d6 [usb_f_mass_storage]
  ? __schedule+0x573/0x58c
  kthread+0xd9/0xdb
  ? do_set_interface+0x25c/0x25c [usb_f_mass_storage]
  ? init_completion+0x1e/0x1e
  ret_from_fork+0x19/0x24
 rmmod           D    0  1155    683 0x00000000
 Call Trace:
  __schedule+0x53e/0x58c
  schedule+0x6e/0x77
  schedule_timeout+0x26/0xbc
  ? __schedule+0x573/0x58c
  do_wait_for_common+0xb3/0x128
  ? usleep_range+0x81/0x81
  ? wake_up_q+0x3f/0x3f
  wait_for_common+0x2e/0x45
  wait_for_completion+0x17/0x19
  fsg_common_put+0x34/0x81 [usb_f_mass_storage]
  fsg_free_inst+0x13/0x1e [usb_f_mass_storage]
  usb_put_function_instance+0x1a/0x25 [libcomposite]
  msg_unbind+0x2a/0x42 [g_mass_storage]
  __composite_unbind+0x4a/0x6f [libcomposite]
  composite_unbind+0x12/0x14 [libcomposite]
  usb_gadget_remove_driver+0x4f/0x77 [udc_core]
  usb_del_gadget_udc+0x52/0xcc [udc_core]
  dummy_udc_remove+0x27/0x2c [dummy_hcd]
  platform_drv_remove+0x1d/0x31
  device_release_driver_internal+0xe9/0x16d
  device_release_driver+0x11/0x13
  bus_remove_device+0xd2/0xe2
  device_del+0x19f/0x221
  ? selinux_capable+0x22/0x27
  platform_device_del+0x21/0x63
  platform_device_unregister+0x10/0x1a
  cleanup+0x20/0x817 [dummy_hcd]
  SyS_delete_module+0x10c/0x197
  ? ____fput+0xd/0xf
  ? task_work_run+0x55/0x62
  ? prepare_exit_to_usermode+0x65/0x75
  do_fast_syscall_32+0x86/0xc3
  entry_SYSENTER_32+0x4e/0x7c

What happens is that removing the dummy-hcd driver causes the UDC core
to unbind the gadget driver, which it does while holding the udc_lock
mutex.  The unbind routine in g_mass_storage tells the main thread to
exit and waits for it to terminate.

But as mentioned above, when the main thread exits it tries to
unregister the mass-storage function driver.  Via the composite
framework this ends up calling usb_gadget_unregister_driver(), which
tries to acquire the udc_lock mutex.  The result is deadlock.

The simplest way to fix the problem is not to be so clever: The main
thread doesn't have to unregister the function driver.  The side
effects won't be so terrible; if the gadget is still attached to a USB
host when the main thread is killed, it will appear to the host as
though the gadget's firmware has crashed -- a reasonably accurate
interpretation, and an all-too-common occurrence for USB mass-storage
devices.

In fact, the code to unregister the driver when the main thread exits
is specific to g-mass-storage; it is not used when f-mass-storage is
included as a function in a larger composite device.  Therefore the
entire mechanism responsible for this (the fsg_operations structure
with its ->thread_exits method, the fsg_common_set_ops() routine, and
the msg_thread_exits() callback routine) can all be eliminated.  Even
the msg_registered bitflag can be removed, because now the driver is
unregistered in only one place rather than in two places.

Signed-off-by: Alan Stern 
Acked-by: Felipe Balbi 
Acked-by: Michal Nazarewicz 
Signed-off-by: Greg Kroah-Hartman

usb: gadget: mass_storage: set msg_registered after msg registered

2017-10-12T09:51:17+00:00

commit 8e55d30322c6a0ef746c256a1beda9c73ecb27a6 upstream.

If there is no UDC available, the msg register will fail and this
flag will not be set, but the driver is already added into pending
driver list, then the module removal modprobe -r can not remove
the driver from the pending list.

Signed-off-by: Li Jun 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

USB: dummy-hcd: Fix erroneous synchronization change

2017-10-12T09:51:17+00:00

commit 7dbd8f4cabd96db5a50513de9d83a8105a5ffc81 upstream.

A recent change to the synchronization in dummy-hcd was incorrect.
The issue was that dummy_udc_stop() contained no locking and therefore
could race with various gadget driver callbacks, and the fix was to
add locking and issue the callbacks with the private spinlock held.

UDC drivers aren't supposed to do this.  Gadget driver callback
routines are allowed to invoke functions in the UDC driver, and these
functions will generally try to acquire the private spinlock.  This
would deadlock the driver.

The correct solution is to drop the spinlock before issuing callbacks,
and avoid races by emulating the synchronize_irq() call that all real
UDC drivers must perform in their ->udc_stop() routines after
disabling interrupts.  This involves adding a flag to dummy-hcd's
private structure to keep track of whether interrupts are supposed to
be enabled, and adding a counter to keep track of ongoing callbacks so
that dummy_udc_stop() can wait for them all to finish.

A real UDC driver won't receive disconnect, reset, suspend, resume, or
setup events once it has disabled interrupts.  dummy-hcd will receive
them but won't try to issue any gadget driver callbacks, which should
be just as good.

Signed-off-by: Alan Stern 
Fixes: f16443a034c7 ("USB: gadgetfs, dummy-hcd, net2280: fix locking for callbacks")
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

USB: dummy-hcd: fix infinite-loop resubmission bug

2017-10-12T09:51:16+00:00

commit 0173a68bfb0ad1c72a6ee39cc485aa2c97540b98 upstream.

The dummy-hcd HCD/UDC emulator tries not to do too much work during
each timer interrupt.  But it doesn't try very hard; currently all
it does is limit the total amount of bulk data transferred.  Other
transfer types aren't limited, and URBs that transfer no data (because
of an error, perhaps) don't count toward the limit, even though on a
real USB bus they would consume at least a minimum overhead.

This means it's possible to get the driver stuck in an infinite loop,
for example, if the host class driver resubmits an URB every time it
completes (which is common for interrupt URBs).  Each time the URB is
resubmitted it gets added to the end of the pending-URBs list, and
dummy-hcd doesn't stop until that list is empty.  Andrey Konovalov was
able to trigger this failure mode using the syzkaller fuzzer.

This patch fixes the infinite-loop problem by restricting the URBs
handled during each timer interrupt to those that were already on the
pending list when the interrupt routine started.  Newly added URBs
won't be processed until the next timer interrupt.  The problem of
properly accounting for non-bulk bandwidth (as well as packet and
transaction overhead) is not addressed here.

Signed-off-by: Alan Stern 
Reported-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

USB: dummy-hcd: fix connection failures (wrong speed)

2017-10-12T09:51:16+00:00

commit fe659bcc9b173bcfdd958ce2aec75e47651e74e1 upstream.

The dummy-hcd UDC driver is not careful about the way it handles
connection speeds.  It ignores the module parameter that is supposed
to govern the maximum connection speed and it doesn't set the HCD
flags properly for the case where it ends up running at full speed.

The result is that in many cases, gadget enumeration over dummy-hcd
fails because the bMaxPacketSize byte in the device descriptor is set
incorrectly.  For example, the default settings call for a high-speed
connection, but the maxpacket value for ep0 ends up being set for a
Super-Speed connection.

This patch fixes the problem by initializing the gadget's max_speed
and the HCD flags correctly.

Signed-off-by: Alan Stern 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb: gadget: udc: renesas_usb3: Fix return value of usb3_write_pipe()

2017-10-12T09:51:15+00:00

commit 447b8a01b84f048d93d43bfe1fcaa4fcc56595cc upstream.

This patch fixes an issue that this driver cannot go status stage
in control read when the req.zero is set to 1 and the len in
usb3_write_pipe() is set to 0. Otherwise, if we use g_ncm driver,
usb enumeration takes long time (5 seconds or more).

Fixes: 746bfe63bba3 ("usb: gadget: renesas_usb3: add support for Renesas USB3.0 peripheral controller")
Signed-off-by: Yoshihiro Shimoda 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman