commit ff14dafde15c11403fac61367a34fea08926e9ee upstream.

To avoid racing with FF playback events and corrupting device's event
queue take event_lock spinlock when calling uinput_dev_event() when
submitting a FF upload or erase "event".

Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Link: https://patch.msgid.link/adXkf6MWzlB8LA_s@google.com
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 4cda78d6f8bf2b700529f2fbccb994c3e826d7c2 upstream.

A lockdep circular locking dependency warning can be triggered
reproducibly when using a force-feedback gamepad with uinput (for
example, playing ELDEN RING under Wine with a Flydigi Vader 5
controller):

  ff->mutex -> udev->mutex -> input_mutex -> dev->mutex -> ff->mutex

The cycle is caused by four lock acquisition paths:

1. ff upload: input_ff_upload() holds ff->mutex and calls
   uinput_dev_upload_effect() -> uinput_request_submit() ->
   uinput_request_send(), which acquires udev->mutex.

2. device create: uinput_ioctl_handler() holds udev->mutex and calls
   uinput_create_device() -> input_register_device(), which acquires
   input_mutex.

3. device register: input_register_device() holds input_mutex and
   calls kbd_connect() -> input_register_handle(), which acquires
   dev->mutex.

4. evdev release: evdev_release() calls input_flush_device() under
   dev->mutex, which calls input_ff_flush() acquiring ff->mutex.

Fix this by introducing a new state_lock spinlock to protect
udev->state and udev->dev access in uinput_request_send() instead of
acquiring udev->mutex.  The function only needs to atomically check
device state and queue an input event into the ring buffer via
uinput_dev_event() -- both operations are safe under a spinlock
(ktime_get_ts64() and wake_up_interruptible() do not sleep).  This
breaks the ff->mutex -> udev->mutex link since a spinlock is a leaf in
the lock ordering and cannot form cycles with mutexes.

To keep state transitions visible to uinput_request_send(), protect
writes to udev->state in uinput_create_device() and
uinput_destroy_device() with the same state_lock spinlock.

Additionally, move init_completion(&request->done) from
uinput_request_send() to uinput_request_submit() before
uinput_request_reserve_slot().  Once the slot is allocated,
uinput_flush_requests() may call complete() on it at any time from
the destroy path, so the completion must be initialised before the
request becomes visible.

Lock ordering after the fix:

  ff->mutex -> state_lock (spinlock, leaf)
  udev->mutex -> state_lock (spinlock, leaf)
  udev->mutex -> input_mutex -> dev->mutex -> ff->mutex (no back-edge)

Fixes: ff462551235d ("Input: uinput - switch to the new FF interface")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/CABXGCsMoxag+kEwHhb7KqhuyxfmGGd0P=tHZyb1uKE0pLr8Hkg@mail.gmail.com/
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Link: https://patch.msgid.link/20260407075031.38351-1-mikhail.v.gavrilov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit d3366a04770eea807f2826cbdb96934dd8c9bf79 upstream.

Struct ff_effect_compat is embedded twice inside
uinput_ff_upload_compat, contains internal padding. In particular, there
is a hole after struct ff_replay to satisfy alignment requirements for
the following union member. Without clearing the structure,
copy_to_user() may leak stack data to userspace.

Initialize ff_up_compat to zero before filling valid fields.

Fixes: 2d56f3a32c0e ("Input: refactor evdev 32bit compat to be shareable with uinput")
Cc: stable@vger.kernel.org
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
Link: https://lore.kernel.org/r/20250928063737.74590-1-zhen.ni@easystack.cn
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 206f533a0a7c683982af473079c4111f4a0f9f5e ]

From: Dmitry Torokhov <dmitry.torokhov@gmail.com>

When exercising uinput interface syzkaller may try setting up device
with a really large number of slots, which causes memory allocation
failure in input_mt_init_slots(). While this allocation failure is
handled properly and request is rejected, it results in syzkaller
reports. Additionally, such request may put undue burden on the
system which will try to free a lot of memory for a bogus request.

Fix it by limiting allowed number of slots to 100. This can easily
be extended if we see devices that can track more than 100 contacts.

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+0122fa359a69694395d5@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=0122fa359a69694395d5
Link: https://lore.kernel.org/r/Zqgi7NYEbpRsJfa2@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Going through all uses of timeval, I noticed that we screwed up
input_event in the previous attempts to fix it:

The time fields now match between kernel and user space, but all following
fields are in the wrong place.

Add the required padding that is implied by the glibc timeval definition
to fix the layout, and use a struct initializer to avoid leaking kernel
stack data.

Fixes: 141e5dcaa735 ("Input: input_event - fix the CONFIG_SPARC64 mixup")
Fixes: 2e746942ebac ("Input: input_event - provide override for sparc64")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20191213204936.3643476-2-arnd@arndb.de
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

uinput device is always available for writing so we should always report
EPOLLOUT and EPOLLWRNORM bits, not only when there is nothing to read from
the device.

Fixes: d4b675e1b527 ("Input: uinput - fix returning EPOLLOUT from uinput_poll")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20191209202254.GA107567@dtor-ws
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Always return EPOLLOUT from uinput_poll to allow polling /dev/uinput
for writable state.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Link: https://lore.kernel.org/r/20191204025014.5189-1-marcel@holtmann.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Pull input updates from Dmitry Torokhov:
 "Just a few small fixups and switching a couple of Thinkpads to SMBus
  for touchpads as PS/2 emulation is not working well"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: synaptics - enable SMBus on ThinkPad E480 and E580
  Input: imx_keypad - make sure keyboard can always wake up system
  Input: iqs5xx - get axis info before calling input_mt_init_slots()
  Input: uinput - add compat ioctl number translation for UI_*_FF_UPLOAD
  Input: silead - add MSSL0017 to acpi_device_id
  Input: elantech - enable middle button support on 2 ThinkPads
  Input: elan_i2c - increment wakeup count if wake source

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In the case of compat syscall ioctl numbers for UI_BEGIN_FF_UPLOAD and
UI_END_FF_UPLOAD need to be adjusted before being passed on
uinput_ioctl_handler() since code built with -m32 will be passing
slightly different values. Extend the code already covering
UI_SET_PHYS to cover UI_BEGIN_FF_UPLOAD and UI_END_FF_UPLOAD as well.

Reported-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>