======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc4-next-20240418-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/14330 is trying to acquire lock:
ffff8880205a0870 (&newdev->mutex){+.+.}-{3:3}, at: uinput_request_send drivers/input/misc/uinput.c:151 [inline]
ffff8880205a0870 (&newdev->mutex){+.+.}-{3:3}, at: uinput_request_submit+0x19c/0x740 drivers/input/misc/uinput.c:182

but task is already holding lock:
ffff8880205a18b0 (&ff->mutex){+.+.}-{3:3}, at: input_ff_upload+0x3e4/0xb00 drivers/input/ff-core.c:120

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (
&ff->mutex
){+.+.}-{3:3}
:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       input_ff_flush+0x5e/0x140 drivers/input/ff-core.c:240
       input_flush_device+0x9c/0xc0 drivers/input/input.c:686
       evdev_release+0xf9/0x7d0 drivers/input/evdev.c:444
       __fput+0x406/0x8b0 fs/file_table.c:422
       __do_sys_close fs/open.c:1555 [inline]
       __se_sys_close fs/open.c:1540 [inline]
       __x64_sys_close+0x7f/0x110 fs/open.c:1540
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (
&dev->mutex
#2
){+.+.}-{3:3}
:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       input_disconnect_device drivers/input/input.c:761 [inline]
       __input_unregister_device+0x31/0x630 drivers/input/input.c:2217
       input_unregister_device+0xa3/0x100 drivers/input/input.c:2440
       uinput_destroy_device+0x6d1/0x8f0 drivers/input/misc/uinput.c:299
       uinput_ioctl_handler+0xb0c/0x1770 drivers/input/misc/uinput.c:908
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:907 [inline]
       __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0
 (
&newdev->mutex
){+.+.}-{3:3}
:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869
       __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       uinput_request_send drivers/input/misc/uinput.c:151 [inline]
       uinput_request_submit+0x19c/0x740 drivers/input/misc/uinput.c:182
       uinput_dev_upload_effect+0x199/0x240 drivers/input/misc/uinput.c:257
       input_ff_upload+0x5df/0xb00 drivers/input/ff-core.c:150
       evdev_do_ioctl drivers/input/evdev.c:1183 [inline]
       evdev_ioctl_handler+0x17d0/0x21b0 drivers/input/evdev.c:1272
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:907 [inline]
       __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  
&newdev->mutex
 --> &dev->mutex
#2
 --> &ff->mutex


 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(
&ff->mutex);
                               lock(&dev->mutex
#2);
                               lock(&ff->mutex
);
  lock(&newdev->mutex
);

 *** DEADLOCK ***

2 locks held by syz-executor.4/14330:
 #0: ffff88804cf8f110
 (&evdev->mutex
){+.+.}-{3:3}
, at: evdev_ioctl_handler+0x125/0x21b0 drivers/input/evdev.c:1263
 #1: ffff8880205a18b0
 (&ff->mutex
){+.+.}-{3:3}
, at: input_ff_upload+0x3e4/0xb00 drivers/input/ff-core.c:120

stack backtrace:
CPU: 0 PID: 14330 Comm: syz-executor.4 Tainted: G      D            6.9.0-rc4-next-20240418-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114