input: syz1 as /devices/virtual/input/input5 ====================================================== WARNING: possible circular locking dependency detected 6.1.148-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/3946 is trying to acquire lock: ffff888076fee070 (&newdev->mutex){+.+.}-{3:3}, at: uinput_request_send drivers/input/misc/uinput.c:150 [inline] ffff888076fee070 (&newdev->mutex){+.+.}-{3:3}, at: uinput_request_submit+0x198/0x700 drivers/input/misc/uinput.c:181 but task is already holding lock: ffff888076fed8b0 (&ff->mutex){+.+.}-{3:3}, at: input_ff_upload+0x397/0x9c0 drivers/input/ff-core.c:122 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ff->mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 input_ff_flush+0x5a/0x130 drivers/input/ff-core.c:242 input_flush_device+0x97/0xc0 drivers/input/input.c:682 evdev_release+0xe0/0x800 drivers/input/evdev.c:444 __fput+0x22c/0x920 fs/file_table.c:320 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #2 (&dev->mutex#2){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 input_register_handle+0x67/0x3a0 drivers/input/input.c:2629 kbd_connect+0xbf/0x130 drivers/tty/vt/keyboard.c:1589 input_attach_handler drivers/input/input.c:1060 [inline] input_register_device+0xd3e/0x10d0 drivers/input/input.c:2470 acpi_button_add+0x6b7/0xae0 drivers/acpi/button.c:570 acpi_device_probe+0xa3/0x300 drivers/acpi/bus.c:1023 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __driver_attach+0x44a/0x6e0 drivers/base/dd.c:1201 bus_for_each_dev+0x175/0x1e0 drivers/base/bus.c:303 bus_add_driver+0x30a/0x5a0 drivers/base/bus.c:620 driver_register+0x32d/0x430 drivers/base/driver.c:246 do_one_initcall+0x214/0x7a0 init/main.c:1298 do_initcall_level+0x137/0x1e4 init/main.c:1371 do_initcalls+0x4b/0x8a init/main.c:1387 kernel_init_freeable+0x3fa/0x5ac init/main.c:1626 kernel_init+0x19/0x1b0 init/main.c:1514 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 -> #1 (input_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 input_register_device+0xb08/0x10d0 drivers/input/input.c:2463 uinput_create_device+0x422/0x670 drivers/input/misc/uinput.c:364 uinput_ioctl_handler+0x7d8/0x14c0 drivers/input/misc/uinput.c:884 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&newdev->mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 uinput_request_send drivers/input/misc/uinput.c:150 [inline] uinput_request_submit+0x198/0x700 drivers/input/misc/uinput.c:181 uinput_dev_upload_effect+0x14d/0x1d0 drivers/input/misc/uinput.c:256 input_ff_upload+0x587/0x9c0 drivers/input/ff-core.c:152 evdev_do_ioctl drivers/input/evdev.c:1183 [inline] evdev_ioctl_handler+0x16f7/0x1de0 drivers/input/evdev.c:1272 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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.0/3946: #0: ffff888074d39110 (&evdev->mutex){+.+.}-{3:3}, at: evdev_ioctl_handler+0x122/0x1de0 drivers/input/evdev.c:1263 #1: ffff888076fed8b0 (&ff->mutex){+.+.}-{3:3}, at: input_ff_upload+0x397/0x9c0 drivers/input/ff-core.c:122 stack backtrace: CPU: 0 PID: 3946 Comm: syz-executor.0 Not tainted 6.1.148-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 uinput_request_send drivers/input/misc/uinput.c:150 [inline] uinput_request_submit+0x198/0x700 drivers/input/misc/uinput.c:181 uinput_dev_upload_effect+0x14d/0x1d0 drivers/input/misc/uinput.c:256 input_ff_upload+0x587/0x9c0 drivers/input/ff-core.c:152 evdev_do_ioctl drivers/input/evdev.c:1183 [inline] evdev_ioctl_handler+0x16f7/0x1de0 drivers/input/evdev.c:1272 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7bed47dca9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7bee29c0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f7bed5abf80 RCX: 00007f7bed47dca9 RDX: 0000000020000300 RSI: 0000000040304580 RDI: 0000000000000004 RBP: 00007f7bed4c947e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7bed5abf80 R15: 00007fffe58f1ef8