input: syz1 as /devices/virtual/input/input2 ====================================================== WARNING: possible circular locking dependency detected 6.1.134-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor240/4298 is trying to acquire lock: ffff0000d9ccf870 (&newdev->mutex){+.+.}-{3:3}, at: uinput_request_send drivers/input/misc/uinput.c:150 [inline] ffff0000d9ccf870 (&newdev->mutex){+.+.}-{3:3}, at: uinput_request_submit+0x188/0x654 drivers/input/misc/uinput.c:181 but task is already holding lock: ffff0000db3500b0 (&ff->mutex){+.+.}-{3:3}, at: input_ff_upload+0x31c/0x834 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+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 input_ff_upload+0x31c/0x834 drivers/input/ff-core.c:122 evdev_do_ioctl drivers/input/evdev.c:1183 [inline] evdev_ioctl_handler+0x1fd8/0x2d60 drivers/input/evdev.c:1272 evdev_ioctl+0x38/0x4c drivers/input/evdev.c:1281 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #2 (&evdev->mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 evdev_mark_dead drivers/input/evdev.c:1314 [inline] evdev_cleanup+0x38/0x16c drivers/input/evdev.c:1323 evdev_disconnect+0x58/0xc0 drivers/input/evdev.c:1407 __input_unregister_device+0x31c/0x5c0 drivers/input/input.c:2296 input_unregister_device+0xb0/0xfc drivers/input/input.c:2514 uinput_destroy_device+0x5a4/0x79c drivers/input/misc/uinput.c:298 uinput_release+0x44/0x60 drivers/input/misc/uinput.c:724 __fput+0x1c8/0x7c8 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x240/0x2f0 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x550/0x1a84 kernel/exit.c:871 do_group_exit+0x194/0x22c kernel/exit.c:1021 __do_sys_exit_group kernel/exit.c:1032 [inline] __se_sys_exit_group kernel/exit.c:1030 [inline] __wake_up_parent+0x0/0x60 kernel/exit.c:1030 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #1 (input_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_interruptible_nested+0x38/0x44 kernel/locking/mutex.c:821 input_register_device+0x914/0xf8c drivers/input/input.c:2463 uinput_create_device+0x360/0x528 drivers/input/misc/uinput.c:364 uinput_ioctl_handler+0x8b0/0x16c0 drivers/input/misc/uinput.c:884 uinput_ioctl+0x38/0x4c drivers/input/misc/uinput.c:1055 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #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+0x3338/0x7680 kernel/locking/lockdep.c:5049 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_interruptible_nested+0x38/0x44 kernel/locking/mutex.c:821 uinput_request_send drivers/input/misc/uinput.c:150 [inline] uinput_request_submit+0x188/0x654 drivers/input/misc/uinput.c:181 uinput_dev_upload_effect+0x170/0x218 drivers/input/misc/uinput.c:256 input_ff_upload+0x49c/0x834 drivers/input/ff-core.c:152 evdev_do_ioctl drivers/input/evdev.c:1183 [inline] evdev_ioctl_handler+0x1fd8/0x2d60 drivers/input/evdev.c:1272 evdev_ioctl+0x38/0x4c drivers/input/evdev.c:1281 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 other info that might help us debug this: Chain exists of: &newdev->mutex --> &evdev->mutex --> &ff->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ff->mutex); lock(&evdev->mutex); lock(&ff->mutex); lock(&newdev->mutex); *** DEADLOCK *** 2 locks held by syz-executor240/4298: #0: ffff0000c4be1110 (&evdev->mutex){+.+.}-{3:3}, at: evdev_ioctl_handler+0x11c/0x2d60 drivers/input/evdev.c:1263 #1: ffff0000db3500b0 (&ff->mutex){+.+.}-{3:3}, at: input_ff_upload+0x31c/0x834 drivers/input/ff-core.c:122 stack backtrace: CPU: 1 PID: 4298 Comm: syz-executor240 Not tainted 6.1.134-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x105c lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2048 check_noncircular+0x2cc/0x378 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+0x3338/0x7680 kernel/locking/lockdep.c:5049 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_interruptible_nested+0x38/0x44 kernel/locking/mutex.c:821 uinput_request_send drivers/input/misc/uinput.c:150 [inline] uinput_request_submit+0x188/0x654 drivers/input/misc/uinput.c:181 uinput_dev_upload_effect+0x170/0x218 drivers/input/misc/uinput.c:256 input_ff_upload+0x49c/0x834 drivers/input/ff-core.c:152 evdev_do_ioctl drivers/input/evdev.c:1183 [inline] evdev_ioctl_handler+0x1fd8/0x2d60 drivers/input/evdev.c:1272 evdev_ioctl+0x38/0x4c drivers/input/evdev.c:1281 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585