===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected syzkaller #0 Not tainted ----------------------------------------------------- syz.1.3454/19376 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8e00c098 (tasklist_lock){.+.+}-{3:3}, at: send_sigurg+0xed/0xc80 fs/fcntl.c:965 and this task is already holding: ffff88807d9cbba0 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x5f/0xc80 fs/fcntl.c:949 which would create a new lock dependency: (&f_owner->lock){....}-{3:3} -> (tasklist_lock){.+.+}-{3:3} but this new dependency connects a SOFTIRQ-irq-safe lock: (&dev->event_lock#2){..-.}-{3:3} ... which became SOFTIRQ-irq-safe at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0x9f/0x3b0 drivers/input/input.c:419 __led_set_brightness drivers/leds/led-core.c:52 [inline] led_set_brightness_nopm drivers/leds/led-core.c:335 [inline] led_set_brightness_nosleep drivers/leds/led-core.c:369 [inline] led_set_brightness+0x217/0x290 drivers/leds/led-core.c:328 led_trigger_event drivers/leds/led-triggers.c:420 [inline] led_trigger_event+0xda/0x270 drivers/leds/led-triggers.c:408 kbd_propagate_led_state drivers/tty/vt/keyboard.c:1073 [inline] kbd_bh+0x21b/0x300 drivers/tty/vt/keyboard.c:1262 tasklet_action_common+0x284/0x400 kernel/softirq.c:925 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622 run_ksoftirqd kernel/softirq.c:1063 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:1055 smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{3:3} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1667 do_wait+0x21d/0x590 kernel/exit.c:1711 kernel_wait+0x9f/0x160 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: &dev->event_lock#2 --> &f_owner->lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock#2); lock(&f_owner->lock); lock(&dev->event_lock#2); *** DEADLOCK *** 2 locks held by syz.1.3454/19376: #0: ffff88807ca7f558 (&u->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #0: ffff88807ca7f558 (&u->lock){+.+.}-{3:3}, at: queue_oob net/unix/af_unix.c:2359 [inline] #0: ffff88807ca7f558 (&u->lock){+.+.}-{3:3}, at: unix_stream_sendmsg+0xd35/0x1340 net/unix/af_unix.c:2516 #1: ffff88807d9cbba0 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x5f/0xc80 fs/fcntl.c:949 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&dev->event_lock#2){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0x9f/0x3b0 drivers/input/input.c:419 __led_set_brightness drivers/leds/led-core.c:52 [inline] led_set_brightness_nopm drivers/leds/led-core.c:335 [inline] led_set_brightness_nosleep drivers/leds/led-core.c:369 [inline] led_set_brightness+0x217/0x290 drivers/leds/led-core.c:328 led_trigger_event drivers/leds/led-triggers.c:420 [inline] led_trigger_event+0xda/0x270 drivers/leds/led-triggers.c:408 kbd_propagate_led_state drivers/tty/vt/keyboard.c:1073 [inline] kbd_bh+0x21b/0x300 drivers/tty/vt/keyboard.c:1262 tasklet_action_common+0x284/0x400 kernel/softirq.c:925 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622 run_ksoftirqd kernel/softirq.c:1063 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:1055 smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0x9f/0x3b0 drivers/input/input.c:419 __led_set_brightness drivers/leds/led-core.c:52 [inline] led_set_brightness_nopm drivers/leds/led-core.c:335 [inline] led_set_brightness_nosleep drivers/leds/led-core.c:369 [inline] led_set_brightness+0x217/0x290 drivers/leds/led-core.c:328 kbd_led_trigger_activate+0xcb/0x110 drivers/tty/vt/keyboard.c:1029 led_trigger_set+0x59a/0xc50 drivers/leds/led-triggers.c:220 led_match_default_trigger drivers/leds/led-triggers.c:277 [inline] led_match_default_trigger drivers/leds/led-triggers.c:271 [inline] led_trigger_set_default drivers/leds/led-triggers.c:300 [inline] led_trigger_set_default+0x1e0/0x2e0 drivers/leds/led-triggers.c:284 led_classdev_register_ext+0x7b8/0xa10 drivers/leds/led-class.c:578 led_classdev_register include/linux/leds.h:274 [inline] input_leds_connect+0x552/0x8e0 drivers/input/input-leds.c:145 input_attach_handler.isra.0+0x176/0x250 drivers/input/input.c:994 input_register_device+0xab9/0x1180 drivers/input/input.c:2378 atkbd_connect+0x5f8/0xa40 drivers/input/keyboard/atkbd.c:1340 serio_connect_driver drivers/input/serio/serio.c:44 [inline] serio_driver_probe+0x7f/0xd0 drivers/input/serio/serio.c:748 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa90 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __driver_attach+0x283/0x580 drivers/base/dd.c:1217 bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:370 serio_attach_driver drivers/input/serio/serio.c:777 [inline] serio_handle_event+0x335/0xc30 drivers/input/serio/serio.c:214 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] __key.7+0x0/0x40 -> (kbd_event_lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 vt_reset_unicode+0x1e/0x130 drivers/tty/vt/keyboard.c:2187 reset_vc+0x77/0x280 drivers/tty/vt/vt_ioctl.c:966 vc_init+0x9e/0x490 drivers/tty/vt/vt.c:3728 con_init+0x2c2/0x700 drivers/tty/vt/vt.c:3793 console_init+0x152/0x680 kernel/printk/printk.c:4298 start_kernel+0x29f/0x4e0 init/main.c:1048 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 } ... key at: [] kbd_event_lock+0x18/0x60 keyboard.c:-1 ... acquired at: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] kbd_event+0x8a/0x1820 drivers/tty/vt/keyboard.c:1528 input_handle_events_default+0x119/0x1b0 drivers/input/input.c:2541 input_pass_values+0x74e/0x880 drivers/input/input.c:128 input_event_dispose drivers/input/input.c:342 [inline] input_handle_event+0xf00/0x14d0 drivers/input/input.c:370 input_inject_event+0x1e8/0x3b0 drivers/input/input.c:424 evdev_write+0x457/0x750 drivers/input/evdev.c:528 vfs_write+0x2a0/0x11d0 fs/read_write.c:684 ksys_write+0x1f8/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&tty->flow.lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] start_tty+0x21/0x190 drivers/tty/tty_io.c:793 n_tty_set_termios+0x713/0xf60 drivers/tty/n_tty.c:1858 tty_set_termios+0x6bd/0x980 drivers/tty/tty_ioctl.c:348 set_termios+0x5c6/0x880 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x57e/0xd30 drivers/tty/tty_ioctl.c:803 n_tty_ioctl_helper+0x4b/0x2b0 drivers/tty/tty_ioctl.c:982 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.4+0x0/0x40 ... acquired at: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] stop_tty+0x21/0x120 drivers/tty/tty_io.c:765 fn_hold+0xaf/0xd0 drivers/tty/vt/keyboard.c:527 k_spec drivers/tty/vt/keyboard.c:666 [inline] k_spec+0xf0/0x150 drivers/tty/vt/keyboard.c:655 kbd_keycode drivers/tty/vt/keyboard.c:1515 [inline] kbd_event+0xcd2/0x1820 drivers/tty/vt/keyboard.c:1534 input_handle_events_default+0x119/0x1b0 drivers/input/input.c:2541 input_pass_values+0x74e/0x880 drivers/input/input.c:128 input_event_dispose drivers/input/input.c:342 [inline] input_handle_event+0xf00/0x14d0 drivers/input/input.c:370 input_inject_event+0x1e8/0x3b0 drivers/input/input.c:424 evdev_write+0x457/0x750 drivers/input/evdev.c:528 vfs_write+0x2a0/0x11d0 fs/read_write.c:684 ksys_write+0x1f8/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&new->fa_lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 fasync_remove_entry+0xb2/0x1e0 fs/fcntl.c:999 fasync_helper+0xaf/0xd0 fs/fcntl.c:1102 snd_fasync_helper+0x1e2/0x290 sound/core/misc.c:141 __fput+0x96b/0xb70 fs/file_table.c:465 task_work_run+0x150/0x240 kernel/task_work.c:227 get_signal+0x1d0/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x426/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1122 [inline] kill_fasync fs/fcntl.c:1146 [inline] kill_fasync+0x138/0x510 fs/fcntl.c:1139 tty_wakeup+0xe8/0x120 drivers/tty/tty_io.c:515 __start_tty drivers/tty/tty_io.c:777 [inline] __start_tty drivers/tty/tty_io.c:770 [inline] start_tty+0x127/0x190 drivers/tty/tty_io.c:794 n_tty_set_termios+0x713/0xf60 drivers/tty/n_tty.c:1858 tty_set_termios+0x6bd/0x980 drivers/tty/tty_ioctl.c:348 set_termios+0x5c6/0x880 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x57e/0xd30 drivers/tty/tty_ioctl.c:803 n_tty_ioctl_helper+0x4b/0x2b0 drivers/tty/tty_ioctl.c:982 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.0+0x0/0x40 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1122 [inline] kill_fasync fs/fcntl.c:1146 [inline] kill_fasync+0x138/0x510 fs/fcntl.c:1139 tty_wakeup+0xe8/0x120 drivers/tty/tty_io.c:515 __start_tty drivers/tty/tty_io.c:777 [inline] __start_tty drivers/tty/tty_io.c:770 [inline] start_tty+0x127/0x190 drivers/tty/tty_io.c:794 n_tty_set_termios+0x713/0xf60 drivers/tty/n_tty.c:1858 tty_set_termios+0x6bd/0x980 drivers/tty/tty_ioctl.c:348 set_termios+0x5c6/0x880 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x57e/0xd30 drivers/tty/tty_ioctl.c:803 n_tty_ioctl_helper+0x4b/0x2b0 drivers/tty/tty_ioctl.c:982 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 __f_setown+0x61/0x3c0 fs/fcntl.c:136 generic_add_lease fs/locks.c:1874 [inline] generic_setlease fs/locks.c:1942 [inline] generic_setlease+0xef2/0x1300 fs/locks.c:1929 kernel_setlease+0x106/0x140 fs/locks.c:1991 vfs_setlease+0x258/0x2d0 fs/locks.c:2026 do_fcntl_add_lease fs/locks.c:2047 [inline] fcntl_setlease+0x3ed/0x5a0 fs/locks.c:2069 do_fcntl+0x751/0x15a0 fs/fcntl.c:534 __do_sys_fcntl fs/fcntl.c:589 [inline] __se_sys_fcntl fs/fcntl.c:574 [inline] __x64_sys_fcntl+0x163/0x200 fs/fcntl.c:574 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 send_sigio+0x31/0x3e0 fs/fcntl.c:905 kill_fasync_rcu fs/fcntl.c:1131 [inline] kill_fasync fs/fcntl.c:1146 [inline] kill_fasync+0x214/0x510 fs/fcntl.c:1139 tty_wakeup+0xe8/0x120 drivers/tty/tty_io.c:515 __start_tty drivers/tty/tty_io.c:777 [inline] __start_tty drivers/tty/tty_io.c:770 [inline] start_tty+0x127/0x190 drivers/tty/tty_io.c:794 n_tty_set_termios+0x713/0xf60 drivers/tty/n_tty.c:1858 tty_set_termios+0x6bd/0x980 drivers/tty/tty_ioctl.c:348 set_termios+0x5c6/0x880 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x57e/0xd30 drivers/tty/tty_ioctl.c:803 n_tty_ioctl_helper+0x4b/0x2b0 drivers/tty/tty_ioctl.c:982 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.1+0x0/0x40 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0x74/0x90 kernel/locking/spinlock.c:236 send_sigio+0x31/0x3e0 fs/fcntl.c:905 kill_fasync_rcu fs/fcntl.c:1131 [inline] kill_fasync fs/fcntl.c:1146 [inline] kill_fasync+0x214/0x510 fs/fcntl.c:1139 tty_wakeup+0xe8/0x120 drivers/tty/tty_io.c:515 __start_tty drivers/tty/tty_io.c:777 [inline] __start_tty drivers/tty/tty_io.c:770 [inline] start_tty+0x127/0x190 drivers/tty/tty_io.c:794 n_tty_set_termios+0x713/0xf60 drivers/tty/n_tty.c:1858 tty_set_termios+0x6bd/0x980 drivers/tty/tty_ioctl.c:348 set_termios+0x5c6/0x880 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x57e/0xd30 drivers/tty/tty_ioctl.c:803 n_tty_ioctl_helper+0x4b/0x2b0 drivers/tty/tty_ioctl.c:982 n_tty_ioctl+0x7f/0x370 drivers/tty/n_tty.c:2509 tty_ioctl+0x700/0x1680 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1667 do_wait+0x21d/0x590 kernel/exit.c:1711 kernel_wait+0x9f/0x160 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 SOFTIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1667 do_wait+0x21d/0x590 kernel/exit.c:1711 kernel_wait+0x9f/0x160 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0x36/0x50 kernel/locking/spinlock.c:326 copy_process+0x4fe3/0x76a0 kernel/fork.c:2327 kernel_clone+0xfc/0x930 kernel/fork.c:2609 user_mode_thread+0xc8/0x110 kernel/fork.c:2685 rest_init+0x23/0x2b0 init/main.c:722 start_kernel+0x3f6/0x4e0 init/main.c:1111 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 __do_wait+0x105/0x890 kernel/exit.c:1667 do_wait+0x21d/0x590 kernel/exit.c:1711 kernel_wait+0x9f/0x160 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xf1/0x170 kernel/umh.c:163 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 send_sigurg+0xed/0xc80 fs/fcntl.c:965 sk_send_sigurg+0x76/0x360 net/core/sock.c:3609 queue_oob net/unix/af_unix.c:2380 [inline] unix_stream_sendmsg+0xfa5/0x1340 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2630 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2684 __sys_sendmsg+0x16d/0x220 net/socket.c:2716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 0 UID: 0 PID: 19376 Comm: syz.1.3454 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2616 [inline] check_irq_usage+0x7dc/0x920 kernel/locking/lockdep.c:2857 check_prev_add kernel/locking/lockdep.c:3169 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1285/0x1c90 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x5f/0x70 kernel/locking/spinlock.c:228 send_sigurg+0xed/0xc80 fs/fcntl.c:965 sk_send_sigurg+0x76/0x360 net/core/sock.c:3609 queue_oob net/unix/af_unix.c:2380 [inline] unix_stream_sendmsg+0xfa5/0x1340 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2630 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2684 __sys_sendmsg+0x16d/0x220 net/socket.c:2716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffbbb58efc9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffbbc343038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ffbbb7e6180 RCX: 00007ffbbb58efc9 RDX: 0000000024004011 RSI: 0000200000002740 RDI: 0000000000000008 RBP: 00007ffbbb611f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffbbb7e6218 R14: 00007ffbbb7e6180 R15: 00007fffdb2f3e08 netlink: 16 bytes leftover after parsing attributes in process `syz.1.3454'.