===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected syzkaller #0 Not tainted ----------------------------------------------------- syz.6.20470/20541 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff8880751f2a98 (&new->fa_lock){....}-{3:3}, at: kill_fasync_rcu fs/fcntl.c:1122 [inline] ffff8880751f2a98 (&new->fa_lock){....}-{3:3}, at: kill_fasync+0x199/0x4d0 fs/fcntl.c:1146 and this task is already holding: ffff888077da8468 (&tty->flow.lock){....}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] ffff888077da8468 (&tty->flow.lock){....}-{3:3}, at: start_tty+0x20/0x70 drivers/tty/tty_io.c:793 which would create a new lock dependency: (&tty->flow.lock){....}-{3:3} -> (&new->fa_lock){....}-{3:3} but this new dependency connects a SOFTIRQ-irq-safe lock: (kbd_event_lock){..-.}-{3:3} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __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+0xd2/0x3f70 drivers/tty/vt/keyboard.c:1528 input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2541 input_pass_values+0x288/0x890 drivers/input/input.c:128 input_event_dispose+0x3e5/0x6b0 drivers/input/input.c:353 input_event+0x89/0xe0 drivers/input/input.c:396 hidinput_hid_event+0x145e/0x1dd0 drivers/hid/hid-input.c:1730 hid_process_event+0x4be/0x620 drivers/hid/hid-core.c:1565 hid_process_report drivers/hid/hid-core.c:1713 [inline] hid_report_raw_event+0xe91/0x16d0 drivers/hid/hid-core.c:2074 __hid_input_report drivers/hid/hid-core.c:2144 [inline] hid_input_report+0x43e/0x520 drivers/hid/hid-core.c:2166 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1661 dummy_timer+0x85f/0x44c0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 variable_test_bit arch/x86/include/asm/bitops.h:222 [inline] arch_test_bit arch/x86/include/asm/bitops.h:233 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] cpumask_test_cpu include/linux/cpumask.h:646 [inline] cpu_online include/linux/cpumask.h:1205 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x58/0x360 kernel/locking/lockdep.c:5831 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 media_device_unregister_entity+0x4c/0x70 drivers/media/mc/mc-device.c:676 dvb_media_device_free+0x190/0x510 drivers/media/dvb-core/dvbdev.c:222 dvb_remove_device+0x107/0x280 drivers/media/dvb-core/dvbdev.c:607 dvb_unregister_device+0x18/0xa0 drivers/media/dvb-core/dvbdev.c:637 dvb_dmxdev_release+0x4d1/0x640 drivers/media/dvb-core/dmxdev.c:1471 dvb_usb_adapter_dvb_exit+0x9a/0x1b0 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:224 dvb_usb_adapter_exit+0x8b/0x240 drivers/media/usb/dvb-usb/dvb-usb-init.c:128 dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:143 [inline] dvb_usb_device_exit+0x1b6/0x350 drivers/media/usb/dvb-usb/dvb-usb-init.c:338 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:571 [inline] __device_release_driver drivers/base/dd.c:1274 [inline] device_release_driver_internal+0x4d9/0x800 drivers/base/dd.c:1297 bus_remove_device+0x34d/0x410 drivers/base/bus.c:579 device_del+0x511/0x8e0 drivers/base/core.c:3878 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1418 usb_disconnect+0x330/0x950 drivers/usb/core/hub.c:2344 hub_port_connect drivers/usb/core/hub.c:5406 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1667 do_wait+0x1f8/0x510 kernel/exit.c:1711 kernel_wait+0xab/0x170 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: kbd_event_lock --> &tty->flow.lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(kbd_event_lock); lock(&tty->flow.lock); lock(kbd_event_lock); *** DEADLOCK *** 6 locks held by syz.6.20470/20541: #0: ffff888077da80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffff888077da82e8 (&tty->termios_rwsem/1){++++}-{4:4}, at: tty_set_termios+0x138/0x17e0 drivers/tty/tty_ioctl.c:333 #2: ffff888077da80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x90 drivers/tty/tty_ldisc.c:263 #3: ffff888077da8468 (&tty->flow.lock){....}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] #3: ffff888077da8468 (&tty->flow.lock){....}-{3:3}, at: start_tty+0x20/0x70 drivers/tty/tty_io.c:793 #4: ffff888077da80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x90 drivers/tty/tty_ldisc.c:263 #5: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #5: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #5: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: kill_fasync+0x53/0x4d0 fs/fcntl.c:1145 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (kbd_event_lock){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __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+0xd2/0x3f70 drivers/tty/vt/keyboard.c:1528 input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2541 input_pass_values+0x288/0x890 drivers/input/input.c:128 input_event_dispose+0x3e5/0x6b0 drivers/input/input.c:353 input_event+0x89/0xe0 drivers/input/input.c:396 hidinput_hid_event+0x145e/0x1dd0 drivers/hid/hid-input.c:1730 hid_process_event+0x4be/0x620 drivers/hid/hid-core.c:1565 hid_process_report drivers/hid/hid-core.c:1713 [inline] hid_report_raw_event+0xe91/0x16d0 drivers/hid/hid-core.c:2074 __hid_input_report drivers/hid/hid-core.c:2144 [inline] hid_input_report+0x43e/0x520 drivers/hid/hid-core.c:2166 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1661 dummy_timer+0x85f/0x44c0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 variable_test_bit arch/x86/include/asm/bitops.h:222 [inline] arch_test_bit arch/x86/include/asm/bitops.h:233 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] cpumask_test_cpu include/linux/cpumask.h:646 [inline] cpu_online include/linux/cpumask.h:1205 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x58/0x360 kernel/locking/lockdep.c:5831 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 media_device_unregister_entity+0x4c/0x70 drivers/media/mc/mc-device.c:676 dvb_media_device_free+0x190/0x510 drivers/media/dvb-core/dvbdev.c:222 dvb_remove_device+0x107/0x280 drivers/media/dvb-core/dvbdev.c:607 dvb_unregister_device+0x18/0xa0 drivers/media/dvb-core/dvbdev.c:637 dvb_dmxdev_release+0x4d1/0x640 drivers/media/dvb-core/dmxdev.c:1471 dvb_usb_adapter_dvb_exit+0x9a/0x1b0 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:224 dvb_usb_adapter_exit+0x8b/0x240 drivers/media/usb/dvb-usb/dvb-usb-init.c:128 dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:143 [inline] dvb_usb_device_exit+0x1b6/0x350 drivers/media/usb/dvb-usb/dvb-usb-init.c:338 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:571 [inline] __device_release_driver drivers/base/dd.c:1274 [inline] device_release_driver_internal+0x4d9/0x800 drivers/base/dd.c:1297 bus_remove_device+0x34d/0x410 drivers/base/bus.c:579 device_del+0x511/0x8e0 drivers/base/core.c:3878 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1418 usb_disconnect+0x330/0x950 drivers/usb/core/hub.c:2344 hub_port_connect drivers/usb/core/hub.c:5406 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 vt_reset_unicode+0x2b/0x160 drivers/tty/vt/keyboard.c:2187 reset_vc+0x68/0x1b0 drivers/tty/vt/vt_ioctl.c:966 vc_init+0x70/0x4a0 drivers/tty/vt/vt.c:3728 con_init+0x385/0x9c0 drivers/tty/vt/vt.c:3793 console_init+0x10e/0x430 kernel/printk/printk.c:4298 start_kernel+0x254/0x410 init/main.c:1048 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147 } ... key at: [] kbd_event_lock+0x18/0xa0 keyboard.c:-1 -> (&tty->flow.lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] start_tty+0x20/0x70 drivers/tty/tty_io.c:793 n_tty_set_termios+0xa7c/0x1090 drivers/tty/n_tty.c:1858 tty_set_termios+0xda4/0x17e0 drivers/tty/tty_ioctl.c:348 set_termios+0x516/0x6c0 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x47e/0x740 drivers/tty/tty_ioctl.c:-1 tty_ioctl+0x9c6/0xde0 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] alloc_tty_struct.__key.35+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] stop_tty+0x2f/0x150 drivers/tty/tty_io.c:765 kbd_keycode drivers/tty/vt/keyboard.c:1515 [inline] kbd_event+0x2b72/0x3f70 drivers/tty/vt/keyboard.c:1534 input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2541 input_pass_values+0x288/0x890 drivers/input/input.c:128 input_event_dispose+0x330/0x6b0 drivers/input/input.c:342 input_inject_event+0x1dd/0x340 drivers/input/input.c:424 evdev_write+0x2fc/0x480 drivers/input/evdev.c:528 vfs_write+0x27e/0xb30 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/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+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1667 do_wait+0x1f8/0x510 kernel/exit.c:1711 kernel_wait+0xab/0x170 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1667 do_wait+0x1f8/0x510 kernel/exit.c:1711 kernel_wait+0xab/0x170 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 copy_process+0x224f/0x3c00 kernel/fork.c:2327 kernel_clone+0x21e/0x840 kernel/fork.c:2609 user_mode_thread+0xdd/0x140 kernel/fork.c:2685 rest_init+0x23/0x300 init/main.c:722 start_kernel+0x3ae/0x410 init/main.c:1111 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147 INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1667 do_wait+0x1f8/0x510 kernel/exit.c:1711 kernel_wait+0xab/0x170 kernel/exit.c:1887 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigurg+0x12b/0x420 fs/fcntl.c:965 sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3609 queue_oob+0x420/0x4f0 net/unix/af_unix.c:2380 unix_stream_sendmsg+0xc3f/0xdf0 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x52d/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmmsg+0x227/0x430 net/socket.c:2773 __do_sys_sendmmsg net/socket.c:2800 [inline] __se_sys_sendmmsg net/socket.c:2797 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2797 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/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+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 __f_setown+0x67/0x370 fs/fcntl.c:136 fcntl_dirnotify+0x3fa/0x6a0 fs/notify/dnotify/dnotify.c:369 do_fcntl+0x6d0/0x1910 fs/fcntl.c:537 __do_sys_fcntl fs/fcntl.c:589 [inline] __se_sys_fcntl+0xc8/0x150 fs/fcntl.c:574 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 send_sigio+0x38/0x370 fs/fcntl.c:905 dnotify_handle_event+0x169/0x440 fs/notify/dnotify/dnotify.c:113 fsnotify_handle_event fs/notify/fsnotify.c:376 [inline] send_to_group fs/notify/fsnotify.c:424 [inline] fsnotify+0x1814/0x1a80 fs/notify/fsnotify.c:641 fsnotify_parent include/linux/fsnotify.h:99 [inline] fsnotify_dentry include/linux/fsnotify.h:108 [inline] fsnotify_xattr include/linux/fsnotify.h:465 [inline] __vfs_setxattr_noperm+0x4f1/0x660 fs/xattr.c:237 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x274/0x600 fs/xattr.c:665 path_setxattrat+0x364/0x3a0 fs/xattr.c:713 __do_sys_lsetxattr fs/xattr.c:754 [inline] __se_sys_lsetxattr fs/xattr.c:750 [inline] __x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:750 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] file_f_owner_allocate.__key+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 send_sigio+0x38/0x370 fs/fcntl.c:905 kill_fasync_rcu fs/fcntl.c:1131 [inline] kill_fasync+0x24d/0x4d0 fs/fcntl.c:1146 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async_rcu include/net/sock.h:2547 [inline] sock_def_readable+0x3bb/0x550 net/core/sock.c:3553 queue_oob+0x452/0x4f0 net/unix/af_unix.c:2382 unix_stream_sendmsg+0xc3f/0xdf0 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x52d/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmmsg+0x227/0x430 net/socket.c:2773 __do_sys_sendmmsg net/socket.c:2800 [inline] __se_sys_sendmmsg net/socket.c:2797 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2797 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/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+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 fasync_remove_entry+0xf1/0x1c0 fs/fcntl.c:999 sock_fasync+0x85/0xf0 net/socket.c:1480 __fput+0x8a2/0xa70 fs/file_table.c:465 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 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+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1122 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1146 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async include/net/sock.h:2539 [inline] sk_send_sigurg+0x1f1/0x2e0 net/core/sock.c:3610 queue_oob+0x420/0x4f0 net/unix/af_unix.c:2380 unix_stream_sendmsg+0xc3f/0xdf0 net/unix/af_unix.c:2516 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x52d/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmmsg+0x227/0x430 net/socket.c:2773 __do_sys_sendmmsg net/socket.c:2800 [inline] __se_sys_sendmmsg net/socket.c:2797 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2797 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1122 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1146 tty_wakeup drivers/tty/tty_io.c:515 [inline] __start_tty+0x18c/0x220 drivers/tty/tty_io.c:777 start_tty+0x2b/0x70 drivers/tty/tty_io.c:794 n_tty_set_termios+0xa7c/0x1090 drivers/tty/n_tty.c:1858 tty_set_termios+0xda4/0x17e0 drivers/tty/tty_ioctl.c:348 set_termios+0x516/0x6c0 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x47e/0x740 drivers/tty/tty_ioctl.c:-1 tty_ioctl+0x9c6/0xde0 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 1 UID: 0 PID: 20541 Comm: syz.6.20470 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2616 [inline] check_irq_usage kernel/locking/lockdep.c:2857 [inline] check_prev_add kernel/locking/lockdep.c:3169 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0x1f05/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1122 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1146 tty_wakeup drivers/tty/tty_io.c:515 [inline] __start_tty+0x18c/0x220 drivers/tty/tty_io.c:777 start_tty+0x2b/0x70 drivers/tty/tty_io.c:794 n_tty_set_termios+0xa7c/0x1090 drivers/tty/n_tty.c:1858 tty_set_termios+0xda4/0x17e0 drivers/tty/tty_ioctl.c:348 set_termios+0x516/0x6c0 drivers/tty/tty_ioctl.c:516 tty_mode_ioctl+0x47e/0x740 drivers/tty/tty_ioctl.c:-1 tty_ioctl+0x9c6/0xde0 drivers/tty/tty_io.c:2801 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbcdb58f6c9 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:00007fbcdc3f3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbcdb7e6090 RCX: 00007fbcdb58f6c9 RDX: 0000200000000140 RSI: 0000000000005402 RDI: 0000000000000004 RBP: 00007fbcdb611f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fbcdb7e6128 R14: 00007fbcdb7e6090 R15: 00007fbcdb90fa28