netlink: 32 bytes leftover after parsing attributes in process `syz.4.950'. ===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 6.12.0-rc3-syzkaller-00217-g4d939780b705 #0 Not tainted ----------------------------------------------------- syz.4.950/10443 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8e60a058 (tasklist_lock){.+.+}-{2:2}, at: send_sigio+0x108/0x390 fs/fcntl.c:924 and this task is already holding: ffff88802cbc6a20 (&f_owner->lock){....}-{2:2}, at: send_sigio+0x37/0x390 fs/fcntl.c:910 which would create a new lock dependency: (&f_owner->lock){....}-{2:2} -> (tasklist_lock){.+.+}-{2:2} but this new dependency connects a SOFTIRQ-irq-safe lock: (&dev->event_lock#2){..-.}-{2:2} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 input_inject_event+0xc5/0x340 drivers/input/input.c:423 kd_sound_helper+0x1a0/0x210 drivers/tty/vt/keyboard.c:261 input_handler_for_each_handle+0x103/0x1d0 drivers/input/input.c:2676 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1794 expire_timers kernel/time/timer.c:1845 [inline] __run_timers kernel/time/timer.c:2419 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2430 run_timer_base kernel/time/timer.c:2439 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline] arch_local_irq_enable arch/x86/include/asm/irqflags.h:97 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1517 [inline] finish_lock_switch kernel/sched/core.c:5076 [inline] finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5194 context_switch kernel/sched/core.c:5325 [inline] __schedule+0x189d/0x4b30 kernel/sched/core.c:6682 schedule_idle+0x56/0x90 kernel/sched/core.c:6800 do_idle+0x56a/0x5d0 kernel/sched/idle.c:354 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424 rest_init+0x2dc/0x300 init/main.c:747 start_kernel+0x47f/0x500 init/main.c:1105 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{2:2} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0x12d/0x850 kernel/exit.c:1648 do_wait+0x1e9/0x560 kernel/exit.c:1692 kernel_wait+0xe9/0x240 kernel/exit.c:1868 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xbd/0x230 kernel/umh.c:164 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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 *** 6 locks held by syz.4.950/10443: #0: ffff88805d784420 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffffffff8eaa3f70 (file_rwsem){.+.+}-{0:0}, at: __break_lease+0x3b3/0x1820 fs/locks.c:1563 #2: ffff888030cda4e8 (&ctx->flc_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffff888030cda4e8 (&ctx->flc_lock){+.+.}-{2:2}, at: __break_lease+0x3c0/0x1820 fs/locks.c:1564 #3: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #3: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x54/0x4f0 fs/fcntl.c:1150 #4: ffff88806b2d30c0 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1127 [inline] #4: ffff88806b2d30c0 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x199/0x4f0 fs/fcntl.c:1151 #5: ffff88802cbc6a20 (&f_owner->lock){....}-{2:2}, at: send_sigio+0x37/0x390 fs/fcntl.c:910 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&dev->event_lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 input_inject_event+0xc5/0x340 drivers/input/input.c:423 kd_sound_helper+0x1a0/0x210 drivers/tty/vt/keyboard.c:261 input_handler_for_each_handle+0x103/0x1d0 drivers/input/input.c:2676 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1794 expire_timers kernel/time/timer.c:1845 [inline] __run_timers kernel/time/timer.c:2419 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2430 run_timer_base kernel/time/timer.c:2439 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline] arch_local_irq_enable arch/x86/include/asm/irqflags.h:97 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1517 [inline] finish_lock_switch kernel/sched/core.c:5076 [inline] finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5194 context_switch kernel/sched/core.c:5325 [inline] __schedule+0x189d/0x4b30 kernel/sched/core.c:6682 schedule_idle+0x56/0x90 kernel/sched/core.c:6800 do_idle+0x56a/0x5d0 kernel/sched/idle.c:354 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424 rest_init+0x2dc/0x300 init/main.c:747 start_kernel+0x47f/0x500 init/main.c:1105 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 input_inject_event+0xc5/0x340 drivers/input/input.c:423 kbd_led_trigger_activate+0xb8/0x100 drivers/tty/vt/keyboard.c:1036 led_trigger_set+0x582/0x9c0 drivers/leds/led-triggers.c:212 led_match_default_trigger drivers/leds/led-triggers.c:269 [inline] led_trigger_set_default+0x229/0x260 drivers/leds/led-triggers.c:287 led_classdev_register_ext+0x6e6/0x8a0 drivers/leds/led-class.c:555 led_classdev_register include/linux/leds.h:273 [inline] input_leds_connect+0x489/0x630 drivers/input/input-leds.c:145 input_attach_handler drivers/input/input.c:1027 [inline] input_register_device+0xd3b/0x1110 drivers/input/input.c:2470 atkbd_connect+0x752/0xa00 drivers/input/keyboard/atkbd.c:1340 serio_connect_driver drivers/input/serio/serio.c:44 [inline] serio_driver_probe+0x7f/0xa0 drivers/input/serio/serio.c:775 really_probe+0x2b8/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __driver_attach+0x45f/0x710 drivers/base/dd.c:1216 bus_for_each_dev+0x239/0x2b0 drivers/base/bus.c:370 serio_attach_driver drivers/input/serio/serio.c:804 [inline] serio_handle_event+0x1c7/0x920 drivers/input/serio/serio.c:224 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 } ... key at: [] input_allocate_device.__key.5+0x0/0x20 -> (&client->buffer_lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] evdev_fetch_next_event drivers/input/evdev.c:543 [inline] evdev_read+0x535/0xe00 drivers/input/evdev.c:584 do_loop_readv_writev fs/read_write.c:854 [inline] vfs_readv+0x6bc/0xa80 fs/read_write.c:1027 do_readv+0x1b1/0x350 fs/read_write.c:1087 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] evdev_open.__key.24+0x0/0x20 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __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] evdev_pass_values+0xf2/0xad0 drivers/input/evdev.c:261 evdev_events+0x1c2/0x300 drivers/input/evdev.c:306 input_pass_values+0x286/0x860 drivers/input/input.c:126 input_event_dispose+0x30f/0x600 drivers/input/input.c:341 input_handle_event+0xa71/0xbe0 drivers/input/input.c:369 input_inject_event+0x22f/0x340 drivers/input/input.c:428 evdev_write+0x5fd/0x790 drivers/input/evdev.c:528 vfs_write+0x29c/0xc90 fs/read_write.c:681 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&new->fa_lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:326 fasync_remove_entry+0xff/0x1d0 fs/fcntl.c:1004 sock_fasync+0x87/0x100 net/socket.c:1451 __fput+0x71b/0x880 fs/file_table.c:428 task_work_run+0x24f/0x310 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:939 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x16a3/0x1740 kernel/signal.c:2917 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 __do_fast_syscall_32+0xc4/0x110 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xdd/0x130 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1127 [inline] kill_fasync+0x199/0x4f0 fs/fcntl.c:1151 sock_wake_async+0x147/0x170 sk_wake_async+0x183/0x280 include/net/sock.h:2444 unix_release_sock+0x727/0xd00 net/unix/af_unix.c:710 unix_release+0x91/0xc0 net/unix/af_unix.c:1109 __sock_release net/socket.c:658 [inline] sock_close+0xbc/0x240 net/socket.c:1426 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 __do_fast_syscall_32+0xc4/0x110 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xdd/0x130 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1127 [inline] kill_fasync+0x199/0x4f0 fs/fcntl.c:1151 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x58a/0xad0 drivers/input/evdev.c:278 evdev_events+0x1c2/0x300 drivers/input/evdev.c:306 input_pass_values+0x286/0x860 drivers/input/input.c:126 input_event_dispose+0x30f/0x600 drivers/input/input.c:341 input_handle_event+0xa71/0xbe0 drivers/input/input.c:369 input_inject_event+0x22f/0x340 drivers/input/input.c:428 evdev_write+0x5fd/0x790 drivers/input/evdev.c:528 vfs_write+0x29c/0xc90 fs/read_write.c:681 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&f_owner->lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:326 __f_setown+0x6b/0x380 fs/fcntl.c:137 f_setown+0x243/0x310 fs/fcntl.c:184 do_fcntl+0x115/0x1a60 fs/fcntl.c:510 do_compat_fcntl64+0x572/0x1050 fs/fcntl.c:790 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock_irq include/linux/rwlock_api_smp.h:169 [inline] _raw_read_lock_irq+0xda/0x120 kernel/locking/spinlock.c:244 f_getown_ex fs/fcntl.c:271 [inline] do_fcntl+0x85f/0x1a60 fs/fcntl.c:513 do_compat_fcntl64+0x572/0x1050 fs/fcntl.c:790 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] file_f_owner_allocate.__key+0x0/0x20 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xdd/0x130 kernel/locking/spinlock.c:236 send_sigio+0x37/0x390 fs/fcntl.c:910 kill_fasync_rcu fs/fcntl.c:1136 [inline] kill_fasync+0x256/0x4f0 fs/fcntl.c:1151 sock_wake_async+0x147/0x170 sk_wake_async+0x183/0x280 include/net/sock.h:2444 unix_release_sock+0x727/0xd00 net/unix/af_unix.c:710 unix_release+0x91/0xc0 net/unix/af_unix.c:1109 __sock_release net/socket.c:658 [inline] sock_close+0xbc/0x240 net/socket.c:1426 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 __do_fast_syscall_32+0xc4/0x110 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{2:2} { HARDIRQ-ON-R at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0x12d/0x850 kernel/exit.c:1648 do_wait+0x1e9/0x560 kernel/exit.c:1692 kernel_wait+0xe9/0x240 kernel/exit.c:1868 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xbd/0x230 kernel/umh.c:164 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 SOFTIRQ-ON-R at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0x12d/0x850 kernel/exit.c:1648 do_wait+0x1e9/0x560 kernel/exit.c:1692 kernel_wait+0xe9/0x240 kernel/exit.c:1868 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xbd/0x230 kernel/umh.c:164 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:326 copy_process+0x2267/0x3d50 kernel/fork.c:2500 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 user_mode_thread+0x132/0x1a0 kernel/fork.c:2862 rest_init+0x23/0x300 init/main.c:712 start_kernel+0x47f/0x500 init/main.c:1105 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 INITIAL READ USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0x12d/0x850 kernel/exit.c:1648 do_wait+0x1e9/0x560 kernel/exit.c:1692 kernel_wait+0xe9/0x240 kernel/exit.c:1868 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xbd/0x230 kernel/umh.c:164 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigio+0x108/0x390 fs/fcntl.c:924 kill_fasync_rcu fs/fcntl.c:1136 [inline] kill_fasync+0x256/0x4f0 fs/fcntl.c:1151 lease_break_callback+0x26/0x30 fs/locks.c:558 __break_lease+0x6d5/0x1820 fs/locks.c:1592 vfs_truncate+0x26b/0x3b0 fs/open.c:105 do_sys_truncate+0xdb/0x190 fs/open.c:134 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e stack backtrace: CPU: 1 UID: 0 PID: 10443 Comm: syz.4.950 Not tainted 6.12.0-rc3-syzkaller-00217-g4d939780b705 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2647 [inline] check_irq_usage kernel/locking/lockdep.c:2888 [inline] check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x4ebd/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigio+0x108/0x390 fs/fcntl.c:924 kill_fasync_rcu fs/fcntl.c:1136 [inline] kill_fasync+0x256/0x4f0 fs/fcntl.c:1151 lease_break_callback+0x26/0x30 fs/locks.c:558 __break_lease+0x6d5/0x1820 fs/locks.c:1592 vfs_truncate+0x26b/0x3b0 fs/open.c:105 do_sys_truncate+0xdb/0x190 fs/open.c:134 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf742d579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f56f556c EFLAGS: 00000206 ORIG_RAX: 000000000000005c RAX: ffffffffffffffda RBX: 0000000020000040 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop