===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected syzkaller #0 Tainted: G L ----------------------------------------------------- syz.5.2921/13167 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff888075aaa2b8 (&new->fa_lock){...-}-{3:3}, at: kill_fasync_rcu fs/fcntl.c:1135 [inline] ffff888075aaa2b8 (&new->fa_lock){...-}-{3:3}, at: kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 and this task is already holding: ffff888071777028 (&client->buffer_lock){..-.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff888071777028 (&client->buffer_lock){..-.}-{3:3}, at: evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 which would create a new lock dependency: (&client->buffer_lock){..-.}-{3:3} -> (&new->fa_lock){...-}-{3:3} but this new dependency connects a SOFTIRQ-irq-safe lock: (&client->buffer_lock){..-.}-{3:3} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x117/0x340 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] evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 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/0x1e50 drivers/hid/hid-input.c:1747 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+0xe91/0x1720 drivers/hid/hid-core.c:2074 __hid_input_report drivers/hid/hid-core.c:2144 [inline] hid_input_report+0x44b/0x580 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/0x45b0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858 handle_softirqs+0x27d/0x850 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:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 check_kcov_mode kernel/kcov.c:183 [inline] write_comp_data kernel/kcov.c:246 [inline] __sanitizer_cov_trace_const_cmp8+0x31/0x90 kernel/kcov.c:321 _compound_head include/linux/page-flags.h:286 [inline] __folio_rmap_sanity_checks include/linux/rmap.h:417 [inline] __folio_add_rmap mm/rmap.c:1239 [inline] __folio_add_file_rmap mm/rmap.c:1585 [inline] folio_add_file_rmap_ptes+0x1d2/0xe60 mm/rmap.c:1611 set_pte_range+0x52e/0x8a0 mm/memory.c:5481 filemap_map_order0_folio mm/filemap.c:3856 [inline] filemap_map_pages+0xfcd/0x1fd0 mm/filemap.c:3921 do_fault_around mm/memory.c:5713 [inline] do_read_fault mm/memory.c:5746 [inline] do_fault mm/memory.c:5889 [inline] do_pte_missing+0x20b0/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{3:3} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x117/0x340 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:1672 do_wait+0x1e8/0x4f0 kernel/exit.c:1716 kernel_wait+0xab/0x170 kernel/exit.c:1892 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:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 other info that might help us debug this: Chain exists of: &client->buffer_lock --> &new->fa_lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&client->buffer_lock); lock(&new->fa_lock); lock(&client->buffer_lock); *** DEADLOCK *** 7 locks held by syz.5.2921/13167: #0: ffff888029dac118 (&evdev->mutex){+.+.}-{4:4}, at: evdev_write+0x1a1/0x480 drivers/input/evdev.c:511 #1: ffff88801d368230 (&dev->event_lock#2){..-.}-{3:3}, at: class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] #1: ffff88801d368230 (&dev->event_lock#2){..-.}-{3:3}, at: input_inject_event+0xa5/0x340 drivers/input/input.c:419 #2: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #2: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline] #2: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: input_inject_event+0xb6/0x340 drivers/input/input.c:420 #3: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #3: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #3: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline] #3: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: input_pass_values+0x8d/0x890 drivers/input/input.c:119 #4: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #4: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #4: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: evdev_events+0x79/0x340 drivers/input/evdev.c:298 #5: ffff888071777028 (&client->buffer_lock){..-.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #5: ffff888071777028 (&client->buffer_lock){..-.}-{3:3}, at: evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 #6: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #6: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #6: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: kill_fasync+0x53/0x4d0 fs/fcntl.c:1158 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&client->buffer_lock){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x117/0x340 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] evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 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/0x1e50 drivers/hid/hid-input.c:1747 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+0xe91/0x1720 drivers/hid/hid-core.c:2074 __hid_input_report drivers/hid/hid-core.c:2144 [inline] hid_input_report+0x44b/0x580 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/0x45b0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858 handle_softirqs+0x27d/0x850 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:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 check_kcov_mode kernel/kcov.c:183 [inline] write_comp_data kernel/kcov.c:246 [inline] __sanitizer_cov_trace_const_cmp8+0x31/0x90 kernel/kcov.c:321 _compound_head include/linux/page-flags.h:286 [inline] __folio_rmap_sanity_checks include/linux/rmap.h:417 [inline] __folio_add_rmap mm/rmap.c:1239 [inline] __folio_add_file_rmap mm/rmap.c:1585 [inline] folio_add_file_rmap_ptes+0x1d2/0xe60 mm/rmap.c:1611 set_pte_range+0x52e/0x8a0 mm/memory.c:5481 filemap_map_order0_folio mm/filemap.c:3856 [inline] filemap_map_pages+0xfcd/0x1fd0 mm/filemap.c:3921 do_fault_around mm/memory.c:5713 [inline] do_read_fault mm/memory.c:5746 [inline] do_fault mm/memory.c:5889 [inline] do_pte_missing+0x20b0/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 INITIAL USE at: lock_acquire+0x117/0x340 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] evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 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_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] evdev_open.__key.26+0x0/0x20 the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire+0x117/0x340 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:1672 do_wait+0x1e8/0x4f0 kernel/exit.c:1716 kernel_wait+0xab/0x170 kernel/exit.c:1892 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:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 SOFTIRQ-ON-R at: lock_acquire+0x117/0x340 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:1672 do_wait+0x1e8/0x4f0 kernel/exit.c:1716 kernel_wait+0xab/0x170 kernel/exit.c:1892 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:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INITIAL USE at: lock_acquire+0x117/0x340 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+0x2185/0x3950 kernel/fork.c:2367 kernel_clone+0x21e/0x820 kernel/fork.c:2651 user_mode_thread+0xdd/0x140 kernel/fork.c:2727 rest_init+0x23/0x300 init/main.c:722 start_kernel+0x3a7/0x400 init/main.c:1206 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+0x117/0x340 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:1672 do_wait+0x1e8/0x4f0 kernel/exit.c:1716 kernel_wait+0xab/0x170 kernel/exit.c:1892 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:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: __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:978 sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3669 queue_oob+0x420/0x4f0 net/unix/af_unix.c:2357 unix_stream_sendmsg+0xc32/0xde0 net/unix/af_unix.c:2491 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x52d/0x820 net/socket.c:2592 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646 __sys_sendmmsg+0x28e/0x430 net/socket.c:2728 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xa2/0xc0 net/compat.c:364 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x117/0x340 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+0x745/0x1a50 fs/fcntl.c:538 do_compat_fcntl64+0x477/0x720 fs/fcntl.c:800 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x117/0x340 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:918 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+0x180b/0x1ab0 fs/notify/fsnotify.c:641 fsnotify_name include/linux/fsnotify.h:55 [inline] fsnotify_dirent include/linux/fsnotify.h:61 [inline] fsnotify_create+0x122/0x180 include/linux/fsnotify.h:323 vfs_symlink+0x2c3/0x2d0 fs/namei.c:5516 do_symlinkat+0x1f5/0x3c0 fs/namei.c:5541 __do_sys_symlink fs/namei.c:5567 [inline] __se_sys_symlink fs/namei.c:5565 [inline] __ia32_sys_symlink+0x79/0x90 fs/namei.c:5565 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] file_f_owner_allocate.__key+0x0/0x20 ... acquired at: __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:918 kill_fasync_rcu fs/fcntl.c:1144 [inline] kill_fasync+0x24d/0x4d0 fs/fcntl.c:1159 lease_break_callback+0x26/0x30 fs/locks.c:558 __break_lease+0x730/0x1620 fs/locks.c:1598 break_lease include/linux/filelock.h:476 [inline] do_dentry_open+0x73a/0x1420 fs/open.c:953 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4628 [inline] path_openat+0x340e/0x3dd0 fs/namei.c:4787 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_compat_sys_open fs/open.c:1489 [inline] __se_compat_sys_open fs/open.c:1487 [inline] __ia32_compat_sys_open+0x117/0x140 fs/open.c:1487 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&new->fa_lock){...-}-{3:3} { IN-SOFTIRQ-R at: lock_acquire+0x117/0x340 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:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async_rcu include/net/sock.h:2570 [inline] sock_def_readable+0x3c1/0x530 net/core/sock.c:3613 tcp_data_queue+0x1e14/0x5e30 net/ipv4/tcp_input.c:5461 tcp_rcv_established+0xf57/0x2580 net/ipv4/tcp_input.c:6474 tcp_v4_do_rcv+0xa90/0x1430 net/ipv4/tcp_ipv4.c:1881 tcp_v4_rcv+0x2675/0x2f20 net/ipv4/tcp_ipv4.c:2324 ip_protocol_deliver_rcu+0x221/0x440 net/ipv4/ip_input.c:207 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6137 [inline] __netif_receive_skb+0x143/0x380 net/core/dev.c:6250 process_backlog+0x622/0x1500 net/core/dev.c:6602 __napi_poll+0xae/0x320 net/core/dev.c:7666 napi_poll net/core/dev.c:7729 [inline] net_rx_action+0x672/0xe50 net/core/dev.c:7881 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 do_softirq+0xec/0x180 kernel/softirq.c:523 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450 sk_stream_wait_memory+0x71f/0xf70 net/core/stream.c:149 tcp_sendmsg_locked+0x1dfb/0x5520 net/ipv4/tcp.c:1365 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1412 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:742 __sys_sendto+0x3bd/0x520 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __ia32_sys_sendto+0xdd/0x100 net/socket.c:2209 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL USE at: lock_acquire+0x117/0x340 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:1012 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:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] __do_fast_syscall_32+0x3cb/0x570 arch/x86/entry/syscall_32.c:310 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x117/0x340 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:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async_rcu include/net/sock.h:2570 [inline] sock_def_error_report+0x332/0x390 net/core/sock.c:3598 sk_error_report+0x48/0x270 net/core/sock.c:348 unix_dgram_disconnected net/unix/af_unix.c:630 [inline] unix_dgram_connect+0x96b/0xc20 net/unix/af_unix.c:1580 __sys_connect_file net/socket.c:2089 [inline] __sys_connect+0x316/0x440 net/socket.c:2108 __do_sys_connect net/socket.c:2114 [inline] __se_sys_connect net/socket.c:2111 [inline] __ia32_sys_connect+0x7a/0x90 net/socket.c:2111 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: __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:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x627/0xbd0 drivers/input/evdev.c:278 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 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_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e stack backtrace: CPU: 0 UID: 0 PID: 13167 Comm: syz.5.2921 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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 kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x2a95/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x340 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:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x627/0xbd0 drivers/input/evdev.c:278 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 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_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1f7/0x570 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf6ffd539 Code: 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 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:00000000f53ed55c EFLAGS: 00000206 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000040 RDX: 0000000000000037 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): 0: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 4: 10 07 adc %al,(%rdi) 6: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi a: 10 08 adc %cl,(%rax) c: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 ret 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 3e: 90 nop 3f: 90 nop