===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 6.18.0-rc7-next-20251126 #1 Not tainted ----------------------------------------------------- syz-executor.4/123522 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff88801be3d020 (&f_owner->lock){....}-{3:3}, at: send_sigio+0x31/0x370 and this task is already holding: ffff88804724a2b8 (&new->fa_lock){....}-{3:3}, at: kill_fasync+0x137/0x520 which would create a new lock dependency: (&new->fa_lock){....}-{3:3} -> (&f_owner->lock){....}-{3:3} but this new dependency connects a SOFTIRQ-irq-safe lock: (&dev->event_lock){..-.}-{3:3} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 led_trigger_event+0xda/0x270 kbd_bh+0x23a/0x310 tasklet_action_common+0x270/0x730 handle_softirqs+0x1b1/0x740 run_ksoftirqd+0x2e/0x60 smpboot_thread_fn+0x41d/0x9d0 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{3:3} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 other info that might help us debug this: Chain exists of: &dev->event_lock --> &new->fa_lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock); lock(&new->fa_lock); lock(&dev->event_lock); *** DEADLOCK *** 4 locks held by syz-executor.4/123522: #0: ffff888048240d88 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 #1: ffffffff85e1ff60 (rcu_read_lock){....}-{1:3}, at: unix_release_sock+0xaba/0x1320 #2: ffffffff85e1ff60 (rcu_read_lock){....}-{1:3}, at: kill_fasync+0x61/0x520 #3: ffff88804724a2b8 (&new->fa_lock){....}-{3:3}, at: kill_fasync+0x137/0x520 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&dev->event_lock){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 netlink: 'syz-executor.0': attribute type 16 has an invalid length. input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 led_trigger_event+0xda/0x270 kbd_bh+0x23a/0x310 tasklet_action_common+0x270/0x730 handle_softirqs+0x1b1/0x740 run_ksoftirqd+0x2e/0x60 smpboot_thread_fn+0x41d/0x9d0 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_spin_lock_irqsave+0x3a/0x60 input_inject_event+0x9f/0x3b0 led_set_brightness+0x215/0x290 kbd_led_trigger_activate+0xcd/0x110 led_trigger_set+0x4cc/0xaa0 led_trigger_set_default+0x1e7/0x2e0 led_classdev_register_ext+0x615/0x950 input_leds_connect+0x49b/0x870 input_attach_handler+0x17a/0x260 input_register_device+0x9ff/0x1050 atkbd_connect+0x5e6/0xa10 serio_driver_probe+0x84/0xe0 really_probe+0x240/0x820 __driver_probe_device+0x2c4/0x380 driver_probe_device+0x4e/0x2a0 __driver_attach+0x1b0/0x590 bus_for_each_dev+0x12b/0x1c0 serio_handle_event+0x23b/0xaa0 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 } ... key at: [] __key.4+0x0/0x40 -> (&client->buffer_lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_spin_lock+0x2b/0x40 evdev_pass_values.part.0+0xf6/0x940 evdev_events+0x3b5/0x430 input_pass_values+0x708/0x860 input_handle_event+0xdcf/0x13d0 input_inject_event+0x1e5/0x3b0 evdev_write+0x2e1/0x420 vfs_write+0x2b7/0x1150 ksys_write+0x1ef/0x240 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.93+0x0/0x40 ... acquired at: _raw_spin_lock+0x2b/0x40 evdev_pass_values.part.0+0xf6/0x940 evdev_events+0x3b5/0x430 input_pass_values+0x708/0x860 input_handle_event+0xdcf/0x13d0 input_inject_event+0x1e5/0x3b0 evdev_write+0x2e1/0x420 vfs_write+0x2b7/0x1150 ksys_write+0x1ef/0x240 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&new->fa_lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_write_lock_irq+0x33/0x50 fasync_remove_entry+0xb2/0x1e0 fasync_helper+0xa6/0xc0 sock_fasync+0x92/0x140 __fput+0x94b/0xb50 fput_close_sync+0x10f/0x230 __x64_sys_close+0x8f/0x120 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x75/0x90 kill_fasync+0x137/0x520 evdev_pass_values.part.0+0x665/0x940 evdev_events+0x3b5/0x430 input_pass_values+0x708/0x860 input_handle_event+0xdcf/0x13d0 input_inject_event+0x1e5/0x3b0 evdev_write+0x2e1/0x420 vfs_write+0x2b7/0x1150 ksys_write+0x1ef/0x240 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.0+0x0/0x40 ... acquired at: _raw_read_lock_irqsave+0x75/0x90 kill_fasync+0x137/0x520 evdev_pass_values.part.0+0x665/0x940 evdev_events+0x3b5/0x430 input_pass_values+0x708/0x860 input_handle_event+0xdcf/0x13d0 input_inject_event+0x1e5/0x3b0 evdev_write+0x2e1/0x420 vfs_write+0x2b7/0x1150 ksys_write+0x1ef/0x240 do_syscall_64+0xbf/0x420 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+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 SOFTIRQ-ON-R at: lock_acquire+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_write_lock_irq+0x33/0x50 copy_process+0x4e71/0x7230 kernel_clone+0xea/0x7c0 user_mode_thread+0xc8/0x110 rest_init+0x24/0x290 start_kernel+0x3fa/0x510 x86_64_start_reservations+0x18/0x30 x86_64_start_kernel+0x109/0x120 common_startup_64+0x13e/0x148 INITIAL READ USE at: lock_acquire+0x15e/0x2d0 _raw_read_lock+0x5c/0x70 __do_wait+0x13e/0x8f0 do_wait+0x19f/0x530 kernel_wait+0x9f/0x160 call_usermodehelper_exec_work+0xf9/0x180 process_one_work+0x8e1/0x1960 worker_thread+0x67e/0xe90 kthread+0x3c8/0x740 ret_from_fork+0x67a/0x7a0 ret_from_fork_asm+0x1a/0x30 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: _raw_read_lock+0x5c/0x70 send_sigurg+0xef/0xc90 sk_send_sigurg+0x76/0x360 unix_stream_sendmsg+0xfce/0x1360 ____sys_sendmsg+0xa34/0xbf0 ___sys_sendmsg+0x10f/0x1b0 __sys_sendmsg+0x150/0x200 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x15e/0x2d0 _raw_write_lock_irq+0x33/0x50 __f_setown+0x60/0x3c0 generic_setlease+0xfb4/0x16e0 kernel_setlease+0x10c/0x130 vfs_setlease+0x1f1/0x290 do_fcntl_add_lease+0x3b0/0x540 fcntl_setlease+0xfa/0x180 do_fcntl+0x4e3/0x1500 __x64_sys_fcntl+0x155/0x1f0 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x75/0x90 send_sigurg+0x60/0xc90 sk_send_sigurg+0x76/0x360 unix_stream_sendmsg+0xfce/0x1360 ____sys_sendmsg+0xa34/0xbf0 ___sys_sendmsg+0x10f/0x1b0 __sys_sendmsg+0x150/0x200 do_syscall_64+0xbf/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.1+0x0/0x40 ... acquired at: lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x75/0x90 send_sigio+0x31/0x370 kill_fasync+0x218/0x520 sock_wake_async+0xd6/0x160 unix_release_sock+0xb60/0x1320 unix_release+0x91/0xf0 __sock_release+0xb3/0x270 sock_close+0x1c/0x30 __fput+0x401/0xb50 task_work_run+0x172/0x280 exit_to_user_mode_loop+0xff/0x4d0 do_syscall_64+0x3c3/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 0 UID: 0 PID: 123522 Comm: syz-executor.4 Not tainted 6.18.0-rc7-next-20251126 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0xca/0x120 check_irq_usage+0x831/0xb40 __lock_acquire+0x13fb/0x2150 lock_acquire+0x15e/0x2d0 _raw_read_lock_irqsave+0x75/0x90 send_sigio+0x31/0x370 kill_fasync+0x218/0x520 sock_wake_async+0xd6/0x160 unix_release_sock+0xb60/0x1320 unix_release+0x91/0xf0 __sock_release+0xb3/0x270 sock_close+0x1c/0x30 __fput+0x401/0xb50 task_work_run+0x172/0x280 exit_to_user_mode_loop+0xff/0x4d0 do_syscall_64+0x3c3/0x420 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f700baeeb19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7009064188 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f700bc01f60 RCX: 00007f700baeeb19 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000004 RBP: 00007f700bb48f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc6596f81f R14: 00007f7009064300 R15: 0000000000022000 netlink: 'syz-executor.2': attribute type 16 has an invalid length. netlink: 'syz-executor.0': attribute type 16 has an invalid length. netlink: 'syz-executor.2': attribute type 16 has an invalid length. netlink: 'syz-executor.0': attribute type 16 has an invalid length. netlink: 'syz-executor.2': attribute type 16 has an invalid length. netlink: 'syz-executor.0': attribute type 16 has an invalid length.