[v6.6] possible deadlock in evdev_pass_values
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syzbot
Jul 29, 2025, 7:28:31 PM7/29/25
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: dbcb8d8e4163 Linux 6.6.100
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15a25782580000
kernel config: https://syzkaller.appspot.com/x/.config?x=293251cfa8d8100
dashboard link: https://syzkaller.appspot.com/bug?extid=f1cb8bac1f12be8a38f7
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d0b56817a2c3/disk-dbcb8d8e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0d646b2f7fa/vmlinux-dbcb8d8e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e0b752a5011/bzImage-dbcb8d8e.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f1cb8b...@syzkaller.appspotmail.com
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
6.6.100-syzkaller #0 Not tainted
-----------------------------------------------------
syz.8.917/8659 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffffffff8ca0a058 (tasklist_lock){.+.+}-{2:2}, at: send_sigurg+0xf0/0x3c0 fs/fcntl.c:827
and this task is already holding:
ffff88807af4dc98 (&f->f_owner.lock){...-}-{2:2}, at: send_sigurg+0x29/0x3c0 fs/fcntl.c:811
which would create a new lock dependency:
(&f->f_owner.lock){...-}-{2:2} -> (tasklist_lock){.+.+}-{2:2}
but this new dependency connects a SOFTIRQ-irq-safe lock:
(&client->buffer_lock){..-.}-{2:2}
... which became SOFTIRQ-irq-safe at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__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+0xcb/0xab0 drivers/input/evdev.c:261
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x3e8/0x6c0 drivers/input/input.c:389
input_event+0x8c/0xc0 drivers/input/input.c:435
hidinput_hid_event+0x1325/0x1c80 drivers/hid/hid-input.c:1716
hid_process_event+0x4b7/0x620 drivers/hid/hid-core.c:1542
hid_process_report drivers/hid/hid-core.c:1690 [inline]
hid_report_raw_event+0xf46/0x1760 drivers/hid/hid-core.c:2026
hid_input_report+0x434/0x520 drivers/hid/hid-core.c:2100
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8a3/0x31b0 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1755 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
to a SOFTIRQ-irq-unsafe lock:
(tasklist_lock){.+.+}-{2:2}
... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
other info that might help us debug this:
Chain exists of:
&client->buffer_lock --> &f->f_owner.lock --> tasklist_lock
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(tasklist_lock);
local_irq_disable();
lock(&client->buffer_lock);
lock(&f->f_owner.lock);
<Interrupt>
lock(&client->buffer_lock);
*** DEADLOCK ***
2 locks held by syz.8.917/8659:
#0: ffff88807e6e8e78 (&u->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#0: ffff88807e6e8e78 (&u->lock){+.+.}-{2:2}, at: queue_oob+0x1cb/0x4e0 net/unix/af_unix.c:2190
#1: ffff88807af4dc98 (&f->f_owner.lock){...-}-{2:2}, at: send_sigurg+0x29/0x3c0 fs/fcntl.c:811
the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&client->buffer_lock){..-.}-{2:2} {
IN-SOFTIRQ-W at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__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+0xcb/0xab0 drivers/input/evdev.c:261
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x3e8/0x6c0 drivers/input/input.c:389
input_event+0x8c/0xc0 drivers/input/input.c:435
hidinput_hid_event+0x1325/0x1c80 drivers/hid/hid-input.c:1716
hid_process_event+0x4b7/0x620 drivers/hid/hid-core.c:1542
hid_process_report drivers/hid/hid-core.c:1690 [inline]
hid_report_raw_event+0xf46/0x1760 drivers/hid/hid-core.c:2026
hid_input_report+0x434/0x520 drivers/hid/hid-core.c:2100
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8a3/0x31b0 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1755 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__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+0xcb/0xab0 drivers/input/evdev.c:261
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x3e8/0x6c0 drivers/input/input.c:389
input_event+0x8c/0xc0 drivers/input/input.c:435
hidinput_hid_event+0x1325/0x1c80 drivers/hid/hid-input.c:1716
hid_process_event+0x4b7/0x620 drivers/hid/hid-core.c:1542
hid_process_report drivers/hid/hid-core.c:1690 [inline]
hid_report_raw_event+0xf46/0x1760 drivers/hid/hid-core.c:2026
hid_input_report+0x434/0x520 drivers/hid/hid-core.c:2100
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8a3/0x31b0 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1755 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
}
... key at: [<ffffffff9720e8a0>] evdev_open.__key.28+0x0/0x20
-> (&new->fa_lock){....}-{2:2} {
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
_raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
fasync_insert_entry+0xc8/0x270 fs/fcntl.c:914
lease_setup+0x86/0x110 fs/locks.c:537
generic_add_lease fs/locks.c:1815 [inline]
generic_setlease+0xe32/0x1270 fs/locks.c:1895
vfs_setlease fs/locks.c:1960 [inline]
do_fcntl_add_lease fs/locks.c:1981 [inline]
fcntl_setlease+0x268/0x340 fs/locks.c:2003
do_fcntl+0x1cb/0x1380 fs/fcntl.c:397
__do_sys_fcntl fs/fcntl.c:448 [inline]
__se_sys_fcntl+0xc9/0x1a0 fs/fcntl.c:433
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
INITIAL READ USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:990 [inline]
kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
lease_break_callback+0x26/0x30 fs/locks.c:522
__break_lease+0x4a7/0x12c0 fs/locks.c:1537
break_lease include/linux/filelock.h:360 [inline]
do_dentry_open+0x823/0x1500 fs/open.c:920
do_open fs/namei.c:3632 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
}
... key at: [<ffffffff96f15ac0>] fasync_insert_entry.__key+0x0/0x20
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:990 [inline]
kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
__pass_event drivers/input/evdev.c:240 [inline]
evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
input_inject_event+0x1f9/0x320 drivers/input/input.c:465
evdev_write+0x32a/0x470 drivers/input/evdev.c:530
vfs_write+0x288/0x940 fs/read_write.c:582
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> (&f->f_owner.lock){...-}-{2:2} {
IN-SOFTIRQ-R at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
send_sigurg+0x29/0x3c0 fs/fcntl.c:811
sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3387
tcp_check_urg+0x200/0x750 net/ipv4/tcp_input.c:5770
tcp_urg+0x161/0x3f0 net/ipv4/tcp_input.c:5811
tcp_rcv_established+0xa2e/0x1cf0 net/ipv4/tcp_input.c:6166
tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734
tcp_v4_rcv+0x2334/0x2a50 net/ipv4/tcp_ipv4.c:2166
ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233
NF_HOOK+0x303/0x390 include/linux/netfilter.h:304
NF_HOOK+0x303/0x390 include/linux/netfilter.h:304
__netif_receive_skb_one_core net/core/dev.c:5596 [inline]
__netif_receive_skb+0xcc/0x290 net/core/dev.c:5710
process_backlog+0x380/0x6e0 net/core/dev.c:6038
__napi_poll+0xc0/0x460 net/core/dev.c:6600
napi_poll net/core/dev.c:6667 [inline]
net_rx_action+0x5ea/0xbf0 net/core/dev.c:6803
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:147
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1eb/0x510 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
secondary_startup_64_no_verify+0x179/0x17b
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
_raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
__f_setown+0x3b/0x330 fs/fcntl.c:92
generic_add_lease fs/locks.c:1815 [inline]
generic_setlease+0xe32/0x1270 fs/locks.c:1895
vfs_setlease fs/locks.c:1960 [inline]
do_fcntl_add_lease fs/locks.c:1981 [inline]
fcntl_setlease+0x268/0x340 fs/locks.c:2003
do_fcntl+0x1cb/0x1380 fs/fcntl.c:397
__do_sys_fcntl fs/fcntl.c:448 [inline]
__se_sys_fcntl+0xc9/0x1a0 fs/fcntl.c:433
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
INITIAL READ USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
send_sigio+0x33/0x360 fs/fcntl.c:772
kill_fasync_rcu fs/fcntl.c:997 [inline]
kill_fasync+0x228/0x4b0 fs/fcntl.c:1011
lease_break_callback+0x26/0x30 fs/locks.c:522
__break_lease+0x4a7/0x12c0 fs/locks.c:1537
break_lease include/linux/filelock.h:360 [inline]
do_dentry_open+0x823/0x1500 fs/open.c:920
do_open fs/namei.c:3632 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
}
... key at: [<ffffffff96f14e40>] init_file.__key+0x0/0x20
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
send_sigio+0x33/0x360 fs/fcntl.c:772
kill_fasync_rcu fs/fcntl.c:997 [inline]
kill_fasync+0x228/0x4b0 fs/fcntl.c:1011
lease_break_callback+0x26/0x30 fs/locks.c:522
__break_lease+0x4a7/0x12c0 fs/locks.c:1537
break_lease include/linux/filelock.h:360 [inline]
do_dentry_open+0x823/0x1500 fs/open.c:920
do_open fs/namei.c:3632 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
the dependencies between the lock to be acquired
and SOFTIRQ-irq-unsafe lock:
-> (tasklist_lock){.+.+}-{2:2} {
HARDIRQ-ON-R at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
SOFTIRQ-ON-R at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
_raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
copy_process+0x225d/0x3d70 kernel/fork.c:2631
kernel_clone+0x21b/0x840 kernel/fork.c:2914
user_mode_thread+0xde/0x130 kernel/fork.c:2992
rest_init+0x27/0x300 init/main.c:697
arch_call_rest_init+0xe/0x10 init/main.c:829
start_kernel+0x459/0x4e0 init/main.c:1074
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
copy_bootdata+0x0/0xe0 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x179/0x17b
INITIAL READ USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
}
... key at: [<ffffffff8ca0a058>] 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+0xf0/0x3c0 fs/fcntl.c:827
sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3387
queue_oob+0x3d7/0x4e0 net/unix/af_unix.c:2207
unix_stream_sendmsg+0xaa2/0xba0 net/unix/af_unix.c:2326
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
___sys_sendmsg+0x220/0x290 net/socket.c:2649
__sys_sendmmsg+0x275/0x4a0 net/socket.c:2735
__do_sys_sendmmsg net/socket.c:2764 [inline]
__se_sys_sendmmsg net/socket.c:2761 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
stack backtrace:
CPU: 0 PID: 8659 Comm: syz.8.917 Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline]
check_irq_usage kernel/locking/lockdep.c:2865 [inline]
check_prev_add kernel/locking/lockdep.c:3138 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x678f/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
send_sigurg+0xf0/0x3c0 fs/fcntl.c:827
sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3387
queue_oob+0x3d7/0x4e0 net/unix/af_unix.c:2207
unix_stream_sendmsg+0xaa2/0xba0 net/unix/af_unix.c:2326
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
___sys_sendmsg+0x220/0x290 net/socket.c:2649
__sys_sendmmsg+0x275/0x4a0 net/socket.c:2735
__do_sys_sendmmsg net/socket.c:2764 [inline]
__se_sys_sendmmsg net/socket.c:2761 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7292f8e9a9
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:00007f7292dff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f72931b5fa0 RCX: 00007f7292f8e9a9
RDX: 0000000000000001 RSI: 0000200000006c40 RDI: 0000000000000003
RBP: 00007f7293010d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000040015 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f72931b5fa0 R15: 00007ffdd56c5088
</TASK>
---
This report is generated by a bot. It may contain errors.
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#syz undup
syzbot found the following issue on:
HEAD commit: dbcb8d8e4163 Linux 6.6.100
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15a25782580000
kernel config: https://syzkaller.appspot.com/x/.config?x=293251cfa8d8100
dashboard link: https://syzkaller.appspot.com/bug?extid=f1cb8bac1f12be8a38f7
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d0b56817a2c3/disk-dbcb8d8e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0d646b2f7fa/vmlinux-dbcb8d8e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e0b752a5011/bzImage-dbcb8d8e.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f1cb8b...@syzkaller.appspotmail.com
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
6.6.100-syzkaller #0 Not tainted
-----------------------------------------------------
syz.8.917/8659 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffffffff8ca0a058 (tasklist_lock){.+.+}-{2:2}, at: send_sigurg+0xf0/0x3c0 fs/fcntl.c:827
and this task is already holding:
ffff88807af4dc98 (&f->f_owner.lock){...-}-{2:2}, at: send_sigurg+0x29/0x3c0 fs/fcntl.c:811
which would create a new lock dependency:
(&f->f_owner.lock){...-}-{2:2} -> (tasklist_lock){.+.+}-{2:2}
but this new dependency connects a SOFTIRQ-irq-safe lock:
(&client->buffer_lock){..-.}-{2:2}
... which became SOFTIRQ-irq-safe at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__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+0xcb/0xab0 drivers/input/evdev.c:261
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x3e8/0x6c0 drivers/input/input.c:389
input_event+0x8c/0xc0 drivers/input/input.c:435
hidinput_hid_event+0x1325/0x1c80 drivers/hid/hid-input.c:1716
hid_process_event+0x4b7/0x620 drivers/hid/hid-core.c:1542
hid_process_report drivers/hid/hid-core.c:1690 [inline]
hid_report_raw_event+0xf46/0x1760 drivers/hid/hid-core.c:2026
hid_input_report+0x434/0x520 drivers/hid/hid-core.c:2100
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8a3/0x31b0 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1755 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
to a SOFTIRQ-irq-unsafe lock:
(tasklist_lock){.+.+}-{2:2}
... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
other info that might help us debug this:
Chain exists of:
&client->buffer_lock --> &f->f_owner.lock --> tasklist_lock
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(tasklist_lock);
local_irq_disable();
lock(&client->buffer_lock);
lock(&f->f_owner.lock);
<Interrupt>
lock(&client->buffer_lock);
*** DEADLOCK ***
2 locks held by syz.8.917/8659:
#0: ffff88807e6e8e78 (&u->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#0: ffff88807e6e8e78 (&u->lock){+.+.}-{2:2}, at: queue_oob+0x1cb/0x4e0 net/unix/af_unix.c:2190
#1: ffff88807af4dc98 (&f->f_owner.lock){...-}-{2:2}, at: send_sigurg+0x29/0x3c0 fs/fcntl.c:811
the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&client->buffer_lock){..-.}-{2:2} {
IN-SOFTIRQ-W at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__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+0xcb/0xab0 drivers/input/evdev.c:261
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x3e8/0x6c0 drivers/input/input.c:389
input_event+0x8c/0xc0 drivers/input/input.c:435
hidinput_hid_event+0x1325/0x1c80 drivers/hid/hid-input.c:1716
hid_process_event+0x4b7/0x620 drivers/hid/hid-core.c:1542
hid_process_report drivers/hid/hid-core.c:1690 [inline]
hid_report_raw_event+0xf46/0x1760 drivers/hid/hid-core.c:2026
hid_input_report+0x434/0x520 drivers/hid/hid-core.c:2100
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8a3/0x31b0 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1755 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__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+0xcb/0xab0 drivers/input/evdev.c:261
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x3e8/0x6c0 drivers/input/input.c:389
input_event+0x8c/0xc0 drivers/input/input.c:435
hidinput_hid_event+0x1325/0x1c80 drivers/hid/hid-input.c:1716
hid_process_event+0x4b7/0x620 drivers/hid/hid-core.c:1542
hid_process_report drivers/hid/hid-core.c:1690 [inline]
hid_report_raw_event+0xf46/0x1760 drivers/hid/hid-core.c:2026
hid_input_report+0x434/0x520 drivers/hid/hid-core.c:2100
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8a3/0x31b0 drivers/usb/gadget/udc/dummy_hcd.c:1993
__run_hrtimer kernel/time/hrtimer.c:1755 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
}
... key at: [<ffffffff9720e8a0>] evdev_open.__key.28+0x0/0x20
-> (&new->fa_lock){....}-{2:2} {
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
_raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
fasync_insert_entry+0xc8/0x270 fs/fcntl.c:914
lease_setup+0x86/0x110 fs/locks.c:537
generic_add_lease fs/locks.c:1815 [inline]
generic_setlease+0xe32/0x1270 fs/locks.c:1895
vfs_setlease fs/locks.c:1960 [inline]
do_fcntl_add_lease fs/locks.c:1981 [inline]
fcntl_setlease+0x268/0x340 fs/locks.c:2003
do_fcntl+0x1cb/0x1380 fs/fcntl.c:397
__do_sys_fcntl fs/fcntl.c:448 [inline]
__se_sys_fcntl+0xc9/0x1a0 fs/fcntl.c:433
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
INITIAL READ USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:990 [inline]
kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
lease_break_callback+0x26/0x30 fs/locks.c:522
__break_lease+0x4a7/0x12c0 fs/locks.c:1537
break_lease include/linux/filelock.h:360 [inline]
do_dentry_open+0x823/0x1500 fs/open.c:920
do_open fs/namei.c:3632 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
}
... key at: [<ffffffff96f15ac0>] fasync_insert_entry.__key+0x0/0x20
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:990 [inline]
kill_fasync+0x192/0x4b0 fs/fcntl.c:1011
__pass_event drivers/input/evdev.c:240 [inline]
evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278
evdev_events+0x1d8/0x330 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x907/0x1300 drivers/input/input.c:161
input_event_dispose+0x346/0x6c0 drivers/input/input.c:378
input_inject_event+0x1f9/0x320 drivers/input/input.c:465
evdev_write+0x32a/0x470 drivers/input/evdev.c:530
vfs_write+0x288/0x940 fs/read_write.c:582
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> (&f->f_owner.lock){...-}-{2:2} {
IN-SOFTIRQ-R at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
send_sigurg+0x29/0x3c0 fs/fcntl.c:811
sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3387
tcp_check_urg+0x200/0x750 net/ipv4/tcp_input.c:5770
tcp_urg+0x161/0x3f0 net/ipv4/tcp_input.c:5811
tcp_rcv_established+0xa2e/0x1cf0 net/ipv4/tcp_input.c:6166
tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734
tcp_v4_rcv+0x2334/0x2a50 net/ipv4/tcp_ipv4.c:2166
ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233
NF_HOOK+0x303/0x390 include/linux/netfilter.h:304
NF_HOOK+0x303/0x390 include/linux/netfilter.h:304
__netif_receive_skb_one_core net/core/dev.c:5596 [inline]
__netif_receive_skb+0xcc/0x290 net/core/dev.c:5710
process_backlog+0x380/0x6e0 net/core/dev.c:6038
__napi_poll+0xc0/0x460 net/core/dev.c:6600
napi_poll net/core/dev.c:6667 [inline]
net_rx_action+0x5ea/0xbf0 net/core/dev.c:6803
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:147
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1eb/0x510 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
secondary_startup_64_no_verify+0x179/0x17b
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
_raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
__f_setown+0x3b/0x330 fs/fcntl.c:92
generic_add_lease fs/locks.c:1815 [inline]
generic_setlease+0xe32/0x1270 fs/locks.c:1895
vfs_setlease fs/locks.c:1960 [inline]
do_fcntl_add_lease fs/locks.c:1981 [inline]
fcntl_setlease+0x268/0x340 fs/locks.c:2003
do_fcntl+0x1cb/0x1380 fs/fcntl.c:397
__do_sys_fcntl fs/fcntl.c:448 [inline]
__se_sys_fcntl+0xc9/0x1a0 fs/fcntl.c:433
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
INITIAL READ USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
send_sigio+0x33/0x360 fs/fcntl.c:772
kill_fasync_rcu fs/fcntl.c:997 [inline]
kill_fasync+0x228/0x4b0 fs/fcntl.c:1011
lease_break_callback+0x26/0x30 fs/locks.c:522
__break_lease+0x4a7/0x12c0 fs/locks.c:1537
break_lease include/linux/filelock.h:360 [inline]
do_dentry_open+0x823/0x1500 fs/open.c:920
do_open fs/namei.c:3632 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
}
... key at: [<ffffffff96f14e40>] init_file.__key+0x0/0x20
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:236
send_sigio+0x33/0x360 fs/fcntl.c:772
kill_fasync_rcu fs/fcntl.c:997 [inline]
kill_fasync+0x228/0x4b0 fs/fcntl.c:1011
lease_break_callback+0x26/0x30 fs/locks.c:522
__break_lease+0x4a7/0x12c0 fs/locks.c:1537
break_lease include/linux/filelock.h:360 [inline]
do_dentry_open+0x823/0x1500 fs/open.c:920
do_open fs/namei.c:3632 [inline]
path_openat+0x274b/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
the dependencies between the lock to be acquired
and SOFTIRQ-irq-unsafe lock:
-> (tasklist_lock){.+.+}-{2:2} {
HARDIRQ-ON-R at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
SOFTIRQ-ON-R at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
INITIAL USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline]
_raw_write_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:326
copy_process+0x225d/0x3d70 kernel/fork.c:2631
kernel_clone+0x21b/0x840 kernel/fork.c:2914
user_mode_thread+0xde/0x130 kernel/fork.c:2992
rest_init+0x27/0x300 init/main.c:697
arch_call_rest_init+0xe/0x10 init/main.c:829
start_kernel+0x459/0x4e0 init/main.c:1074
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
copy_bootdata+0x0/0xe0 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x179/0x17b
INITIAL READ USE at:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
do_wait+0x294/0xaf0 kernel/exit.c:1607
kernel_wait+0xac/0x170 kernel/exit.c:1797
call_usermodehelper_exec_sync kernel/umh.c:137 [inline]
call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
}
... key at: [<ffffffff8ca0a058>] 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+0xf0/0x3c0 fs/fcntl.c:827
sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3387
queue_oob+0x3d7/0x4e0 net/unix/af_unix.c:2207
unix_stream_sendmsg+0xaa2/0xba0 net/unix/af_unix.c:2326
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
___sys_sendmsg+0x220/0x290 net/socket.c:2649
__sys_sendmmsg+0x275/0x4a0 net/socket.c:2735
__do_sys_sendmmsg net/socket.c:2764 [inline]
__se_sys_sendmmsg net/socket.c:2761 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
stack backtrace:
CPU: 0 PID: 8659 Comm: syz.8.917 Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline]
check_irq_usage kernel/locking/lockdep.c:2865 [inline]
check_prev_add kernel/locking/lockdep.c:3138 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x678f/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
send_sigurg+0xf0/0x3c0 fs/fcntl.c:827
sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3387
queue_oob+0x3d7/0x4e0 net/unix/af_unix.c:2207
unix_stream_sendmsg+0xaa2/0xba0 net/unix/af_unix.c:2326
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x5bf/0x950 net/socket.c:2595
___sys_sendmsg+0x220/0x290 net/socket.c:2649
__sys_sendmmsg+0x275/0x4a0 net/socket.c:2735
__do_sys_sendmmsg net/socket.c:2764 [inline]
__se_sys_sendmmsg net/socket.c:2761 [inline]
__x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7292f8e9a9
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:00007f7292dff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f72931b5fa0 RCX: 00007f7292f8e9a9
RDX: 0000000000000001 RSI: 0000200000006c40 RDI: 0000000000000003
RBP: 00007f7293010d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000040015 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f72931b5fa0 R15: 00007ffdd56c5088
</TASK>
---
This report is generated by a bot. It may contain errors.
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syzbot
Nov 15, 2025, 8:39:11 AM11/15/25
to syzkaller...@googlegroups.com
Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.
Crashes did not happen for a while, no reproducer and no activity.
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