INFO: task syz.0.17:6497 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:27560 pid:6497 tgid:6495 ppid:6403 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5263 [inline]
__schedule+0x1836/0x4ed0 kernel/sched/core.c:6871
__schedule_loop kernel/sched/core.c:6953 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6968
request_wait_answer fs/fuse/dev.c:585 [inline]
__fuse_request_send fs/fuse/dev.c:599 [inline]
__fuse_simple_request+0x11d2/0x1bb0 fs/fuse/dev.c:693
fuse_simple_request fs/fuse/fuse_i.h:1251 [inline]
fuse_do_setattr+0xfac/0x1a30 fs/fuse/dir.c:2230
fuse_setattr+0x546/0xae0 fs/fuse/dir.c:2351
notify_change+0xc1a/0xf40 fs/attr.c:546
chmod_common+0x248/0x400 fs/open.c:647
do_fchmodat+0x12d/0x200 fs/open.c:694
__do_sys_chmod fs/open.c:718 [inline]
__se_sys_chmod fs/open.c:716 [inline]
__x64_sys_chmod+0x62/0x70 fs/open.c:716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1594d8eec9
RSP: 002b:00007f15943d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000005a
RAX: ffffffffffffffda RBX: 00007f1594fe6090 RCX: 00007f1594d8eec9
RDX: 0000000000000000 RSI: 00000000000003ca RDI: 0000200000000100
RBP: 00007f1594e11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1594fe6128 R14: 00007f1594fe6090 R15: 00007ffc7ca0ee18
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e33d9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e33d9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e33d9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:6/144:
#0: ffff8880b863a718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
#2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085
#3: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
2 locks held by getty/5588:
#0: ffff888034a5d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.0.17/6497:
#0: ffff88802f698420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff888074b60148 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff888074b60148 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.1.18/6521:
#0: ffff88806d5ae420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff88805d718148 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff88805d718148 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.2.19/6545:
#0: ffff888079c2e420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff88805d718848 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff88805d718848 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.3.20/6575:
#0: ffff888077c6e420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff88805d718f48 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff88805d718f48 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.4.21/6604:
#0: ffff88814b226420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff888074b60848 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff888074b60848 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.5.22/6633:
#0: ffff88805b3ca420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff88805d719648 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff88805d719648 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.6.23/6664:
#0: ffff888058cb6420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff88805d719d48 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff88805d719d48 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.7.24/6703:
#0: ffff888059d04420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff888074b60f48 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff888074b60f48 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
2 locks held by syz.8.25/6737:
#0: ffff888059920420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509
#1: ffff888074b61648 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1032 [inline]
#1: ffff888074b61648 (&type->i_mutex_dir_key#8){+.+.}-{4:4}, at: chmod_common+0x161/0x400 fs/open.c:639
3 locks held by kworker/0:7/6740:
#0: ffff88813fe55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x841/0x15e0 kernel/workqueue.c:3236
#1: ffffc9000498fb80 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15e0 kernel/workqueue.c:3237
#2: ffff888079880240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1f7/0x3b0 drivers/net/netdevsim/fib.c:1490
3 locks held by syz-executor/6742:
#0: ffffffff8f6f4f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f6f4f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f6f4f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
#1: ffff888031d75528 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50
#2: ffffffff8e343478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e343478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfb5/0x1000 kernel/hung_task.c:515
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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3436 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work
RIP: 0010:kasan_check_range+0x5/0x2c0 mm/kasan/generic.c:199
Code: 48 c7 c6 53 a3 c7 8d e8 d9 6b ff fe 90 0f 0b cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 55 <41> 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d
RSP: 0018:ffffc90000a08998 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81c9d828
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fbf8b70
RBP: ffffc90000a08b40 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014115c R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffc90000a08ac0 R15: 0000000000000200
FS: 0000000000000000(0000) GS:ffff888125b6f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd61a2d2e9c CR3: 000000002f706000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
cpumask_test_cpu include/linux/cpumask.h:646 [inline]
cpu_online include/linux/cpumask.h:1205 [inline]
trace_irq_disable+0x28/0x110 include/trace/events/preemptirq.h:36
get_random_u32+0xfc/0x940 drivers/char/random.c:554
__get_random_u32_below+0x14/0x90 drivers/char/random.c:568
get_random_u32_below include/linux/random.h:63 [inline]
mrp_join_timer_arm net/802/mrp.c:596 [inline]
mrp_join_timer+0x10c/0x170 net/802/mrp.c:612
call_timer_fn+0x16e/0x600 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x27d/0x880 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727
irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
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
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2037 [inline]
RIP: 0010:vprintk_emit+0x4ab/0x5d0 kernel/printk/printk.c:2425
Code: 0f 84 34 ff ff ff e8 f4 67 20 00 fb eb 44 e8 ec 67 20 00 e8 97 49 c3 09 4d 85 f6 74 94 e8 dd 67 20 00 fb 48 c7 c7 60 1a 33 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 bd 27
RSP: 0018:ffffc9000be47340 EFLAGS: 00000293
RAX: ffffffff81a197c3 RBX: ffffffff81a1961c RCX: ffff8880309a8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e331a60
RBP: ffffc9000be47450 R08: ffffffff8fbf8b77 R09: 1ffffffff1f7f16e
R10: dffffc0000000000 R11: fffffbfff1f7f16f R12: 0000000000000000
R13: 0000000000000049 R14: 0000000000000200 R15: 1ffff920017c8e6c
dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4970
dev_printk_emit+0xe0/0x130 drivers/base/core.c:4981
__netdev_printk+0x3d7/0x4d0 net/core/dev.c:12912
netdev_info+0x10a/0x160 net/core/dev.c:12967
nsim_udp_tunnel_set_port+0x26e/0x3e0 drivers/net/netdevsim/udp_tunnels.c:31
udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline]
udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline]
__udp_tunnel_nic_device_sync+0xb0f/0x14d0 net/ipv4/udp_tunnel_nic.c:292
udp_tunnel_nic_device_sync_work+0x97/0xa50 net/ipv4/udp_tunnel_nic.c:740
process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261
process_scheduled_works kernel/workqueue.c:3344 [inline]
worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425
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