INFO: task kworker/1:4:439 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:4 state:D stack:0 pid:439 tgid:439 ppid:2 flags:0x00004000
Workqueue: events fqdir_free_fn
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589
fqdir_free_fn+0x36/0x150 net/ipv4/inet_fragment.c:167
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
INFO: task syz.2.834:2776 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.834 state:D stack:0 pid:2776 tgid:2776 ppid:296 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4657
netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10880
rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
tun_detach drivers/net/tun.c:704 [inline]
tun_chr_close+0xc5/0x150 drivers/net/tun.c:3517
__fput+0x1fb/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e0/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
get_signal+0x139d/0x14f0 kernel/signal.c:2933
arch_do_signal_or_restart+0x96/0x720 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+0x58/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f97ce1c1885
RSP: 002b:00007f97cf02af80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f97ce3e5fa0 RCX: 00007f97ce1c1885
RDX: 00007f97cf02afc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f97ce211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f97ce3e6038 R14: 00007f97ce3e5fa0 R15: 00007ffeb6021c48
INFO: task syz.1.882:2913 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.882 state:D stack:0 pid:2913 tgid:2912 ppid:289 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589
setup_net+0x8cf/0x990 net/core/net_namespace.c:394
copy_net_ns+0x513/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
copy_namespaces+0x25d/0x2b0 kernel/nsproxy.c:179
copy_process+0x126d/0x3220 kernel/fork.c:2409
kernel_clone+0x23f/0x830 kernel/fork.c:2819
__do_sys_clone kernel/fork.c:2964 [inline]
__se_sys_clone kernel/fork.c:2948 [inline]
__x64_sys_clone+0x18c/0x1f0 kernel/fork.c:2948
x64_sys_call+0x2b3c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:57
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f3c2998efc9
RSP: 002b:00007f3c2a8d6fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f3c29be5fa0 RCX: 00007f3c2998efc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040800000
RBP: 00007f3c29a11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f3c29be6038 R14: 00007f3c29be5fa0 R15: 00007fff3ae5dfc8
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xd8f/0xed0 kernel/hung_task.c:423
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: netns cleanup_net
RIP: 0010:ipv6_masked_addr_cmp include/net/ipv6.h:590 [inline]
RIP: 0010:ip6_packet_match net/ipv6/netfilter/ip6_tables.c:57 [inline]
RIP: 0010:ip6t_do_table+0x415/0x14d0 net/ipv6/netfilter/ip6_tables.c:306
Code: fc 4c 8b 23 48 8b 84 24 10 01 00 00 42 0f b6 04 28 84 c0 0f 85 64 0c 00 00 48 8b 84 24 88 00 00 00 44 0f b7 38 4b 8d 5c 3c 08 <48> 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 25 b0 e6 fc
RSP: 0018:ffffc90000007780 EFLAGS: 00000246
RAX: ffff88815b4ad5b8 RBX: ffff888161e36a18 RCX: ffff888103652600
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff888114f6300c
RBP: ffffc90000007970 R08: ffff888114f63000 R09: 0000000000000000
R10: ffffc900000078d0 R11: fffff52000000f1e R12: ffff888161e36a00
R13: dffffc0000000000 R14: ffff888114f63040 R15: 0000000000000010
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b927f84c0 CR3: 0000000109fe6000 CR4: 00000000003526b0
Call Trace:
ip6table_mangle_hook+0x29a/0x6b0 net/ipv6/netfilter/ip6table_mangle.c:73
nf_hook_entry_hookfn include/linux/netfilter.h:155 [inline]
nf_hook_slow+0xd2/0x240 net/netfilter/core.c:626
nf_hook include/linux/netfilter.h:272 [inline]
NF_HOOK include/linux/netfilter.h:315 [inline]
ipv6_rcv+0x1c7/0x220 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5769 [inline]
__netif_receive_skb net/core/dev.c:5882 [inline]
process_backlog+0x44b/0xae0 net/core/dev.c:6218
__napi_poll+0xd3/0x610 net/core/dev.c:6869
napi_poll net/core/dev.c:6938 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7060
handle_softirqs+0x1ab/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xa6/0x100 kernel/softirq.c:503
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
addrconf_ifdown+0x608/0x1940 net/ipv6/addrconf.c:3950
addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1
notifier_call_chain+0x10b/0x2c0 kernel/notifier.c:93
raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:2067 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2105 [inline]
call_netdevice_notifiers net/core/dev.c:2119 [inline]
unregister_netdevice_many_notify+0xe32/0x1bd0 net/core/dev.c:11501
unregister_netdevice_many+0x1d/0x30 net/core/dev.c:11563
cleanup_net+0x62d/0xc70 net/core/net_namespace.c:637
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
net_ratelimit: 128212 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:a6:2a:81:92:6d:91, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:a6:2a:81:92:6d:91, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)