INFO: task syz.5.5652:18308 blocked for more than 122 seconds.
Not tainted 6.12.38-syzkaller-g0d89690c20b1 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.5652 state:D stack:0 pid:18308 tgid:18307 ppid:9399 flags:0x00004002
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:10868
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: 0033:0x7f123478ebe9
RSP: 002b:00007f123568c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: 0000000000018ff8 RBX: 00007f12349b5fa0 RCX: 00007f123478ebe9
RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 0000000000000008
RBP: 00007f1234811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f12349b6038 R14: 00007f12349b5fa0 R15: 00007fff5aa746e8
INFO: task syz.4.5718:18517 blocked for more than 123 seconds.
Not tainted 6.12.38-syzkaller-g0d89690c20b1 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.5718 state:D stack:0 pid:18517 tgid:18517 ppid:18311 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_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
netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10868
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: 0033:0x7f53ebfc14a5
RSP: 002b:00007f53ecde3f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f53ec1b5fa0 RCX: 00007f53ebfc14a5
RDX: 00007f53ecde3fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f53ec011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f53ec1b6038 R14: 00007f53ec1b5fa0 R15: 00007ffdd9a317b8
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.38-syzkaller-g0d89690c20b1 #0 70853a5d0159a4d1ba77fadacda2dadb70163b96
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2452 Comm: kworker/u8:12 Not tainted 6.12.38-syzkaller-g0d89690c20b1 #0 70853a5d0159a4d1ba77fadacda2dadb70163b96
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:skb_flow_limit net/core/dev.c:-1 [inline]
RIP: 0010:enqueue_to_backlog+0x290/0xbf0 net/core/dev.c:4962
Code: 41 d1 ff 44 8b 6d 9c 44 89 ef 44 89 fe e8 58 2c 17 fd 45 39 fd 48 89 5d 80 73 14 e8 8a 2a 17 fd 49 bf 00 00 00 00 00 fc ff df c9 02 00 00 65 48 8b 1d 5b 5d 93 7b e8 de 80 00 fd 4c 8d bb 80
RSP: 0018:ffffc9000022ffa0 EFLAGS: 00000046
RAX: ffffffff846eb436 RBX: ffff8881f6f51044 RCX: ffff888110c31300
RDX: 0000000000000100 RSI: 00000000000001f4 RDI: 0000000000000004
RBP: ffffc90000230050 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000045fe0 R12: 1ffff1102ed8e02a
R13: 0000000000000004 R14: ffff888176c70140 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f578e90b90 CR3: 000000010bbda000 CR4: 00000000003526b0
Call Trace:
netif_rx_internal+0xab/0x340 net/core/dev.c:5281
__netif_rx+0x24/0x230 net/core/dev.c:5301
veth_forward_skb drivers/net/veth.c:322 [inline]
veth_xmit+0x460/0x820 drivers/net/veth.c:375
__netdev_start_xmit include/linux/netdevice.h:4975 [inline]
netdev_start_xmit include/linux/netdevice.h:4984 [inline]
xmit_one net/core/dev.c:3662 [inline]
dev_hard_start_xmit+0x218/0x770 net/core/dev.c:3678
__dev_queue_xmit+0x19cc/0x3790 net/core/dev.c:4514
dev_queue_xmit include/linux/netdevice.h:3141 [inline]
br_dev_queue_push_xmit+0x553/0x6d0 net/bridge/br_forward.c:53
NF_HOOK include/linux/netfilter.h:317 [inline]
br_forward_finish net/bridge/br_forward.c:66 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
__br_forward+0x25c/0x390 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver net/bridge/br_forward.c:190 [inline]
br_flood+0x50e/0x730 net/bridge/br_forward.c:236
br_handle_frame_finish+0x12bb/0x1720 net/bridge/br_input.c:215
nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424
__netif_receive_skb_core+0xf48/0x3940 net/core/dev.c:5651
__netif_receive_skb_one_core net/core/dev.c:5755 [inline]
__netif_receive_skb net/core/dev.c:5870 [inline]
process_backlog+0x3e5/0xae0 net/core/dev.c:6206
__napi_poll+0xd0/0x610 net/core/dev.c:6857
napi_poll net/core/dev.c:6926 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7048
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_write_unlock_bh include/linux/rwlock_api_smp.h:281 [inline]
_raw_write_unlock_bh+0x33/0x70 kernel/locking/spinlock.c:366
___neigh_create+0x1e27/0x2160 net/core/neighbour.c:720
__neigh_create+0x72/0xb0 net/core/neighbour.c:739
ip6_finish_output2+0xafa/0x1990 net/ipv6/ip6_output.c:132
__ip6_finish_output net/ipv6/ip6_output.c:215 [inline]
ip6_finish_output+0x54f/0xb10 net/ipv6/ip6_output.c:226
NF_HOOK_COND include/linux/netfilter.h:306 [inline]
ip6_output+0x1d5/0x3c0 net/ipv6/ip6_output.c:247
dst_output include/net/dst.h:459 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
mld_sendpack+0x780/0xd50 net/ipv6/mcast.c:1825
mld_send_initial_cr+0x1c0/0x320 net/ipv6/mcast.c:2242
ipv6_mc_dad_complete+0x8b/0x460 net/ipv6/mcast.c:2250
addrconf_dad_completed+0x6ae/0xef0 net/ipv6/addrconf.c:4386
addrconf_dad_work+0xc2f/0x14e0 net/ipv6/addrconf.c:-1
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: 89344 callbacks suppressed
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:0e:a3:13:2f:20:dd, 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 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 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:0e:a3:13:2f:20:dd, vlan:0)