INFO: task syz.0.321:1290 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.321 state:D stack:0 pid:1290 tgid:1290 ppid:289 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
__schedule_loop kernel/sched/core.c:7924 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7939
schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x369/0x650 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
rcu_barrier+0x415/0x540 kernel/rcu/tree.c:4657
netdev_run_todo+0x118/0xce0 net/core/dev.c:10874
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:3520
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e5/0x260 kernel/task_work.c:246
resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x63/0xb0 kernel/entry/common.c:218
do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f71f499aeb9
RSP: 002b:00007ffc103607f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f71f4c17da0 RCX: 00007f71f499aeb9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f71f4c17da0 R08: 00007f71f4c16038 R09: 0000000000000000
R10: 0000000000de22f8 R11: 0000000000000246 R12: 0000000000012554
R13: 00007f71f4c15fac R14: 0000000000012485 R15: 00007ffc10360900
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0044b833cf02edb59ee897eae4c42c13324c9de7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2ba/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+0xdad/0xf00 kernel/hung_task.c:423
kthread+0x2c9/0x370 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: 1351 Comm: syz-executor Not tainted syzkaller #0 0044b833cf02edb59ee897eae4c42c13324c9de7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__in6_dev_get include/net/addrconf.h:342 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:433 [inline]
RIP: 0010:find_match+0xbb/0x10e0 net/ipv6/route.c:781
Code: 74 08 48 89 df e8 45 86 e8 fc 48 89 d8 bb c0 00 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 48 89 df e8 1b 86 e8 fc 48 8b 1b 48 85 db 0f 84 e5 0b 00 00
RSP: 0018:ffffc9000022fc38 EFLAGS: 00000246
RAX: 1ffff110211fa418 RBX: ffff888108fd20c0 RCX: dffffc0000000000
RDX: ffff888131b81300 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000022fcf0 R08: ffffc9000022ff80 R09: ffffc9000022ff90
R10: ffffc900002300f0 R11: fffff52000046022 R12: 0000000000000001
R13: 1ffff110217fda18 R14: 0000000000000003 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd568747e20 CR3: 00000000074a8000 CR4: 00000000003526b0
Call Trace:
__find_rr_leaf+0x24e/0x840 net/ipv6/route.c:869
find_rr_leaf net/ipv6/route.c:890 [inline]
rt6_select net/ipv6/route.c:934 [inline]
fib6_table_lookup+0x2ee/0x9e0 net/ipv6/route.c:2241
ip6_pol_route+0x17a/0x1360 net/ipv6/route.c:2277
ip6_pol_route_input+0x5a/0x80 net/ipv6/route.c:2334
pol_lookup_func include/net/ip6_fib.h:626 [inline]
fib6_rule_lookup+0x4ee/0x6d0 net/ipv6/fib6_rules.c:117
ip6_route_input_lookup net/ipv6/route.c:2346 [inline]
ip6_route_input+0x62e/0x8f0 net/ipv6/route.c:2642
ip6_rcv_finish_core net/ipv6/ip6_input.c:66 [inline]
ip6_rcv_finish+0x15a/0x3e0 net/ipv6/ip6_input.c:77
NF_HOOK include/linux/netfilter.h:317 [inline]
ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5763 [inline]
__netif_receive_skb net/core/dev.c:5876 [inline]
netif_receive_skb_internal net/core/dev.c:5962 [inline]
netif_receive_skb+0x147/0x7b0 net/core/dev.c:6021
br_netif_receive_skb net/bridge/br_input.c:30 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
br_pass_frame_up+0x126/0x1b0 net/bridge/br_input.c:70
br_handle_frame_finish+0x1317/0x1760 net/bridge/br_input.c:221
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+0xfae/0x3ab0 net/core/dev.c:5657
__netif_receive_skb_one_core net/core/dev.c:5761 [inline]
__netif_receive_skb net/core/dev.c:5876 [inline]
process_backlog+0x3e5/0xad0 net/core/dev.c:6212
__napi_poll+0xd3/0x610 net/core/dev.c:6863
napi_poll net/core/dev.c:6932 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7054
handle_softirqs+0x1aa/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xb8/0x110 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+0x614/0x1980 net/ipv6/addrconf.c:3950
addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1
notifier_call_chain+0x10e/0x2b0 kernel/notifier.c:93
raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:2061 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2099 [inline]
call_netdevice_notifiers net/core/dev.c:2113 [inline]
dev_close_many+0x33b/0x4f0 net/core/dev.c:1654
unregister_netdevice_many_notify+0x4bb/0x1c30 net/core/dev.c:11469
unregister_netdevice_many net/core/dev.c:11557 [inline]
unregister_netdevice_queue+0x341/0x390 net/core/dev.c:11431
unregister_netdevice include/linux/netdevice.h:3165 [inline]
__tun_detach+0xca1/0x1460 drivers/net/tun.c:685
tun_detach drivers/net/tun.c:701 [inline]
tun_chr_close+0x93/0x150 drivers/net/tun.c:3520
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e5/0x260 kernel/task_work.c:246
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9e3/0x2650 kernel/exit.c:953
do_group_exit+0x229/0x2f0 kernel/exit.c:1095
get_signal+0x1398/0x14e0 kernel/signal.c:2933
arch_do_signal_or_restart+0xbc/0x760 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+0x57/0xb0 kernel/entry/common.c:218
do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fcdaa3560d7
Code: Unable to access opcode bytes at 0x7fcdaa3560ad.
RSP: 002b:00007ffc507b8ef0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: 0000000000000048 RBX: 000055556b2e1500 RCX: 00007fcdaa3560d7
RDX: 0000000000000048 RSI: 00007fcdab144670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc507b8f54 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fcdab144670 R15: 0000000000000000
net_ratelimit: 91997 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 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:0c, 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:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:33:4f:bf:55:96, 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:0c, vlan:0)
net_ratelimit: 115410 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 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:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:33:4f:bf:55:96, 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: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 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:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)