INFO: task kworker/u8:2:60 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2 state:D stack:0 pid:60 tgid:60 ppid:2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
context_switch kernel/sched/core.c:6060 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7957 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7972
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
addrconf_dad_work+0xc8/0x1550 net/ipv6/addrconf.c:4234
process_one_work kernel/workqueue.c:3273 [inline]
process_scheduled_works+0x7f7/0x1060 kernel/workqueue.c:3354
worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435
kthread+0x2c7/0x360 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-executor:365 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:365 tgid:365 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6060 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7957 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7972
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
fib_net_exit_batch+0x24/0xa0 net/ipv4/fib_frontend.c:1652
ops_exit_list net/core/net_namespace.c:178 [inline]
setup_net+0x70f/0x9b0 net/core/net_namespace.c:388
copy_net_ns+0x4fc/0xa20 net/core/net_namespace.c:510
create_new_namespaces+0x390/0x6f0 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4f9/0x8f0 kernel/fork.c:3385
__do_sys_unshare kernel/fork.c:3468 [inline]
__se_sys_unshare kernel/fork.c:3466 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3466
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff02019f2e7
RSP: 002b:00007fff4e597e78 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007ff020425f40 RCX: 00007ff02019f2e7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007ff0204267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007fff4e5980b8 R15: 0000000000000000
INFO: task syz-executor:367 blocked for more than 125 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:367 tgid:367 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6060 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7957 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7972
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
fib_net_exit_batch+0x24/0xa0 net/ipv4/fib_frontend.c:1652
ops_exit_list net/core/net_namespace.c:178 [inline]
setup_net+0x70f/0x9b0 net/core/net_namespace.c:388
copy_net_ns+0x4fc/0xa20 net/core/net_namespace.c:510
create_new_namespaces+0x390/0x6f0 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4f9/0x8f0 kernel/fork.c:3385
__do_sys_unshare kernel/fork.c:3468 [inline]
__se_sys_unshare kernel/fork.c:3466 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3466
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f6845b9f2e7
RSP: 002b:00007fff1665f428 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f6845e25f40 RCX: 00007f6845b9f2e7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f6845e267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007fff1665f668 R15: 0000000000000000
INFO: task syz-executor:377 blocked for more than 126 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:377 tgid:377 ppid:1 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:6060 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7957 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7972
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676
netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x68a/0x700 net/socket.c:2216
__do_sys_sendto net/socket.c:2228 [inline]
__se_sys_sendto net/socket.c:2224 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2224
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5f3d359197
RSP: 002b:00007fff67d80900 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055557861f500 RCX: 00007f5f3d359197
RDX: 000000000000002c RSI: 00007f5f3e154670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff67d80964 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f5f3e154670 R15: 0000000000000000
INFO: task syz-executor:380 blocked for more than 128 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:380 tgid:380 ppid:1 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:6060 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7957 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7972
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676
netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x68a/0x700 net/socket.c:2216
__do_sys_sendto net/socket.c:2228 [inline]
__se_sys_sendto net/socket.c:2224 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2224
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f364e959197
RSP: 002b:00007fff53b08020 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055556e268500 RCX: 00007f364e959197
RDX: 000000000000002c RSI: 00007f364f754670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff53b08084 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f364f754670 R15: 0000000000000000
INFO: task syz-executor:381 blocked for more than 129 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:381 tgid:381 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6060 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7957 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7972
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8029
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676
netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x68a/0x700 net/socket.c:2216
__do_sys_sendto net/socket.c:2228 [inline]
__se_sys_sendto net/socket.c:2224 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2224
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fbc45359197
RSP: 002b:00007ffde4450580 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000555572ff6500 RCX: 00007fbc45359197
RDX: 0000000000000028 RSI: 00007fbc46154670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffde44505e4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fbc46154670 R15: 0000000000000000
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 89da86cd63dd77ed75a7a6b832383be384370f21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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+0xe45/0xf90 kernel/hung_task.c:423
kthread+0x2c7/0x360 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: 12 Comm: kworker/u8:0 Not tainted syzkaller #0 89da86cd63dd77ed75a7a6b832383be384370f21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: netns cleanup_net
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x23/0x70 kernel/kcov.c:217
Code: 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 48 8b 45 08 65 48 8b 0d ec 79 7d 7e 65 8b 15 ed 79 7d 7e 81 e2 00 01 ff 00 74 11 <81> fa 00 01 00 00 75 35 83 b9 ec 0b 00 00 00 74 2c 8b 91 c8 0b 00
RSP: 0018:ffffc90000230950 EFLAGS: 00000206
RAX: ffffffff84841134 RBX: ffff88811a6ce3c0 RCX: ffff888102652600
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000230950 R08: ffff888102652600 R09: 0000000000000002
R10: 000000000000a888 R11: 0000000000000100 R12: ffff88812fc701a0
R13: dffffc0000000000 R14: ffff88812fc701a0 R15: ffff88811a6ce3d0
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1efd755000 CR3: 000000010cf10000 CR4: 00000000003526b0
Call Trace:
__netif_receive_skb_core+0xaa4/0x3a70 net/core/dev.c:5649
__netif_receive_skb_one_core net/core/dev.c:5799 [inline]
__netif_receive_skb net/core/dev.c:5914 [inline]
process_backlog+0x40b/0xaf0 net/core/dev.c:6250
__napi_poll+0xcd/0x600 net/core/dev.c:6901
napi_poll net/core/dev.c:6970 [inline]
net_rx_action+0x5dc/0xd70 net/core/dev.c:7092
handle_softirqs+0x1aa/0x620 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_write_unlock_bh include/linux/rwlock_api_smp.h:281 [inline]
_raw_write_unlock_bh+0x33/0x70 kernel/locking/spinlock.c:366
pneigh_ifdown_and_unlock net/core/neighbour.c:872 [inline]
__neigh_ifdown+0x239/0x470 net/core/neighbour.c:448
neigh_ifdown+0x23/0x30 net/core/neighbour.c:465
arp_ifdown+0x20/0x30 net/ipv4/arp.c:1365
inetdev_destroy net/ipv4/devinet.c:347 [inline]
inetdev_event+0x9c3/0x1240 net/ipv4/devinet.c:1643
notifier_call_chain+0x106/0x2b0 kernel/notifier.c:93
raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:2074 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2112 [inline]
call_netdevice_notifiers net/core/dev.c:2126 [inline]
unregister_netdevice_many_notify+0xde1/0x1be0 net/core/dev.c:11533
unregister_netdevice_many net/core/dev.c:11595 [inline]
default_device_exit_batch+0x845/0x8d0 net/core/dev.c:12166
ops_exit_list net/core/net_namespace.c:178 [inline]
cleanup_net+0x741/0xc90 net/core/net_namespace.c:642
process_one_work kernel/workqueue.c:3273 [inline]
process_scheduled_works+0x7f7/0x1060 kernel/workqueue.c:3354
worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435
kthread+0x2c7/0x360 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: 132383 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 veth0_to_bridge with own address as source address (addr:0e:94:b7:d1:e8:6a, 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: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)