INFO: task kworker/u8:6:387 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:6 state:D stack:0 pid:387 tgid:387 ppid:2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
context_switch kernel/sched/core.c:6027 [inline]
__schedule+0x14ce/0x2100 kernel/sched/core.c:7894
__schedule_loop kernel/sched/core.c:7975 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7990
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8047
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bc0 kernel/locking/mutex.c:805
__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+0xce/0x1530 net/ipv6/addrconf.c:4234
process_one_work kernel/workqueue.c:3261 [inline]
process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342
worker_thread+0xc51/0x1370 kernel/workqueue.c:3423
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
INFO: task syz-executor:1443 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:1443 tgid:1443 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6027 [inline]
__schedule+0x14ce/0x2100 kernel/sched/core.c:7894
__schedule_loop kernel/sched/core.c:7975 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7990
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8047
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bc0 kernel/locking/mutex.c:805
__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
ip_tunnel_init_net+0x30c/0x890 net/ipv4/ip_tunnel.c:1145
erspan_init_net+0x2d/0x40 net/ipv4/ip_gre.c:1767
ops_init+0x1af/0x5d0 net/core/net_namespace.c:139
setup_net+0x227/0x9b0 net/core/net_namespace.c:356
copy_net_ns+0x512/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
ksys_unshare+0x503/0x8d0 kernel/fork.c:3374
__do_sys_unshare kernel/fork.c:3457 [inline]
__se_sys_unshare kernel/fork.c:3455 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3455
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: 0033:0x7f811199e127
RSP: 002b:00007ffd82f67048 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f8111c15f40 RCX: 00007f811199e127
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f8111c167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffd82f67288 R15: 0000000000000000
INFO: task syz-executor:1452 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:1452 tgid:1452 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6027 [inline]
__schedule+0x14ce/0x2100 kernel/sched/core.c:7894
__schedule_loop kernel/sched/core.c:7975 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7990
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8047
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bc0 kernel/locking/mutex.c:805
__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:6675
netlink_rcv_skb+0x259/0x4f0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c3/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x68d/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: 0033:0x7f6aebd57fd7
RSP: 002b:00007ffe2c83e9a0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055556ff52500 RCX: 00007f6aebd57fd7
RDX: 000000000000002c RSI: 00007f6aecb44670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffe2c83ea04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f6aecb44670 R15: 0000000000000000
INFO: task syz-executor:1454 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:1454 tgid:1454 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6027 [inline]
__schedule+0x14ce/0x2100 kernel/sched/core.c:7894
__schedule_loop kernel/sched/core.c:7975 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7990
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8047
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bc0 kernel/locking/mutex.c:805
__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
ip_tunnel_init_net+0x30c/0x890 net/ipv4/ip_tunnel.c:1145
erspan_init_net+0x2d/0x40 net/ipv4/ip_gre.c:1767
ops_init+0x1af/0x5d0 net/core/net_namespace.c:139
setup_net+0x227/0x9b0 net/core/net_namespace.c:356
copy_net_ns+0x512/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
ksys_unshare+0x503/0x8d0 kernel/fork.c:3374
__do_sys_unshare kernel/fork.c:3457 [inline]
__se_sys_unshare kernel/fork.c:3455 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3455
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: 0033:0x7f1a2119e127
RSP: 002b:00007ffc1a2b7d58 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f1a21415f40 RCX: 00007f1a2119e127
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f1a214167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffc1a2b7f98 R15: 0000000000000000
INFO: task syz-executor:1456 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:1456 tgid:1456 ppid:1 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:6027 [inline]
__schedule+0x14ce/0x2100 kernel/sched/core.c:7894
__schedule_loop kernel/sched/core.c:7975 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7990
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8047
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bc0 kernel/locking/mutex.c:805
__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:6675
netlink_rcv_skb+0x259/0x4f0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c3/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x68d/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: 0033:0x7fc6f3157fd7
RSP: 002b:00007ffc63fa6a10 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055556c57f500 RCX: 00007fc6f3157fd7
RDX: 0000000000000028 RSI: 00007fc6f3f44670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc63fa6a74 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc6f3f44670 R15: 0000000000000000
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 e2ac3d7d55ca18249f04a3621c430213fcbfc4af
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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+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: 514 Comm: kworker/u8:45 Not tainted syzkaller #0 e2ac3d7d55ca18249f04a3621c430213fcbfc4af
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: netns cleanup_net
RIP: 0010:get_stack_info_noinstr+0x2d/0x130 arch/x86/kernel/dumpstack_64.c:176
Code: 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 49 89 d6 49 89 f4 49 89 ff e8 21 01 00 00 b3 01 84 c0 75 0f 65 48 8b 05 b3 bb 5c 7a <49> 39 c4 74 14 31 db 89 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc
RSP: 0018:ffffc90000230120 EFLAGS: 00000246
RAX: ffff88813263a600 RBX: ffffc90000230201 RCX: ffffc90010170000
RDX: ffffc90000230208 RSI: ffffc90010178000 RDI: ffffc900002301f8
RBP: ffffc90000230148 R08: ffffc90000230200 R09: 0000000000000000
R10: ffffc90000230208 R11: fffff5200004604d R12: ffff88813263a600
R13: ffffc900002301f8 R14: ffffc90000230208 R15: ffffc900002301f8
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff2f4745000 CR3: 00000000074aa000 CR4: 00000000003526b0
Call Trace:
get_stack_info+0x3e/0x100 arch/x86/kernel/dumpstack_64.c:199
__unwind_start+0x20b/0x410 arch/x86/kernel/unwind_frame.c:405
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xf2/0x170 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:49 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565
unpoison_slab_object mm/kasan/common.c:321 [inline]
__kasan_slab_alloc+0x73/0x90 mm/kasan/common.c:347
kasan_slab_alloc include/linux/kasan.h:251 [inline]
slab_post_alloc_hook mm/slub.c:4202 [inline]
slab_alloc_node mm/slub.c:4251 [inline]
kmem_cache_alloc_noprof+0x1bf/0x410 mm/slub.c:4260
skb_clone+0x229/0x460 net/core/skbuff.c:2082
deliver_clone net/bridge/br_forward.c:125 [inline]
br_flood+0x661/0x730 net/bridge/br_forward.c:246
br_handle_frame_finish+0x11eb/0x17a0 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+0xfae/0x3ab0 net/core/dev.c:5695
__netif_receive_skb_one_core net/core/dev.c:5799 [inline]
__netif_receive_skb net/core/dev.c:5914 [inline]
process_backlog+0x3e5/0xad0 net/core/dev.c:6250
__napi_poll+0xd3/0x610 net/core/dev.c:6901
napi_poll net/core/dev.c:6970 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7092
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: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+0xe3f/0x1c30 net/core/dev.c:11533
unregister_netdevice_many net/core/dev.c:11595 [inline]
default_device_exit_batch+0x828/0x8c0 net/core/dev.c:12166
ops_exit_list net/core/net_namespace.c:178 [inline]
cleanup_net+0x744/0xc90 net/core/net_namespace.c:642
process_one_work kernel/workqueue.c:3261 [inline]
process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342
worker_thread+0xc51/0x1370 kernel/workqueue.c:3423
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