INFO: task syz-executor:3370 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:3370 tgid:3370 ppid:1 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_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
netdev_run_todo+0x118/0xce0 net/core/dev.c:10874
rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152
setup_net+0x5ea/0x9b0 net/core/net_namespace.c:384
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+0x502/0x880 kernel/fork.c:3356
__do_sys_unshare kernel/fork.c:3427 [inline]
__se_sys_unshare kernel/fork.c:3425 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3425
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: 0033:0x7f6ba7f9c1a7
RSP: 002b:00007ffe86ac7e68 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f6ba8215f40 RCX: 00007f6ba7f9c1a7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f6ba82167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffe86ac80a8 R15: 0000000000000000
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 8900111b7fef672e0561e32e4ed045c7fbde3c06
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: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 8900111b7fef672e0561e32e4ed045c7fbde3c06
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: netns cleanup_net
RIP: 0010:update_stack_state+0x298/0x4b0 arch/x86/kernel/unwind_frame.c:-1
Code: f7 49 c1 ef 03 48 b8 00 00 00 00 00 fc ff df 41 80 3c 07 00 74 08 4c 89 f7 e8 d4 96 9a 00 49 83 3e 00 74 2b 44 3b 6d ac 75 25 <48> 8b 45 a0 48 39 45 b0 73 1b 31 db 89 d8 48 81 c4 98 00 00 00 5b
RSP: 0018:ffffc9000022fef8 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffc90000230048 RCX: ffffc900000d7701
RDX: ffffc900000d7758 RSI: 1ffff9200004600a RDI: ffffc900002300a0
RBP: ffffc9000022ffb8 R08: ffffc90000230110 R09: ffffc90000230108
R10: 0000000000000014 R11: ffffffff8175cb90 R12: ffffc90000230048
R13: 0000000000000001 R14: ffffc90000230088 R15: 1ffff92000046011
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8de892b080 CR3: 000000010c3d2000 CR4: 00000000003526b0
Call Trace:
unwind_next_frame+0x3c1/0x750 arch/x86/kernel/unwind_frame.c:315
arch_stack_walk+0x138/0x170 arch/x86/kernel/stacktrace.c:25
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_free_info+0x4a/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:249 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2445 [inline]
slab_free mm/slub.c:4714 [inline]
kmem_cache_free+0x1bd/0x4f0 mm/slub.c:4821
kfree_skbmem net/core/skbuff.c:-1 [inline]
__kfree_skb+0x18f/0x210 net/core/skbuff.c:1203
consume_skb+0x65/0x1a0 net/core/skbuff.c:1434
netlink_broadcast_filtered+0x10e1/0x11f0 net/netlink/af_netlink.c:1530
nlmsg_multicast_filtered include/net/netlink.h:1125 [inline]
nlmsg_multicast include/net/netlink.h:1144 [inline]
nlmsg_notify+0xf1/0x1b0 net/netlink/af_netlink.c:2588
rtnl_notify+0x9e/0xd0 net/core/rtnetlink.c:786
fdb_notify+0xce/0x150 net/bridge/br_fdb.c:206
br_fdb_update+0x4b7/0x680 net/bridge/br_fdb.c:941
br_handle_frame_finish+0x3a3/0x1760 net/bridge/br_input.c:141
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]
unregister_netdevice_many_notify+0xe3f/0x1c30 net/core/dev.c:11495
unregister_netdevice_many+0x1d/0x30 net/core/dev.c:11557
cleanup_net+0x643/0xc90 net/core/net_namespace.c:637
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
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
net_ratelimit: 98079 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: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 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:62:ca:ad:38:57:9e, 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)
net_ratelimit: 123197 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:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:62:ca:ad:38:57:9e, 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)