INFO: task kworker/u8:3:53 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3 state:D stack:0 pid:53 tgid:53 ppid:2 flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134a/0x1dd0 kernel/sched/core.c:7842
__schedule_loop kernel/sched/core.c:7923 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7938
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7995
__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
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
linkwatch_event+0x12/0x60 net/core/link_watch.c:285
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d1/0x1020 kernel/workqueue.c:3319
worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
kthread+0x2c6/0x370 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:1017 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:1017 tgid:1017 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134a/0x1dd0 kernel/sched/core.c:7842
__schedule_loop kernel/sched/core.c:7923 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7938
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7995
__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
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
setup_net+0x51c/0x9b0 net/core/net_namespace.c:378
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:3354
__do_sys_unshare kernel/fork.c:3425 [inline]
__se_sys_unshare kernel/fork.c:3423 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3423
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: 0033:0x7f830599c1a7
RSP: 002b:00007ffd54f868d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f8305c15f40 RCX: 00007f830599c1a7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f8305c167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffd54f86b18 R15: 0000000000000000
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 fb5d95c0c59ed9c9506888f7deb6b66e4fe9f746
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+0x2c6/0x370 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: ksoftirqd/0 Not tainted syzkaller #0 fb5d95c0c59ed9c9506888f7deb6b66e4fe9f746
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__dev_queue_xmit+0x902/0x3690 net/core/dev.c:4482
Code: 00 00 48 8b 5c 24 20 48 85 db 0f 84 65 ff ff ff e8 e3 0c 0c fd 48 89 5c 24 20 48 83 c3 10 48 89 d8 48 c1 e8 03 42 80 3c 28 00 <74> 08 48 89 df e8 84 d3 63 fd 4c 8b 23 0f 1f 44 00 00 e8 b7 0c 0c
RSP: 0018:ffffc90000117100 EFLAGS: 00000246
RAX: 1ffff110216d3302 RBX: ffff88810b699810 RCX: ffff888103653900
RDX: 0000000000000100 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffc900001173d0 R08: ffff88812ab71da3 R09: 1ffff1102556e3b4
R10: dffffc0000000000 R11: ffffed102556e3b5 R12: 1ffff1102a69c85b
R13: dffffc0000000000 R14: ffff888131538000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ed9aa2af8 CR3: 000000010c360000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 00000000000000d8 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
dev_queue_xmit include/linux/netdevice.h:3141 [inline]
br_dev_queue_push_xmit+0x55c/0x700 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]
br_flood+0x67e/0x730 net/bridge/br_forward.c:246
br_handle_frame_finish+0x12f9/0x1760 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+0xfb1/0x3ab0 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+0xd0/0x610 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+0x1ad/0x630 kernel/softirq.c:621
run_ksoftirqd+0x20/0x30 kernel/softirq.c:999
smpboot_thread_fn+0x492/0x8b0 kernel/smpboot.c:164
kthread+0x2c6/0x370 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: 98582 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:e2:f3:1c:c7:91:5e, 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:e2:f3:1c:c7:91:5e, 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:e2:f3:1c:c7:91:5e, 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:e2:f3:1c:c7:91:5e, 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:e2:f3:1c:c7:91:5e, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)