INFO: task syz-executor:294 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:294 tgid:294 ppid:1 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:6052 [inline]
__schedule+0x1496/0x20b0 kernel/sched/core.c:7865
__schedule_loop kernel/sched/core.c:7942 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7957
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+0x368/0x650 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
rcu_barrier+0x45a/0x580 kernel/rcu/tree.c:4657
netdev_run_todo+0x118/0xce0 net/core/dev.c:10912
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+0x208/0xa30 fs/file_table.c:447
____fput+0x20/0x30 fs/file_table.c:475
task_work_run+0x1e8/0x260 kernel/task_work.c:246
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xa46/0x2850 kernel/exit.c:955
do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
get_signal+0x134c/0x1490 kernel/signal.c:2933
arch_do_signal_or_restart+0xbc/0x700 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: 0033:0x7f9724758fd7
RSP: 002b:00007ffc64663020 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 000055558d1d5500 RCX: 00007f9724758fd7
RDX: 0000000040000000 RSI: 00007ffc646630ac RDI: ffffffffffffffff
RBP: 00007ffc646630ac R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000006a
R13: 000055558d1e88e0 R14: 000000000001a2ac R15: 00007ffc64663100
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 991092e6aacd45c89fe3e25b50ff7d10cec51463
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+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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: rcuop/1 Not tainted syzkaller #0 991092e6aacd45c89fe3e25b50ff7d10cec51463
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:update_stack_state+0xba/0x4d0 arch/x86/kernel/unwind_frame.c:-1
Code: 1c 8b 9b 00 49 8b 06 48 83 c0 10 48 89 45 a8 4c 8b 75 98 44 89 f0 83 e0 01 48 f7 d8 4c 89 f2 48 83 e2 fe 48 21 d0 48 89 45 c8 <48> 89 55 88 74 26 4d 8d 75 35 4c 89 f0 48 c1 e8 03 42 0f b6 04 38
RSP: 0018:ffffc900000070a8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc90000007228 RCX: ffffc900000072b0
RDX: ffffc900000072b0 RSI: ffffc900000072b0 RDI: ffffc90000007280
RBP: ffffc90000007158 R08: ffffc90000007200 R09: 0000000000000000
R10: ffffc90000007228 R11: fffff52000000e51 R12: ffffc90000007218
R13: ffffc90000007228 R14: ffffc900000072b0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7cf3822060 CR3: 000000011ec3c000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000007000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
unwind_next_frame+0x39e/0x6b0 arch/x86/kernel/unwind_frame.c:315
__unwind_start+0x340/0x400 arch/x86/kernel/unwind_frame.c:417
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+0x3a/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+0x21d/0x470 net/core/skbuff.c:2079
deliver_clone net/bridge/br_forward.c:125 [inline]
br_flood+0x650/0x720 net/bridge/br_forward.c:246
br_handle_frame_finish+0x1157/0x1620 net/bridge/br_input.c:215
nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
br_handle_frame+0x5a5/0xba0 net/bridge/br_input.c:424
__netif_receive_skb_core+0xfc1/0x3a70 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+0x40b/0xaf0 net/core/dev.c:6250
__napi_poll+0xd0/0x600 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
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_do_batch+0x590/0xcb0 kernel/rcu/tree.c:2594
nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
rcu_nocb_cb_kthread+0x533/0xb60 kernel/rcu/tree_nocb.h:957
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: 285016 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 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)
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 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)
net_ratelimit: 288481 callbacks suppressed
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)
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 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)