INFO: task syz.0.1544:5099 blocked for more than 125 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1544 state:D stack:0 pid:5099 tgid:5098 ppid:3473 flags:0x00004006
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
request_wait_answer fs/fuse/dev.c:477 [inline]
__fuse_request_send fs/fuse/dev.c:493 [inline]
__fuse_simple_request+0xdee/0x1b10 fs/fuse/dev.c:588
fuse_simple_request fs/fuse/fuse_i.h:1248 [inline]
fuse_flush+0xad9/0x2020 fs/fuse/file.c:602
filp_flush fs/open.c:1552 [inline]
filp_close+0xc0/0x160 fs/open.c:1565
close_files fs/file.c:425 [inline]
put_files_struct+0x1b5/0x330 fs/file.c:440
exit_files+0x84/0xa0 fs/file.c:457
do_exit+0x9ac/0x2650 kernel/exit.c:948
do_group_exit+0x229/0x2f0 kernel/exit.c:1095
get_signal+0x1398/0x14e0 kernel/signal.c:2933
arch_do_signal_or_restart+0xbc/0x760 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: 0033:0x7fd1b719a94b
RSP: 002b:00007fd1b7f8cf00 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 0000000000000008 RCX: 00007fd1b719a94b
RDX: 00007fd1b7f8dfd0 RSI: 0000000080085502 RDI: 0000000000000008
RBP: 00007fd1b7f8dfd0 R08: 0000000000000024 R09: 00007fd1b7f8cfc8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 0000000000000024 R15: 00007fd1b72092c1
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 1299f57362d1784c0f26c9767fc5423e1fa623f7
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5142 Comm: syz-executor Not tainted syzkaller #0 1299f57362d1784c0f26c9767fc5423e1fa623f7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:dev_sw_netstats_tx_add include/linux/netdevice.h:2810 [inline]
RIP: 0010:veth_xmit+0x732/0xb20 drivers/net/veth.c:378
Code: 74 3b 13 fe eb 7d e8 6d 3b 13 fe 65 48 8b 1d 0d c5 8d 7c 4c 8b 75 c8 49 81 c6 a0 00 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 f7 e8 04 02 6b fe 49 8b 06 48 8b 8d 78 ff ff ff 48 01
RSP: 0018:ffffc90000230138 EFLAGS: 00000246
RAX: 1ffff11023272014 RBX: ffff8881f6f00000 RCX: ffff8881177e5f00
RDX: 0000000000000100 RSI: ffffffff879b8e80 RDI: 0000000000000000
RBP: ffffc900002301c0 R08: ffff8881177e5f00 R09: 0000000000000003
R10: 0000000000000010 R11: 0000000000000100 R12: dffffc0000000000
R13: ffff88811950a380 R14: ffff8881193900a0 R15: 0000000000000000
FS: 00005555661c1500(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000016038 CR3: 0000000119312000 CR4: 00000000003526b0
Call Trace:
__netdev_start_xmit include/linux/netdevice.h:4975 [inline]
netdev_start_xmit include/linux/netdevice.h:4984 [inline]
xmit_one net/core/dev.c:3668 [inline]
dev_hard_start_xmit+0x21b/0x760 net/core/dev.c:3684
__dev_queue_xmit+0x1905/0x3690 net/core/dev.c:4520
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+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+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
__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]
tipc_node_pre_cleanup_net+0x1cb/0x260 net/tipc/node.c:3162
tipc_pernet_pre_exit+0x19/0x30 net/tipc/core.c:127
ops_pre_exit_list net/core/net_namespace.c:163 [inline]
setup_net+0x48c/0x9b0 net/core/net_namespace.c:373
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: 0033:0x7ff9ee39bfa7
Code: 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcef2ba968 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007ff9ee615f40 RCX: 00007ff9ee39bfa7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007ff9ee6167b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffcef2baba8 R15: 0000000000000000
net_ratelimit: 385495 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 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)
net_ratelimit: 422958 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 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 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)