INFO: task syz.3.1353:11077 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1353 state:D stack:25400 pid:11077 tgid:11072 ppid:5820 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x14ea/0x5050 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
caif_exit_net+0x6a/0x4a0 net/caif/caif_dev.c:528
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x49f/0x940 net/core/net_namespace.c:252
setup_net+0x2f0/0x340 net/core/net_namespace.c:462
copy_net_ns+0x50e/0x730 net/core/net_namespace.c:581
create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0x11a/0x160 kernel/nsproxy.c:226
ksys_unshare+0x4f4/0x900 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3240
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f195139aeb9
RSP: 002b:00007f1952178028 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f1951616090 RCX: 00007f195139aeb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000
RBP: 00007f1951408c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1951616128 R14: 00007f1951616090 R15: 00007ffcd11ae7f8
Showing all locks held in the system:
1 lock held by kthreadd/2:
3 locks held by kworker/0:0/9:
#0: ffff88813fe55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813fe55948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc900000e7bc0 (reg_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900000e7bc0 (reg_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8f9ac188 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0xa50 net/wireless/reg.c:3189
3 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/31:
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:2/36:
3 locks held by kworker/1:1/43:
2 locks held by kworker/u8:3/44:
3 locks held by kworker/u8:4/60:
2 locks held by kworker/0:3/983:
8 locks held by kworker/0:1H/1077:
4 locks held by kworker/u8:5/1106:
6 locks held by kworker/u8:6/1158:
2 locks held by kworker/R-bat_e/3409:
2 locks held by klogd/5184:
2 locks held by udevd/5195:
2 locks held by dhcpcd/5489:
1 lock held by dhcpcd/5490:
2 locks held by crond/5564:
2 locks held by getty/5582:
#0: ffff88814d54f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000362b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5808:
1 lock held by udevd/5822:
#0: ffff888142781358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962
1 lock held by syz-executor/5828:
#0: ffff888030230308 (&xt[i].mutex){+.+.}-{4:4}, at: xt_find_table_lock+0x54/0x3e0 net/netfilter/x_tables.c:1243
2 locks held by syz-executor/5831:
7 locks held by kworker/u9:6/5834:
#0: ffff88802e094948 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88802e094948 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc9000438fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000438fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffff888059510ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331
#3: ffff8880595100c0 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0xa6f/0x1190 net/bluetooth/hci_sync.c:5703
#4: ffffffff8fb38968 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2128 [inline]
#4: ffffffff8fb38968 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x340 net/bluetooth/hci_conn.c:1336
#5: ffff888059f90338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 net/bluetooth/l2cap_core.c:1763
#6: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#6: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:956
3 locks held by kworker/1:4/5877:
2 locks held by kworker/0:4/5891:
3 locks held by kworker/0:6/5906:
#0: ffff88813fe56948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813fe56948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc90004f7fbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90004f7fbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8f9ac188 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa5/0xf40 net/wireless/reg.c:2453
4 locks held by kworker/u8:8/7148:
3 locks held by syz.1.1339/11010:
#0: ffff88804ada4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline]
#0: ffff88804ada4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2715
#1: ffff88804ada40c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5315
#2: ffffffff8fb38968 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline]
#2: ffffffff8fb38968 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637
2 locks held by syz.3.1353/11077:
#0: ffffffff8f99d890 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:577
#1: ffffffff8f9ac188 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x6a/0x4a0 net/caif/caif_dev.c:528
1 lock held by syz-executor/11206:
1 lock held by syz.4.1401/11252:
#0: ffffffff8f9ac188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f9ac188 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x722/0xbe0 net/core/rtnetlink.c:6964
5 locks held by kworker/u8:9/11255:
5 locks held by kworker/u8:10/11256:
4 locks held by kworker/u8:11/11257:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1077 Comm: kworker/0:1H Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: kblockd blk_mq_timeout_work
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d c4 3e 33 0c 48 89 de 5b e9 63 c5 5c 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d a8 38 2e 11 65 8b 15 c9 38 2e 11 81 e2 00 01 ff 00 74
RSP: 0018:ffffc90000006d98 EFLAGS: 00000297
RAX: ffffffff8a647969 RBX: 0000000000000000 RCX: 0000000000000100
RDX: ffff8880272b0000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc90000006eb0 R08: ffff8880272b0000 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000100 R12: 1ffff92000000dbc
R13: ffffffff8a646c00 R14: 0000000000000001 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881256f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555579a094e8 CR3: 0000000067b32000 CR4: 00000000003526f0
Call Trace:
NF_HOOK+0x369/0x3f0 include/linux/netfilter.h:317
br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:1167 [inline]
br_nf_forward_finish+0xa5e/0xe90 net/bridge/br_netfilter_hooks.c:662
NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:318
br_nf_forward_ip+0x7ef/0xa30 net/bridge/br_netfilter_hooks.c:716
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:316
__br_forward+0x397/0x540 net/bridge/br_forward.c:115
br_handle_frame_finish+0x1492/0x1b40 net/bridge/br_input.c:229
br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1
br_nf_pre_routing_finish_ipv6+0xa3a/0xd70 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:318 [inline]
br_nf_pre_routing_ipv6+0x374/0x6f0 net/bridge/br_netfilter_ipv6.c:184
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
br_handle_frame+0x1277/0x1510 net/bridge/br_input.c:442
__netif_receive_skb_core+0x98f/0x30a0 net/core/dev.c:6039
__netif_receive_skb_one_core net/core/dev.c:6150 [inline]
__netif_receive_skb net/core/dev.c:6265 [inline]
process_backlog+0x76d/0x1950 net/core/dev.c:6617
__napi_poll+0xae/0x340 net/core/dev.c:7681
napi_poll net/core/dev.c:7744 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7896
handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x801/0xb20 kernel/printk/printk.c:3289
Code: ff ff e8 b2 08 21 00 90 0f 0b 90 e9 85 fc ff ff e8 a4 08 21 00 e8 6f a0 f3 09 48 85 db 74 c0 e8 95 08 21 00 fb 48 8b 5c 24 08 <48> 8b 44 24 20 42 80 3c 20 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 36
RSP: 0018:ffffc900039feee0 EFLAGS: 00000293
RAX: ffffffff81a36ebb RBX: ffffc900039ff040 RCX: ffff8880272b0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900039feff0 R08: ffffffff8fef1b77 R09: 1ffffffff1fde36e
R10: dffffc0000000000 R11: fffffbfff1fde36f R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff8edeea00
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3359
vprintk_emit+0x485/0x560 kernel/printk/printk.c:2426
dev_vprintk_emit+0x355/0x420 drivers/base/core.c:4914
dev_printk_emit+0xee/0x140 drivers/base/core.c:4925
_dev_info+0x11e/0x180 drivers/base/core.c:4983
nbd_xmit_timeout+0x928/0xc70 drivers/block/nbd.c:520
blk_mq_rq_timed_out block/blk-mq.c:1653 [inline]
blk_mq_handle_expired+0x172/0x2c0 block/blk-mq.c:1721
bt_iter+0x2c9/0x390 block/blk-mq-tag.c:292
__sbitmap_for_each_set include/linux/sbitmap.h:269 [inline]
sbitmap_for_each_set+0x30e/0x5f0 include/linux/sbitmap.h:290
bt_for_each block/blk-mq-tag.c:324 [inline]
blk_mq_queue_tag_busy_iter+0x74b/0xbf0 block/blk-mq-tag.c:536
blk_mq_timeout_work+0x1bd/0x3f0 block/blk-mq.c:1763
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340
worker_thread+0xda6/0x1360 kernel/workqueue.c:3421
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246