INFO: task kworker/u8:41:7216 blocked for more than 143 seconds.
Tainted: G U W L XTNJ syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:41 state:D stack:23544 pid:7216 tgid:7216 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4033
rxrpc_destroy_all_connections+0xed/0x440 net/rxrpc/conn_object.c:477
rxrpc_exit_net+0x7b/0xc0 net/rxrpc/net_ns.c:113
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252
cleanup_net+0x41b/0x830 net/core/net_namespace.c:696
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task syz.3.3607:21019 blocked for more than 144 seconds.
Tainted: G U W L XTNJ syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.3607 state:D stack:27496 pid:21019 tgid:21018 ppid:16267 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4033
rxrpc_release_sock net/rxrpc/af_rxrpc.c:965 [inline]
rxrpc_release+0x2a7/0x6a0 net/rxrpc/af_rxrpc.c:996
__sock_release net/socket.c:662 [inline]
sock_release+0x91/0x1d0 net/socket.c:690
afs_open_socket+0x334/0x400 fs/afs/rxrpc.c:117
afs_net_init+0x825/0xb00 fs/afs/main.c:116
ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
setup_net+0x11d/0x3a0 net/core/net_namespace.c:446
copy_net_ns+0x351/0x7c0 net/core/net_namespace.c:581
create_new_namespaces+0x3ea/0xab0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:226
ksys_unshare+0x45b/0xa40 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3240
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbbed18f7c9
RSP: 002b:00007fbbedf8d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fbbed3e5fa0 RCX: 00007fbbed18f7c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000080
RBP: 00007fbbed213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbbed3e6038 R14: 00007fbbed3e5fa0 R15: 00007ffdeccaae28
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c9520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/0:11/7057:
#0: ffff8880b843add8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843add8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
#1: ffff8880b8424608 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424608 (psi_seq){-.-.}-{0:0}, at: __schedule+0x19b1/0x6150 kernel/sched/core.c:6857
#2: ffff8880b84262d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x127/0x1d0 kernel/time/timer.c:1004
3 locks held by kworker/u8:41/7216:
#0: ffff88801badf148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000bb77c90 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff9012ecd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x830 net/core/net_namespace.c:670
2 locks held by getty/19709:
#0: ffff8880354b00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000c5e72f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211
3 locks held by kworker/u11:7/20996:
#0: ffff88813ff69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90004a17c90 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303
1 lock held by syz.3.3607/21019:
#0: ffffffff9012ecd0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
1 lock held by syz.1.3636/21195:
#0: ffff88805903e3c8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88805903e3c8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
2 locks held by syz-executor/21394:
#0: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
#1: ffffffff8e3d4c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.2.3740/21731:
#0: ffffffff9012ecd0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
1 lock held by syz.4.3807/22007:
1 lock held by syz.5.3936/22546:
#0: ffffffff9012ecd0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
1 lock held by syz.7.4073/23088:
#0: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
1 lock held by syz.8.4077/23107:
#0: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff901454a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G U W L XTNJ syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [W]=WARN, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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: 7057 Comm: kworker/0:11 Tainted: G U W L XTNJ syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [W]=WARN, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events free_obj_work
RIP: 0010:stack_trace_consume_entry+0x26/0x170 kernel/stacktrace.c:86
Code: 90 90 90 90 f3 0f 1e fa 48 b8 00 00 00 00 00 fc ff df 55 53 48 89 fb 48 83 c7 10 48 89 fa 48 c1 ea 03 48 83 ec 08 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e e7 00 00 00 48 8d 7b 08 8b 6b 10 48 b8 00
RSP: 0018:ffffc9000bb176c0 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffffc9000bb177a0 RCX: ffffc9000bb17778
RDX: 1ffff92001762ef6 RSI: ffffffff81a8fc9e RDI: ffffc9000bb177b0
RBP: ffffc9000bb17770 R08: 0000000000000001 R09: 0000000077c2901c
R10: 0000000000000002 R11: 000000000000633f R12: ffffffff81a8f9f0
R13: ffffc9000bb177a0 R14: 0000000000000000 R15: ffff88802d650000
FS: 0000000000000000(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cee1db5000 CR3: 000000007d1ca000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x88/0x100 arch/x86/kernel/stacktrace.c:27
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6670 [inline]
kmem_cache_free+0x2d8/0x770 mm/slub.c:6781
free_object_list.isra.0+0xf8/0x2a0 lib/debugobjects.c:326
free_obj_work+0x19d/0x3d0 lib/debugobjects.c:513
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246