INFO: task syz.8.7463:3452 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.7463 state:D stack:25680 pid:3452 tgid:3451 ppid:27599 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
nfsd_nl_rpc_status_get_dumpit+0xdf/0x1290 fs/nfsd/nfsctl.c:1516
genl_dumpit+0x10b/0x1b0 net/netlink/genetlink.c:1027
netlink_dump+0x6e4/0xe90 net/netlink/af_netlink.c:2327
__netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2442
genl_family_rcv_msg_dumpit+0x1e7/0x2c0 net/netlink/genetlink.c:1076
genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline]
genl_rcv_msg+0x5da/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:729
____sys_sendmsg+0x505/0x830 net/socket.c:2614
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
__sys_sendmsg net/socket.c:2700 [inline]
__do_sys_sendmsg net/socket.c:2705 [inline]
__se_sys_sendmsg net/socket.c:2703 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efd5658eec9
RSP: 002b:00007efd57412038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efd567e5fa0 RCX: 00007efd5658eec9
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000004
RBP: 00007efd56611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efd567e6038 R14: 00007efd567e5fa0 R15: 00007ffc56246628
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5628:
#0: ffff88803028d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/u8:13/6986:
#0: ffff88814caa0948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88814caa0948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90003a3fbc0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90003a3fbc0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4734
2 locks held by syz.1.7328/2951:
#0: ffffffff8f5a08d0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919
3 locks held by syz.8.7463/3452:
#0: ffffffff8f5a08d0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffff888062b1d6e0 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2406
#2: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdf/0x1290 fs/nfsd/nfsctl.c:1516
2 locks held by syz.9.7523/3702:
#0: ffffffff8f5a08d0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919
1 lock held by ipvs-e:489:0/4004:
2 locks held by syz.5.7599/4061:
#0: ffffffff8f5a08d0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919
2 locks held by syz.6.7872/5201:
#0: ffffffff8f52df10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
#1: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:172 [inline]
#1: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990 net/core/net_namespace.c:247
2 locks held by syz.3.7875/5221:
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
#1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
2 locks held by syz.7.7876/5229:
#0: ffffffff8f52df10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
#1: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x80/0x210 net/ipv4/nexthop.c:3971
1 lock held by syz.2.7878/5237:
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x37a/0x1df0 drivers/net/tun.c:3078
1 lock held by syz.4.7883/5255:
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x346/0x700 net/core/rtnetlink.c:3555
1 lock held by syz-executor/5258:
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
1 lock held by syz-executor/5260:
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f53adc8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978
=============================================
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 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16166 Comm: ipvs-e:86:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:bstr_printf+0x374/0xb70 lib/vsprintf.c:3309
Code: 49 89 c6 e8 8e 5f 4f f6 4d 29 e6 48 89 df 4c 89 f6 e8 e0 61 4f f6 4c 39 f3 4d 0f 4f ee 49 be 00 00 00 00 00 fc ff df 49 63 d5 <4c> 89 e7 4c 89 fe e8 c1 e4 b2 f6 e9 af 00 00 00 e8 57 5f 4f f6 48
RSP: 0018:ffffc9000b2b7250 EFLAGS: 00000083
RAX: ffffffff8b704f40 RBX: 0000000000000002 RCX: ffff88806b4a3c00
RDX: 0000000000000002 RSI: 0000000000000400 RDI: 0000000000000002
RBP: ffffc9000b2b73ea R08: ffff88806b4a3c00 R09: 0000000000000009
R10: 0000000000000008 R11: 0000000000000000 R12: ffff8880b8631700
R13: 0000000000000002 R14: dffffc0000000000 R15: ffffc9000b2b73e8
FS: 0000000000000000(0000) GS:ffff888125c39000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563c7b80afb0 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
____bpf_trace_printk kernel/trace/bpf_trace.c:378 [inline]
bpf_trace_printk+0x10e/0x190 kernel/trace/bpf_trace.c:363
bpf_prog_9e1c00255e17e72e+0x39/0x3f
bpf_dispatcher_nop_func include/linux/bpf.h:1335 [inline]
__bpf_prog_run include/linux/filter.h:718 [inline]
bpf_prog_run include/linux/filter.h:725 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
bpf_trace_run1+0x27c/0x4b0 kernel/trace/bpf_trace.c:2297
__bpf_trace_rcu_utilization+0xa1/0xf0 include/trace/events/rcu.h:27
__traceiter_rcu_utilization+0x7a/0xb0 include/trace/events/rcu.h:27
__do_trace_rcu_utilization include/trace/events/rcu.h:27 [inline]
trace_rcu_utilization+0x1ad/0x1d0 include/trace/events/rcu.h:27
rcu_note_context_switch+0xc9/0x1140 kernel/rcu/tree_plugin.h:330
__schedule+0x35d/0x4cc0 kernel/sched/core.c:6846
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
ip_vs_estimation_kthread+0x2a2a/0x3a00 net/netfilter/ipvs/ip_vs_est.c:209
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245