INFO: task syz.1.2022:13408 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2022 state:D stack:26232 pid:13408 tgid:13405 ppid:5830 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fd0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 nfsd_nl_threads_get_doit+0x1b6/0x6f0 fs/nfsd/nfsctl.c:1678 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x820 net/socket.c:2592 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f95cc58f749 RSP: 002b:00007f95cd395038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f95cc7e5fa0 RCX: 00007f95cc58f749 RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000004 RBP: 00007f95cc613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f95cc7e6038 R14: 00007f95cc7e5fa0 R15: 00007ffcbb012378 Showing all locks held in the system: 2 locks held by kworker/0:0/9: 1 lock held by khungtaskd/31: #0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5589: #0: ffff88814d1e10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 6 locks held by kworker/0:7/9463: 3 locks held by kworker/0:12/9469: 2 locks held by kworker/0:13/9470: 2 locks held by kworker/0:20/9481: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by kworker/0:22/9483: 2 locks held by syz.3.1913/13039: #0: ffffffff8f379db0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e237968 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1886 2 locks held by syz.1.2022/13408: #0: ffffffff8f379db0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e237968 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1b6/0x6f0 fs/nfsd/nfsctl.c:1678 2 locks held by syz.0.2222/14184: #0: ffffffff8f379db0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e237968 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_get_doit+0x10a/0x5e0 fs/nfsd/nfsctl.c:2036 ============================================= 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 10/25/2025 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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 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: 9469 Comm: kworker/0:12 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: wg-kex-wg1 wg_packet_handshake_receive_worker RIP: 0010:skb_is_decrypted include/linux/skbuff.h:1707 [inline] RIP: 0010:sk_validate_xmit_skb net/core/dev.c:3959 [inline] RIP: 0010:validate_xmit_skb+0x813/0x1440 net/core/dev.c:4011 Code: 0f b6 04 28 84 c0 0f 85 3c 08 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 4e 08 00 00 8b 1a 89 de 81 e6 00 00 00 04 <31> ff e8 c6 70 89 f8 81 e3 00 00 00 04 0f 85 8f 05 00 00 e8 75 6c RSP: 0018:ffffc90000006f40 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000008000000 RCX: ffff8880290fdb80 RDX: ffff88807585e441 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000081 R08: ffff8880290fdb80 R09: 0000000000000002 R10: 0000000000004888 R11: 0000000000000100 R12: 0000212e4fdd00e9 R13: dffffc0000000000 R14: ffff88807585e3c0 R15: ffff88807585e400 FS: 0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f939348df98 CR3: 000000000dd3a000 CR4: 00000000003526f0 Call Trace: __dev_queue_xmit+0x10e2/0x3100 net/core/dev.c:4824 dev_queue_xmit include/linux/netdevice.h:3381 [inline] br_dev_queue_push_xmit+0x6c5/0x890 net/bridge/br_forward.c:53 NF_HOOK+0x320/0x3c0 include/linux/netfilter.h:318 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 NF_HOOK+0x320/0x3c0 include/linux/netfilter.h:318 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 br_handle_frame_finish+0x15a3/0x1c90 net/bridge/br_input.c:229 nf_hook_bridge_pre net/bridge/br_input.c:313 [inline] br_handle_frame+0xb75/0x14f0 net/bridge/br_input.c:442 __netif_receive_skb_core+0x95f/0x2f90 net/core/dev.c:6039 __netif_receive_skb_one_core net/core/dev.c:6150 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6265 process_backlog+0x54f/0x1340 net/core/dev.c:6617 __napi_poll+0xae/0x320 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x64a/0xe00 net/core/dev.c:7896 handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:936 [inline] wg_pubkey_hashtable_lookup+0x316/0x360 drivers/net/wireguard/peerlookup.c:69 wg_noise_handshake_consume_initiation+0x358/0x900 drivers/net/wireguard/noise.c:617 wg_receive_handshake_packet drivers/net/wireguard/receive.c:144 [inline] wg_packet_handshake_receive_worker+0x5ee/0xfc0 drivers/net/wireguard/receive.c:213 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 net_ratelimit: 37558 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)