INFO: task syz.7.7977:32641 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.7977 state:D stack:25920 pid:32641 tgid:32639 ppid:31524 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 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 nfnl_lock net/netfilter/nfnetlink.c:98 [inline] nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 nfnetlink_rcv+0x282/0x2590 net/netfilter/nfnetlink.c:669 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+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f16fbb8f749 RSP: 002b:00007f16fca18038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f16fbde5fa0 RCX: 00007f16fbb8f749 RDX: 0000000020004000 RSI: 00002000000003c0 RDI: 0000000000000007 RBP: 00007f16fbc13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f16fbde6038 R14: 00007f16fbde5fa0 R15: 00007fff71ea1d98 INFO: task syz.6.8006:32732 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.8006 state:D stack:26144 pid:32732 tgid:32731 ppid:27578 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 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 nfnl_lock net/netfilter/nfnetlink.c:98 [inline] nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 nfnetlink_rcv+0x282/0x2590 net/netfilter/nfnetlink.c:669 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+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb15758f749 RSP: 002b:00007fb158394038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fb1577e5fa0 RCX: 00007fb15758f749 RDX: 0000000000000000 RSI: 0000200000000440 RDI: 0000000000000003 RBP: 00007fb157613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb1577e6038 R14: 00007fb1577e5fa0 R15: 00007ffe8182bba8 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5589: #0: ffff8880303230a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:12/11807: #0: ffff88813ff15948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff15948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000f3e7b80 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000f3e7b80 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956 1 lock held by syz.3.5726/23908: 1 lock held by syz.7.7977/32641: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.6.8006/32732: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.2.8071/522: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.8.8144/872: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.1.8174/1022: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.5.8204/1170: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.5.8204/1172: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.4.8224/1263: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.0.8245/1350: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.9.8247/1366: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: ip_set_nfnl_get_byindex+0x67/0x230 net/netfilter/ipset/ip_set_core.c:909 3 locks held by kworker/u8:3/1593: #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: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x8ee/0xf30 kernel/time/timer.c:1117 1 lock held by syz.6.8310/1664: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.3.8329/1734: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: ip_set_nfnl_get_byindex+0x67/0x230 net/netfilter/ipset/ip_set_core.c:909 1 lock held by syz.7.8330/1738: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.2.8280/1744: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.8.8380/1962: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.8.8380/1964: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.8.8380/1966: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.4.8370/2076: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 3 locks held by syz-executor/2096: #0: ffff88806f638ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff88806f638ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff88806f6380c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8f483848 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff8f483848 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637 1 lock held by syz.0.8410/2168: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 1 lock held by syz.1.8441/2297: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 4 locks held by syz-executor/2306: #0: ffff8881807f8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff8881807f8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff8881807f80c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8f483848 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff8f483848 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637 #3: ffff888050708338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 net/bluetooth/l2cap_core.c:1763 1 lock held by syz.5.8443/2309: #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99dcd2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 2 locks held by syz.6.8459/2419: #0: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 #1: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:956 3 locks held by syz-executor/2423: #0: ffff88819279cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff88819279cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5b0 net/bluetooth/hci_core.c:2715 #1: ffff88819279c0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x1100 net/bluetooth/hci_sync.c:5314 #2: ffffffff8f483848 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff8f483848 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2637 ============================================= 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+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] __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+0x599/0xb30 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: 2180 Comm: kworker/u8:14 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3802 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline] RIP: 0010:__lock_acquire+0xc4d/0x2cf0 kernel/locking/lockdep.c:5237 Code: 48 ff cb f7 c1 00 60 00 00 74 c3 e9 90 00 00 00 48 c7 c7 30 1d e1 8d 4c 89 fe e8 be 8f 29 03 48 8b 54 24 18 eb c3 48 8b 48 18 <48> 39 e9 0f 84 b9 00 00 00 48 8b 40 08 48 85 c0 0f 84 ca fe ff ff RSP: 0018:ffffc9000b667750 EFLAGS: 00000046 RAX: ffffffff93b25230 RBX: 000000000003e52e RCX: cd26970529f238f1 RDX: 0000000073d3d700 RSI: 00000000e45bdd7b RDI: ffff88802e4e5b80 RBP: cd26970529f238f1 R08: ffffffff86ea12cc R09: ffff888028c425f8 R10: ffffc9000b667820 R11: fffff520016ccf0c R12: ffff88802e4e6750 R13: ffff88802e4e6750 R14: ffff88802e4e5b80 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff888125e35000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055aa49220000 CR3: 000000000dd3a000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:886 [inline] nsim_dev_trap_report_work+0x72c/0xb80 drivers/net/netdevsim/dev.c:921 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+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246