INFO: task syz.2.2952:27258 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2952 state:D stack:26120 pid:27258 tgid:27257 ppid:23227 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5258 [inline] __schedule+0x150e/0x5070 kernel/sched/core.c:6866 __schedule_loop kernel/sched/core.c:6948 [inline] schedule+0x165/0x360 kernel/sched/core.c:6963 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7020 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1590 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+0x18f/0x1d0 net/socket.c:737 __sock_sendmsg net/socket.c:752 [inline] ____sys_sendmsg+0x577/0x880 net/socket.c:2610 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2664 __sys_sendmsg net/socket.c:2696 [inline] __do_sys_sendmsg net/socket.c:2701 [inline] __se_sys_sendmsg net/socket.c:2699 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2699 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: 0033:0x7fd93e18f749 RSP: 002b:00007fd93c3f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd93e3e5fa0 RCX: 00007fd93e18f749 RDX: 0000000000008004 RSI: 0000200000000180 RDI: 0000000000000009 RBP: 00007fd93e213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd93e3e6038 R14: 00007fd93e3e5fa0 R15: 00007ffcbfc4c168 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df41b20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df41b20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df41b20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:2/36: 4 locks held by kworker/u8:13/4542: #0: ffff88801b2df148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000d3c7b80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8f3051d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670 #3: ffffffff8f312808 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1c/0x200 drivers/net/wireguard/device.c:419 2 locks held by getty/5583: #0: ffff88814e0050a0 (&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 1 lock held by syz-executor/23807: 2 locks held by syz.6.2870/26979: #0: ffffffff8f37a3f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e237c28 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1880 2 locks held by syz.2.2952/27258: #0: ffffffff8f37a3f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e237c28 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1590 2 locks held by syz-executor/31101: #0: ffffffff8f312808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f312808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f312808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071 #1: ffff888025d90d48 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2786 [inline] #1: ffff888025d90d48 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff888025d90d48 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: do_setlink+0x388/0x41c0 net/core/rtnetlink.c:3068 1 lock held by syz.0.3750/31609: #0: ffff8880779a6cd8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11497 2 locks held by syz.0.3750/31686: #0: ffffffff9a44ae18 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff9a44ae18 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_batch net/netfilter/nfnetlink.c:394 [inline] #0: ffffffff9a44ae18 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:649 [inline] #0: ffffffff9a44ae18 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv+0x63b/0x2590 net/netfilter/nfnetlink.c:667 #1: ffff8880779a6cd8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11497 3 locks held by syz.9.3756/31638: #0: ffff88803f537508 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88803f537508 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x89/0x250 net/socket.c:665 #1: ffffffff8f378830 ((netlink_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:379 #2: ffff88807ca8ccd8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nft_rcv_nl_event+0x116/0x640 net/netfilter/nf_tables_api.c:12085 2 locks held by syz.9.3756/31639: #0: ffffffff8ddfcc48 (sched_core_mutex){+.+.}-{4:4}, at: sched_core_get+0x52/0x170 kernel/sched/core.c:485 #1: ffffffff8df47678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8df47678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956 1 lock held by syz.5.3753/31688: #0: ffffffff8ddfcc48 (sched_core_mutex){+.+.}-{4:4}, at: sched_core_get+0x52/0x170 kernel/sched/core.c:485 1 lock held by syz.5.3753/31689: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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: 31101 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_cmp1+0x8/0x90 kernel/kcov.c:276 Code: cc cc cc cc cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 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 14 25 08 e0 7e 92 65 8b 0d 38 2e bd 10 81 e1 00 01 ff 00 RSP: 0018:ffffc9000cad6088 EFLAGS: 00000246 RAX: ffffffff8b57db0a RBX: 0000000000000008 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000075 RDI: 000000000000006c RBP: ffffffff8b6bb9e3 R08: ffff8880255b8000 R09: 0000000000000002 R10: 0000000000000025 R11: 0000000000000000 R12: 000000000000006c R13: 0000000000000075 R14: 000000000000006c R15: 0000000000000008 FS: 000055556eedc500(0000) GS:ffff888125e32000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f28383b7198 CR3: 000000005e7e6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: fffffffffffffffc DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: format_decode+0x4ca/0xe10 lib/vsprintf.c:2780 vsnprintf+0x102/0xee0 lib/vsprintf.c:2889 sprintf+0xd9/0x120 lib/vsprintf.c:3110 print_time kernel/printk/printk.c:1357 [inline] info_print_prefix+0x155/0x310 kernel/printk/printk.c:1383 record_print_text+0x154/0x420 kernel/printk/printk.c:1432 printk_get_next_message+0x26d/0x7b0 kernel/printk/printk.c:3018 console_emit_next_record kernel/printk/printk.c:3083 [inline] console_flush_one_record kernel/printk/printk.c:3215 [inline] console_flush_all+0x514/0xb60 kernel/printk/printk.c:3289 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xbb/0x190 kernel/printk/printk.c:3359 vprintk_emit+0x4f8/0x5f0 kernel/printk/printk.c:2426 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925 __netdev_printk+0x3e1/0x480 net/core/dev.c:12920 netdev_info+0x10a/0x160 net/core/dev.c:12975 netif_change_name+0x863/0x930 net/core/dev.c:1466 do_setlink+0x9f6/0x41c0 net/core/rtnetlink.c:3138 rtnl_changelink net/core/rtnetlink.c:3776 [inline] __rtnl_newlink net/core/rtnetlink.c:3935 [inline] rtnl_newlink+0x161c/0x1c90 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 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+0x18f/0x1d0 net/socket.c:737 __sock_sendmsg net/socket.c:752 [inline] __sys_sendto+0x3ce/0x540 net/socket.c:2221 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2224 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: 0033:0x7fb13fd915dc Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b RSP: 002b:00007ffe3bcad6e0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fb140b135c0 RCX: 00007fb13fd915dc RDX: 0000000000000030 RSI: 00007fb140b13610 RDI: 0000000000000006 RBP: 0000000000000000 R08: 00007ffe3bcad734 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000006 R13: 0000000000000000 R14: 00007fb140b13610 R15: 0000000000000000