INFO: task syz-executor:5870 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:23368 pid:5870 tgid:5870 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 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+0x81b/0x1060 kernel/locking/mutex.c:760 nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 nfsd_umount+0x48/0xe0 fs/nfsd/nfsctl.c:1386 deactivate_locked_super+0xbe/0x1a0 fs/super.c:474 deactivate_super fs/super.c:507 [inline] deactivate_super+0xde/0x100 fs/super.c:503 cleanup_mnt+0x225/0x450 fs/namespace.c:1375 task_work_run+0x14d/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9d3778ff17 RSP: 002b:00007ffdb9115768 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f9d37811c05 RCX: 00007f9d3778ff17 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdb91168b0 RBP: 00007ffdb911689c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdb91168b0 R13: 00007f9d37811c05 R14: 00000000000a82cd R15: 00007ffdb91168f0 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8e5c10a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c10a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c10a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by syz-executor/5870: #0: ffff88802a6140e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88802a6140e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88802a6140e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super fs/super.c:506 [inline] #0: ffff88802a6140e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503 #1: ffffffff8e9d96c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 2 locks held by dhcpcd/15800: #0: ffff88805967a008 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff88805967a008 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:648 #1: ffffffff8e5cc638 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311 4 locks held by kworker/u8:35/15805: 2 locks held by syz.0.1919/16513: #0: ffffffff9042a010 ( cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e9d96c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629 2 locks held by syz-executor/16777: #0: ffff888030edc0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff888030edc0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff888030edc0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super fs/super.c:506 [inline] #0: ffff888030edc0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503 #1: ffffffff8e9d96c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 2 locks held by getty/16945: #0: ffff888034f270a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000349b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz.1.2079/17468: #0: ffffffff9042a010 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e9d96c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919 2 locks held by syz.1.2079/17470: #0: ffffffff9042a010 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e9d96c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919 2 locks held by syz-executor/17619: #0: ffff8880698fe0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880698fe0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880698fe0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super fs/super.c:506 [inline] #0: ffff8880698fe0e0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503 #1: ffffffff8e9d96c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 4 locks held by syz.6.2171/18688: #0: ffffffff90370850 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:566 #1: ffffffff90386b48 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x64/0x3c0 net/caif/caif_dev.c:528 #2: ffff88803353eb80 (&caifn->caifdevs.lock){+.+.}-{4:4}, at: caif_exit_net+0x7b/0x3c0 net/caif/caif_dev.c:529 #3: ffffffff8e5cc638 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343 2 locks held by syz.7.2215/18721: #0: ffffffff90370850 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:566 #1: ffffffff8e5cc500 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3815 2 locks held by syz.8.2219/18740: #0: ffffffff90370850 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:566 #1: ffffffff90386b48 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x21d/0x7d0 net/ipv4/ip_tunnel.c:1160 2 locks held by syz.8.2219/18742: #0: ffffffff90370850 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:566 #1: ffffffff90386b48 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x21d/0x7d0 net/ipv4/ip_tunnel.c:1160 1 lock held by dhcpcd-run-hook/18759: #0: ffff8880b843a458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:644 [inline] #0: ffff8880b843a458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:629 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 16053 Comm: kworker/u8:39 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5599 [inline] RIP: 0010:lock_is_held_type+0x99/0x150 kernel/locking/lockdep.c:5940 Code: 65 ff 05 82 71 45 08 41 8b 84 24 e8 0a 00 00 85 c0 7f 17 e9 92 00 00 00 41 83 c7 01 45 3b bc 24 e8 0a 00 00 0f 8d 80 00 00 00 <49> 63 c7 48 89 ee 48 8d 04 80 49 8d 5c c5 00 48 89 df e8 80 fe ff RSP: 0018:ffffc90003bb6d10 EFLAGS: 00000093 RAX: 0000000000000000 RBX: ffff88801ea88b40 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffff8880b853eb20 RDI: ffff88801ea88b40 RBP: ffff8880b853eb20 R08: 20e04e8f2740b4db R09: 0000000000000001 R10: 0000000000000004 R11: 0000000000000000 R12: ffff88801ea88000 R13: ffff88801ea88af0 R14: 00000000ffffffff R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8881247c3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd9e606e440 CR3: 000000000e380000 CR4: 00000000003526f0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] get_freelist+0x1a8/0x1e0 mm/slub.c:3656 ___slab_alloc+0x2b5/0x1740 mm/slub.c:3839 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] ieee802_11_parse_elems_full+0x1db/0x3780 net/mac80211/parse.c:1011 ieee802_11_parse_elems_crc net/mac80211/ieee80211_i.h:2462 [inline] ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2469 [inline] ieee80211_inform_bss+0x10b/0x1140 net/mac80211/scan.c:79 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline] cfg80211_inform_single_bss_data+0x8ea/0x1df0 net/wireless/scan.c:2379 cfg80211_inform_bss_data+0x224/0x3bd0 net/wireless/scan.c:3234 cfg80211_inform_bss_frame_data+0x26f/0x750 net/wireless/scan.c:3325 ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:226 ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1573 [inline] ieee80211_ibss_rx_queued_mgmt+0x1905/0x2fd0 net/mac80211/ibss.c:1600 ieee80211_iface_process_skb net/mac80211/iface.c:1699 [inline] ieee80211_iface_work+0xe2e/0x1360 net/mac80211/iface.c:1753 cfg80211_wiphy_work+0x2c7/0x580 net/wireless/core.c:435 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 vkms_vblank_simulate: vblank timer overrun