INFO: task syz.0.3692:15919 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.0.3692 state:D stack:25464 pid:15919 tgid:15913 ppid:12368 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5354 [inline] __schedule+0x165c/0x5520 kernel/sched/core.c:6966 __schedule_loop kernel/sched/core.c:7049 [inline] schedule+0x164/0x360 kernel/sched/core.c:7064 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7121 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 user_get_super+0xc8/0x120 fs/super.c:1001 quotactl_block fs/quota/quota.c:889 [inline] __do_sys_quotactl fs/quota/quota.c:955 [inline] __se_sys_quotactl+0x540/0x9e0 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f289ff9c819 RSP: 002b:00007f28a0e65028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007f28a0215fa0 RCX: 00007f289ff9c819 RDX: 0000000000000000 RSI: 0000200000000200 RDI: ffffffff80000801 RBP: 00007f28a0032c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000040 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f28a0216038 R14: 00007f28a0215fa0 R15: 00007ffc437183d8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e95d060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e95d060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e95d060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5594: #0: ffff8880379c00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5835: 2 locks held by dhcpcd/12252: #0: ffff888078708e40 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #0: ffff888078708e40 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:720 [inline] #0: ffff888078708e40 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1513 #1: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 3 locks held by kworker/1:5/14613: #0: ffff88813fe4f140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline] #0: ffff88813fe4f140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361 #1: ffffc90005587c40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline] #1: ffffc90005587c40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361 #2: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #2: ffffffff8e963368 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.0.3692/15919: #0: ffff88805635e0d8 (&type->s_umount_key#56){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805635e0d8 (&type->s_umount_key#56){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz-executor/18637: 1 lock held by syz.1.5070/19428: #0: ffff88805635e0d8 (&type->s_umount_key#56){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88805635e0d8 (&type->s_umount_key#56){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.9.5282/20123: 3 locks held by syz.3.5284/20125: 3 locks held by dhcpcd-run-hook/20157: #0: ffff8880b863ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff888034ebb2f8 (&sig->wait_chldexit){....}-{3:3}, at: __wake_up_common_lock+0x2f/0x1f0 kernel/sched/wait.c:124 ============================================= NMI backtrace for cpu 0 CPU: 0 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 03/18/2026 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:162 [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:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 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: 20151 Comm: syz.7.5288 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:kfree_const+0x4/0x40 mm/util.c:44 Code: 5d e9 c0 7f a4 09 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <53> 48 89 fb e8 23 5a b8 ff 48 81 fb 00 00 c0 8b 0f 92 c0 48 81 fb RSP: 0018:ffffc90005ec78d8 EFLAGS: 00000293 RAX: ffffffff8ba5d785 RBX: ffff888035344c00 RCX: ffff88804d1a0000 RDX: 0000000000000000 RSI: ffffffff8dfc116d RDI: ffff888035344c00 RBP: 0000000000000000 R08: ffffffff9031a6f7 R09: 1ffffffff20634de R10: dffffc0000000000 R11: fffffbfff20634df R12: 1ffffffff18a5f84 R13: 0000000000000000 R14: 1ffff1100af5d222 R15: ffffffff8c52fc20 FS: 0000000000000000(0000) GS:ffff88812535c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f70ca73d1d4 CR3: 00000000767ea000 CR4: 00000000003526f0 Call Trace: kobject_cleanup lib/kobject.c:695 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x26d/0x560 lib/kobject.c:737 hci_unregister_dev+0x38b/0x5a0 net/bluetooth/hci_core.c:2734 vhci_release+0x152/0x1a0 drivers/bluetooth/hci_vhci.c:690 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x70f/0x22c0 kernel/exit.c:974 do_group_exit+0x21b/0x2d0 kernel/exit.c:1116 get_signal+0x1284/0x1330 kernel/signal.c:3036 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe74859c819 Code: Unable to access opcode bytes at 0x7fe74859c7ef. RSP: 002b:00007fe749499028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: fffffffffffffff5 RBX: 00007fe748815fa0 RCX: 00007fe74859c819 RDX: 0000000000000094 RSI: 0000200000000840 RDI: 0000000000000005 RBP: 00007fe748632c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe748816038 R14: 00007fe748815fa0 R15: 00007fff0f2ffe38