INFO: task syz.3.5834:20382 blocked for more than 143 seconds. Not tainted 6.6.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.5834 state:D stack:23208 pid:20382 ppid:17322 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14e2/0x4580 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 perf_pending_task_sync kernel/events/core.c:5242 [inline] _free_event+0x174/0xf30 kernel/events/core.c:5248 put_event kernel/events/core.c:5376 [inline] perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501 perf_release+0x3b/0x40 kernel/events/core.c:5511 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 get_signal+0x1235/0x1400 kernel/signal.c:2678 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9bb018e929 RSP: 002b:00007f9bb0f5dfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f9bb03b6080 RCX: 00007f9bb018e929 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000 RBP: 00007f9bb0210b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9bb03b6080 R15: 00007ffefca79cb8 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5555: #0: ffff8880324a20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900015972f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 1 lock held by kworker/0:4/5789: #0: ffff8880b8e3c458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 3 locks held by syz.0.6948/23447: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.96-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 23028 Comm: syz-executor Not tainted 6.6.96-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lockdep_hardirqs_on+0xaa/0x150 kernel/locking/lockdep.c:4423 Code: 48 3b 83 d0 0a 00 00 75 76 49 89 fe 48 c7 c7 c0 b2 aa 8a e8 78 15 00 00 65 c7 05 f5 1d 94 75 01 00 00 00 4c 89 b3 80 0a 00 00 <8b> 83 78 0a 00 00 ff c0 89 83 78 0a 00 00 89 83 90 0a 00 00 65 48 RSP: 0018:ffffc900035876d8 EFLAGS: 00000082 RAX: 0000000000000000 RBX: ffff888023959e00 RCX: 63db9f1a5546b700 RDX: dffffc0000000000 RSI: ffffffff8aaab2c0 RDI: ffffffff8afc6d00 RBP: ffffc90003587780 R08: ffffffff90da55af R09: 1ffffffff21b4ab5 R10: dffffc0000000000 R11: fffffbfff21b4ab6 R12: dffffc0000000000 R13: ffff888020e782a8 R14: ffffffff8a781146 R15: 1ffff920006b0ee0 FS: 000055557b475500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc4bb781ab8 CR3: 000000002ebe4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x86/0x110 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline] debug_check_no_obj_freed+0x51f/0x540 lib/debugobjects.c:1020 slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0xd2/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 vfree+0x299/0x320 mm/vmalloc.c:2865 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:882 [inline] get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline] do_ip6t_get_ctl+0xead/0x1150 net/ipv6/netfilter/ip6_tables.c:1677 nf_getsockopt+0x262/0x280 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x216/0x2c0 net/ipv6/ipv6_sockglue.c:1499 do_sock_getsockopt+0x38d/0x660 net/socket.c:2384 __sys_getsockopt net/socket.c:2413 [inline] __do_sys_getsockopt net/socket.c:2423 [inline] __se_sys_getsockopt net/socket.c:2420 [inline] __x64_sys_getsockopt+0x1d6/0x280 net/socket.c:2420 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc4bb59066a Code: ff c3 66 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b8 0f 1f 44 00 00 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7 RSP: 002b:00007ffe6ea0d658 EFLAGS: 00000212 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007ffe6ea0d6e0 RCX: 00007fc4bb59066a RDX: 0000000000000041 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffe6ea0d67c R09: 0079746972756365 R10: 00007ffe6ea0d6e0 R11: 0000000000000212 R12: 00007fc4bb782780 R13: 00007ffe6ea0d67c R14: 0000000000000000 R15: 00007fc4bb782e40