INFO: task syz-executor.5:7262 blocked for more than 143 seconds. Not tainted 5.7.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28904 7262 374 0x80004006 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x892/0x1d80 kernel/sched/core.c:4083 locks_remove_posix+0x277/0x4e0 fs/locks.c:2706 __sched_text_start+0x8/0x8 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] prepare_to_wait_event+0x129/0x650 kernel/sched/wait.c:305 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irqrestore+0x39/0x40 kernel/locking/spinlock.c:191 schedule+0xcd/0x2b0 kernel/sched/core.c:4158 wdm_flush+0x2ea/0x3c0 drivers/usb/class/cdc-wdm.c:590 wdm_poll+0x280/0x280 include/linux/poll.h:50 finish_wait+0x260/0x260 include/linux/list.h:301 task_work_add+0x97/0x120 kernel/task_work.c:35 wdm_poll+0x280/0x280 include/linux/poll.h:50 filp_close+0xb4/0x170 fs/open.c:1251 close_files fs/file.c:388 [inline] put_files_struct fs/file.c:416 [inline] put_files_struct+0x1d8/0x2e0 fs/file.c:413 exit_files+0x7e/0xa0 fs/file.c:445 do_exit+0xb36/0x2c80 kernel/exit.c:791 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4458 mm_update_next_owner+0x7a0/0x7a0 kernel/exit.c:375 lock_downgrade+0x720/0x720 kernel/locking/lockdep.c:4599 do_group_exit+0x125/0x340 kernel/exit.c:894 get_signal+0x480/0x2480 kernel/signal.c:2739 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4458 __might_fault mm/memory.c:4814 [inline] __might_fault+0x11f/0x1d0 mm/memory.c:4799 do_signal+0x88/0x1ae0 arch/x86/kernel/signal.c:784 __might_fault mm/memory.c:4814 [inline] __might_fault+0x190/0x1d0 mm/memory.c:4799 force_valid_ss arch/x86/kernel/signal.c:73 [inline] restore_sigcontext+0x620/0x620 arch/x86/kernel/signal.c:134 _copy_to_user+0x126/0x160 lib/usercopy.c:31 __do_sys_futex kernel/futex.c:3869 [inline] __se_sys_futex kernel/futex.c:3837 [inline] __x64_sys_futex+0x380/0x4f0 kernel/futex.c:3837 do_futex+0x1ae0/0x1ae0 include/linux/list.h:70 __do_sys_clock_gettime kernel/time/posix-timers.c:1094 [inline] __se_sys_clock_gettime kernel/time/posix-timers.c:1082 [inline] __x64_sys_clock_gettime+0x165/0x240 kernel/time/posix-timers.c:1082 exit_to_usermode_loop+0x1a2/0x200 arch/x86/entry/common.c:161 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x4e0/0x5a0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.4:7278 blocked for more than 143 seconds. Not tainted 5.7.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28552 7278 378 0x00000004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x892/0x1d80 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] prepare_to_wait_event+0x129/0x650 kernel/sched/wait.c:305 schedule+0xcd/0x2b0 kernel/sched/core.c:4158 wdm_flush+0x2ea/0x3c0 drivers/usb/class/cdc-wdm.c:590 wdm_poll+0x280/0x280 include/linux/poll.h:50 finish_wait+0x260/0x260 include/linux/list.h:301 wdm_poll+0x280/0x280 include/linux/poll.h:50 filp_close+0xb4/0x170 fs/open.c:1251 __close_fd+0x133/0x200 fs/file.c:641 __do_sys_close fs/open.c:1270 [inline] __se_sys_close fs/open.c:1268 [inline] __x64_sys_close+0x69/0x100 fs/open.c:1268 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x3c7/0x5d0 kernel/locking/lockdep.c:3702 do_syscall_64+0xb6/0x5a0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: ffffffff87111260 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5754 1 lock held by in:imklog/278: #0: ffff8881c656eff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by agetty/265: #0: ffff8881d197f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000a022e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x220/0x1b30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xef/0x16e lib/dump_stack.c:118 irq_force_complete_move.cold+0x13/0x47 arch/x86/kernel/apic/vector.c:1023 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 lapic_can_unplug_cpu.cold+0x3b/0x3b nmi_trigger_cpumask_backtrace+0x1db/0x207 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa99/0xfd0 kernel/hung_task.c:289 reset_hung_task_detector+0x30/0x30 kernel/hung_task.c:243 kthread+0x326/0x430 kernel/kthread.c:268 kthread_create_on_node+0xf0/0xf0 kernel/kthread.c:405 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 145 Comm: systemd-journal Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:cmpxchg_double_slab mm/slub.c:407 [inline] RIP: 0010:__slab_free+0xf5/0x4a0 mm/slub.c:2924 Code: 89 7c 24 20 e8 0c 35 2d 04 44 0f b6 54 24 10 48 89 04 24 8b 74 24 18 41 8b 45 08 48 8b 7c 24 20 a9 00 00 00 40 48 8b 4c 24 78 <74> 40 48 83 7c 24 30 00 0f 85 a9 01 00 00 48 89 da 4c 8b 5c 24 28 RSP: 0018:ffff8881d1fafc90 EFLAGS: 00000206 RAX: 0000000048042000 RBX: 00000000000c0009 RCX: 00000000000c0008 RDX: 0000000000000000 RSI: 00000000000c0008 RDI: 0000000000000000 RBP: ffff8881d1fafd50 R08: 0000000000000001 R09: ffffffff8169b1a9 R10: ffffea0007265a00 R11: ffffea00075dfc20 R12: ffffea0007265a00 R13: ffff8881da175400 R14: ffff8881c9968280 R15: 0000000000000000 FS: 00007f51608948c0(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f515e0b0018 CR3: 00000001d1fce000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:977 [inline] debug_check_no_obj_freed+0x213/0x449 lib/debugobjects.c:998 __phys_addr+0xc1/0x150 arch/x86/mm/physaddr.c:31 qlink_free mm/kasan/quarantine.c:148 [inline] qlist_free_all+0x32/0xa0 mm/kasan/quarantine.c:167 getname_flags fs/namei.c:138 [inline] getname_flags+0xd2/0x5b0 fs/namei.c:128 quarantine_reduce+0x135/0x170 mm/kasan/quarantine.c:260 __kasan_kmalloc.constprop.0+0x97/0xd0 mm/kasan/common.c:476 getname_flags fs/namei.c:138 [inline] getname_flags+0xd2/0x5b0 fs/namei.c:128 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc_node mm/slub.c:2797 [inline] slab_alloc mm/slub.c:2805 [inline] kmem_cache_alloc+0xd8/0x300 mm/slub.c:2810 getname_flags fs/namei.c:138 [inline] getname_flags+0xd2/0x5b0 fs/namei.c:128 getname fs/namei.c:209 [inline] user_path_create fs/namei.c:3502 [inline] do_mkdirat+0x8d/0x250 fs/namei.c:3640 __ia32_sys_mknod+0xb0/0xb0 fs/namei.c:3601 trace_hardirqs_off_caller+0x55/0x200 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xb6/0x5a0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x7f515fb50687 Code: 00 b8 ff ff ff ff c3 0f 1f 40 00 48 8b 05 09 d8 2b 00 64 c7 00 5f 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 d7 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc58656f78 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffc58659fe0 RCX: 00007f515fb50687 RDX: 0000000000000000 RSI: 00000000000001ed RDI: 000055b77d6d28a0 RBP: 00007ffc58656fb0 R08: 000055b77c4863e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 000055b77d6d28a0 R15: 00007ffc586575f0