audit: type=1400 audit(1580473021.533:7180): avc: denied { map } for pid=1526 comm="sh" path="/bin/dash" dev="sda1" ino=1473 scontext=system_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 INFO: task login:7267 blocked for more than 140 seconds. Not tainted 4.14.169-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. login D25920 7267 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_timeout+0x93b/0xe10 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2891 tty_buffer_flush_work+0x16/0x20 drivers/tty/tty_buffer.c:612 n_tty_read+0x813/0x17d0 drivers/tty/n_tty.c:2199 tty_read+0x171/0x270 drivers/tty/tty_io.c:866 __vfs_read+0x105/0x6a0 fs/read_write.c:411 vfs_read+0x137/0x350 fs/read_write.c:447 SYSC_read fs/read_write.c:574 [inline] SyS_read+0xfd/0x230 fs/read_write.c:567 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7f53290aa310 RSP: 002b:00007ffc513afed8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f53290aa310 RDX: 00000000000001ff RSI: 00007ffc513b0140 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00007f532998d700 R09: 0000000000000000 R10: 00007ffc513afe90 R11: 0000000000000246 R12: 00007ffc513b0140 R13: 0000000000000000 R14: 0000000000000001 R15: 000000000060b798 INFO: task kworker/u4:5:7458 blocked for more than 140 seconds. Not tainted 4.14.169-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:5 D26528 7458 2 0x80000000 Workqueue: events_unbound flush_to_ldisc Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 flush_to_ldisc+0x39/0x400 drivers/tty/tty_buffer.c:499 process_one_work+0x863/0x1600 kernel/workqueue.c:2114 process_scheduled_works kernel/workqueue.c:2174 [inline] worker_thread+0x787/0x1050 kernel/workqueue.c:2253 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Showing all locks held in the system: 1 lock held by khungtaskd/1050: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 2 locks held by login/7267: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7268: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7269: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7270: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7271: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7272: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 3 locks held by kworker/u4:5/7458: #0: ("events_unbound"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events_unbound"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events_unbound"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events_unbound"){+.+.}, at: [] process_one_work+0x76e/0x1600 kernel/workqueue.c:2085 #1: ((&buf->work)){+.+.}, at: [] process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089 #2: (&buf->lock){+.+.}, at: [] flush_to_ldisc+0x39/0x400 drivers/tty/tty_buffer.c:499 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1050 Comm: khungtaskd Not tainted 4.14.169-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1444 Comm: syz-executor.4 Not tainted 4.14.169-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880a5838240 task.stack: ffff88805da68000 RIP: 0010:match_held_lock+0x2d5/0x5f0 kernel/locking/lockdep.c:3586 RSP: 0018:ffff88805da6f650 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff8880a5838ae8 RCX: ffff8880a5838ac0 RDX: 0000000000000000 RSI: ffffffff87fa3f60 RDI: ffff8880a5838b0a RBP: ffff88805da6f6c8 R08: 0000000000000000 R09: ffff8880a5838b58 R10: ffff8880a5838b38 R11: ffff8880a5838240 R12: 0000000000000000 R13: 1ffff1100bb4decc R14: ffffffff87fa3f60 R15: ffff88805da6f6a0 FS: 00007f49c79cc700(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa60af2098e CR3: 000000004e474000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held+0xb6/0x140 kernel/locking/lockdep.c:3814 lock_is_held_type+0x110/0x210 kernel/locking/lockdep.c:4032 lock_is_held include/linux/lockdep.h:437 [inline] task_css include/linux/cgroup.h:481 [inline] task_ca kernel/sched/cpuacct.c:54 [inline] cpuacct_charge+0x273/0x360 kernel/sched/cpuacct.c:360 update_curr+0x2d9/0x6a0 kernel/sched/fair.c:856 pick_next_task_fair+0x661/0x1430 kernel/sched/fair.c:6303 pick_next_task kernel/sched/core.c:3232 [inline] __schedule+0x43e/0x1cd0 kernel/sched/core.c:3357 schedule+0x92/0x1c0 kernel/sched/core.c:3428 paste_selection+0x293/0x3f2 drivers/tty/vt/selection.c:355 tioclinux+0x10e/0x400 drivers/tty/vt/vt.c:2696 vt_ioctl+0x180c/0x2170 drivers/tty/vt/vt_ioctl.c:364 tty_ioctl+0x841/0x1320 drivers/tty/tty_io.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b349 RSP: 002b:00007f49c79cbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f49c79cc6d4 RCX: 000000000045b349 RDX: 0000000020000140 RSI: 000000000000541c RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000056c R14: 00000000004c6aed R15: 000000000075bf2c Code: 85 00 03 00 00 44 8b 25 ea b0 6d 08 45 85 e4 0f 84 7e ec 00 00 45 31 e4 48 b8 00 00 00 00 00 fc ff df 49 c7 44 05 00 00 00 00 00 <48> 83 c4 50 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 41 bc 01