audit: type=1400 audit(1581798586.477:36): avc: denied { map } for pid=7940 comm="syz-executor800" path="/root/syz-executor800336106" dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 IPVS: ftp: loaded support on port[0] = 21 block nbd0: shutting down sockets INFO: task syz-executor800:7942 blocked for more than 140 seconds. Not tainted 4.19.104-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor800 D27936 7942 7941 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1782 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 flush_workqueue+0x40f/0x14b0 kernel/workqueue.c:2713 nbd_start_device_ioctl drivers/block/nbd.c:1252 [inline] __nbd_ioctl drivers/block/nbd.c:1323 [inline] nbd_ioctl+0x546/0xcc0 drivers/block/nbd.c:1363 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0xc2c/0x1ab3 block/ioctl.c:601 block_ioctl+0xee/0x130 fs/block_dev.c:1894 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4454a9 Code: Bad RIP value. RSP: 002b:00007fff8c5db528 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004454a9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 0000000000000004 R08: 0000000000000004 R09: 0000000000000000 R10: 00007fff8c5db080 R11: 0000000000000246 R12: 00000000011bc914 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1081: #0: 00000000c63fdad1 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 2 locks held by kworker/u5:0/1217: #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000003a8b1387 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124 #1: 0000000032fea809 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 1 lock held by rsyslogd/7791: 2 locks held by getty/7913: #0: 000000005274481b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000002f7f9ffb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7914: #0: 000000002ce50d72 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000092af2ede (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7915: #0: 0000000055bd61bc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a373e729 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7916: #0: 00000000cc6be82e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000007c6abcb3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7917: #0: 00000000b1af6aef (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000e681d9f9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7918: #0: 00000000fe3aed4b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003fcd29a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7919: #0: 000000008ef0a1f4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000030beef78 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1081 Comm: khungtaskd Not tainted 4.19.104-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+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60