audit: type=1800 audit(1581973009.295:1092): pid=30894 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="file0" dev="sda1" ino=17075 res=0 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.0:7296 blocked for more than 140 seconds. Not tainted 4.14.171-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D24432 7296 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 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x5ce/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:718 [inline] vfs_unlink+0xc6/0x480 fs/namei.c:4018 do_unlinkat+0x33d/0x600 fs/namei.c:4092 SYSC_unlink fs/namei.c:4139 [inline] SyS_unlink+0x1b/0x20 fs/namei.c:4137 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c417 RSP: 002b:00007ffd45e3b9f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045c417 RDX: 00007ffd45e3ba10 RSI: 00007ffd45e3ba10 RDI: 00007ffd45e3baa0 RBP: 0000000000000ab4 R08: 0000000000000000 R09: 0000000000000009 R10: 0000000000000003 R11: 0000000000000246 R12: 00007ffd45e3cb30 R13: 000000000103f940 R14: 0000000000000000 R15: 00007ffd45e3cb30 Showing all locks held in the system: 1 lock held by khungtaskd/1057: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 1 lock held by rsyslogd/7126: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/7249: #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/7250: #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/7251: #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/7252: #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/7253: #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/7254: #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/7255: #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 syz-executor.0/7296: #0: (sb_writers#4){.+.+}, at: [] sb_start_write include/linux/fs.h:1548 [inline] #0: (sb_writers#4){.+.+}, at: [] mnt_want_write+0x3f/0xb0 fs/namespace.c:386 #1: (&type->i_mutex_dir_key#3/1){+.+.}, at: [] inode_lock_nested include/linux/fs.h:753 [inline] #1: (&type->i_mutex_dir_key#3/1){+.+.}, at: [] do_unlinkat+0x22f/0x600 fs/namei.c:4078 #2: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_lock include/linux/fs.h:718 [inline] #2: (&sb->s_type->i_mutex_key#9){++++}, at: [] vfs_unlink+0xc6/0x480 fs/namei.c:4018 2 locks held by syz-executor.0/30822: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] aio_write+0x426/0x4f0 fs/aio.c:1552 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 4.14.171-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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7524 Comm: kworker/u4:6 Not tainted 4.14.171-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff88805661e140 task.stack: ffff888056620000 RIP: 0010:__preempt_count_dec_and_test arch/x86/include/asm/preempt.h:91 [inline] RIP: 0010:rcu_read_unlock_sched_notrace include/linux/rcupdate.h:775 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0x2e8/0x430 kernel/locking/lockdep.c:3993 RSP: 0018:ffff888056627c90 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8880a4ad6d28 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 1ffffffff0f817ad RDI: ffffffff87c0bd68 RBP: ffff888056627cd8 R08: 0000000000000002 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff87f84ee0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fab82242140 CR3: 000000007f7f3000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:629 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x107/0x6d0 net/batman-adv/network-coding.c:726 process_one_work+0x863/0x1600 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: ff d0 48 89 d8 5a 48 c1 e8 03 59 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 0f 85 c6 00 00 00 48 8b 03 48 85 c0 75 9c 44 8b 5d c0 <65> ff 0d 31 74 b9 7e 0f 85 2c fe ff ff e8 da c8 b7 ff e9 22 fe