attempt to access beyond end of device loop1: rw=4096, want=136, limit=1 gfs2: error 10 reading superblock INFO: task syz-executor0:25405 blocked for more than 120 seconds. Not tainted 4.17.0-rc7+ #76 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D23672 25405 14235 0x00000004 Call Trace: context_switch kernel/sched/core.c:2859 [inline] __schedule+0x801/0x1e30 kernel/sched/core.c:3501 schedule+0xef/0x430 kernel/sched/core.c:3545 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3603 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0xe38/0x17f0 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __fdget_pos+0x1a9/0x1e0 fs/file.c:766 fdget_pos include/linux/file.h:67 [inline] ksys_write+0x77/0x250 fs/read_write.c:593 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007fd728448c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd7284496d4 RCX: 0000000000455a09 RDX: 00000000ffffff43 RSI: 0000000020000180 RDI: 0000000000000013 RBP: 000000000072bf50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000007b1 R14: 0000000000700938 R15: 0000000000000001 Showing all locks held in the system: 2 locks held by khungtaskd/893: #0: 0000000006eeebb3 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: 0000000006eeebb3 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249 #1: 00000000854e54c0 (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470 2 locks held by getty/4509: #0: 00000000f09b2698 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000022ed4d1f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4510: #0: 00000000ed54cf02 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000064342697 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4511: #0: 00000000e3a3dc9e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000669e0930 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4512: #0: 0000000025a624ae (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000051b0aeea (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4513: #0: 00000000f386e2e7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000003f0e2088 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4514: #0: 00000000f145837f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ba61bd69 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4515: #0: 00000000f20bd780 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000003d2ebe86 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 1 lock held by syz-executor0/25405: #0: 0000000013a83462 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 893 Comm: khungtaskd Not tainted 4.17.0-rc7+ #76 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+0x1b9/0x294 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 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:138 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0xc10/0xf60 kernel/hung_task.c:249 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2106 Comm: kworker/1:2 Not tainted 4.17.0-rc7+ #76 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events rht_deferred_worker RIP: 0010:INIT_HLIST_NODE include/linux/list.h:631 [inline] RIP: 0010:hlist_del_init include/linux/list.h:665 [inline] RIP: 0010:hash_del include/linux/hashtable.h:107 [inline] RIP: 0010:process_one_work+0xe8a/0x1b50 kernel/workqueue.c:2180 RSP: 0018:ffff8801cdc07760 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff8801daf2c020 RCX: ffffffff814e17a7 RDX: 1ffff10039b863e1 RSI: ffffffff814e1879 RDI: 0000000000000005 RBP: ffff8801cdc07b60 R08: ffff8801cdc68780 R09: ffffed003b5e57c0 R10: ffffed003b5e57c0 R11: ffff8801daf2be03 R12: 0000000000000000 R13: 1ffff10039b80f27 R14: dffffc0000000000 R15: ffff8801cdc31f00 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001c8021000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Code: 85 76 09 00 00 48 8b 95 40 fc ff ff 49 c7 07 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 5d 09 00 00 <49> c7 47 08 00 00 00 00 e8 99 29 2b 00 48 8b 95 28 fc ff ff 48