INFO: task kworker/1:3:8429 blocked for more than 140 seconds. Not tainted 4.14.225-syzkaller #0 loop2p4: rw=0, want=264072, limit=8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. attempt to access beyond end of device loop2p4: rw=0, want=264072, limit=8 kworker/1:3 D26720 8429 2 0x80000000 Buffer I/O error on dev loop2p4, logical block 33008, async page read Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 usb_kill_urb.part.0+0x125/0x190 drivers/usb/core/urb.c:691 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:686 usb_start_wait_urb+0x209/0x440 drivers/usb/core/message.c:62 usb_internal_control_msg drivers/usb/core/message.c:100 [inline] usb_control_msg+0x302/0x450 drivers/usb/core/message.c:151 usb_get_descriptor+0xc0/0x160 drivers/usb/core/message.c:652 usb_get_device_descriptor+0x71/0xd0 drivers/usb/core/message.c:924 hub_port_init+0x629/0x2970 drivers/usb/core/hub.c:4647 hub_port_connect drivers/usb/core/hub.c:4905 [inline] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] port_event drivers/usb/core/hub.c:5194 [inline] hub_event+0x18fd/0x3d70 drivers/usb/core/hub.c:5274 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Showing all locks held in the system: 2 locks held by kworker/u4:0/5: #0: ("events_unbound"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&sub_info->work)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 1 lock held by khungtaskd/1530: #0: (tasklist_lock){.+.?}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 5 locks held by kworker/1:3/8429: #0: ("usb_hub_wq"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&hub->events)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&dev->mutex){....}, at: [] device_lock include/linux/device.h:1081 [inline] #2: (&dev->mutex){....}, at: [] hub_event+0x108/0x3d70 drivers/usb/core/hub.c:5220 #3: (&port_dev->status_lock){+.+.}, at: [] usb_lock_port drivers/usb/core/hub.c:2934 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect drivers/usb/core/hub.c:4904 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_port_connect_change drivers/usb/core/hub.c:5088 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] port_event drivers/usb/core/hub.c:5194 [inline] #3: (&port_dev->status_lock){+.+.}, at: [] hub_event+0x18e8/0x3d70 drivers/usb/core/hub.c:5274 #4: (hcd->address0_mutex){+.+.}, at: [] hub_port_init+0x15b/0x2970 drivers/usb/core/hub.c:4429 ============================================= attempt to access beyond end of device loop2p4: rw=0, want=264072, limit=8 attempt to access beyond end of device loop2p4: rw=0, want=264072, limit=8 Buffer I/O error on dev loop2p4, logical block 33008, async page read NMI backtrace for cpu 1 CPU: 1 PID: 1530 Comm: khungtaskd Not tainted 4.14.225-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+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 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: 4622 Comm: systemd-journal Not tainted 4.14.225-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880a17940c0 task.stack: ffff8880a1798000 RIP: 0010:qlink_to_object mm/kasan/quarantine.c:136 [inline] RIP: 0010:qlink_free mm/kasan/quarantine.c:141 [inline] RIP: 0010:qlist_free_all+0x32/0x140 mm/kasan/quarantine.c:166 RSP: 0018:ffff8880a179fb48 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b2d8e040 RCX: ffffea0002c6679f RDX: 0000000000000000 RSI: ffff8880a1794948 RDI: ffff8880b2d8e040 RBP: 0000000000000000 R08: ffffffff8b99c1d0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88804e60a438 R13: ffff8880a179fb80 R14: ffff88813fe801c0 R15: 0000000000000286 FS: 00007f08a5b5c8c0(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f903017da21 CR3: 00000000a2151000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: quarantine_reduce+0x185/0x200 mm/kasan/quarantine.c:259 kasan_kmalloc+0xa2/0x160 mm/kasan/kasan.c:536 slab_post_alloc_hook mm/slab.h:442 [inline] slab_alloc mm/slab.c:3390 [inline] kmem_cache_alloc+0x111/0x3c0 mm/slab.c:3550 prepare_creds+0x39/0x490 kernel/cred.c:255 SYSC_faccessat fs/open.c:365 [inline] SyS_faccessat+0x7b/0x680 fs/open.c:353 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f08a4e189c7 RSP: 002b:00007fffed640858 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007fffed643770 RCX: 00007f08a4e189c7 RDX: 00007f08a5889a00 RSI: 0000000000000000 RDI: 000055fe39da09a3 RBP: 00007fffed640890 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fffed643770 R15: 00007fffed640d80 Code: 54 55 53 48 8b 1f 48 85 db 0f 84 08 01 00 00 48 89 f5 49 89 fd 48 85 ed 49 89 ee 0f 84 8b 00 00 00 49 63 86 fc 00 00 00 4c 8b 23 <48> 29 c3 48 83 3d 83 e4 71 07 00 0f 84 e6 00 00 00 9c 58 0f 1f