block nbd1: shutting down sockets INFO: task syz-executor.0:23563 blocked for more than 140 seconds. Not tainted 4.14.262-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28136 23563 8005 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 flush_workqueue+0x3ce/0x1310 kernel/workqueue.c:2677 nbd_start_device_ioctl drivers/block/nbd.c:1263 [inline] __nbd_ioctl drivers/block/nbd.c:1334 [inline] nbd_ioctl+0x49d/0xa80 drivers/block/nbd.c:1374 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fe0a9ac6fe9 RSP: 002b:00007fe0a843c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fe0a9bd9f60 RCX: 00007fe0a9ac6fe9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fe0a9b2108d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcde4471cf R14: 00007fe0a843c300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by in:imklog/7777: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 fs/file.c:778 2 locks held by agetty/7930: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156 2 locks held by kworker/u5:8/8042: #0: ("knbd%d-recv"nbd->index){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: ((&args->work)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.262-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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4625 Comm: systemd-journal Not tainted 4.14.262-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880a123c180 task.stack: ffff8880a1240000 RIP: 0010:unwind_next_frame+0xf75/0x17d0 arch/x86/kernel/unwind_orc.c:474 RSP: 0018:ffff8880a1247868 EFLAGS: 00000803 RAX: 1ffffffff14e6897 RBX: 1ffff11014248f14 RCX: ffffffff8a7344ba RDX: ffff8880a1247968 RSI: dffffc0000000000 RDI: ffffffff8a7344bc RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000007 R10: ffff8880a1247c38 R11: 0000000000000001 R12: ffff8880a124795d R13: ffff8880a1247960 R14: ffff8880a1247978 R15: ffff8880a1247928 FS: 00007fe503e5a8c0(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe501350000 CR3: 00000000a12bd000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __save_stack_trace+0x90/0x160 arch/x86/kernel/stacktrace.c:44 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kmem_cache_free+0x7c/0x2b0 mm/slab.c:3758 putname+0xcd/0x110 fs/namei.c:259 filename_parentat+0x477/0x520 fs/namei.c:2430 filename_create+0x8a/0x3f0 fs/namei.c:3657 user_path_create fs/namei.c:3732 [inline] SYSC_mkdirat fs/namei.c:3864 [inline] SyS_mkdirat+0x95/0x270 fs/namei.c:3856 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fe503115687 RSP: 002b:00007ffd8fc99e38 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffd8fc9cd50 RCX: 00007fe503115687 RDX: 00007fe503b86a00 RSI: 00000000000001ed RDI: 00005598b94ad8a0 RBP: 00007ffd8fc99e70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffd8fc9cd50 R15: 00007ffd8fc9a360 Code: fe ff ff e9 a8 f4 ff ff 4c 8b 54 24 58 48 8d 79 02 48 be 00 00 00 00 00 fc ff df 49 8d 57 40 48 89 f8 48 c1 e8 03 44 0f b6 04 30 <48> 8d 41 03 49 89 c1 49 c1 e9 03 41 0f b6 34 31 49 89 f9 41 83 ---------------- Code disassembly (best guess), 3 bytes skipped: 0: e9 a8 f4 ff ff jmpq 0xfffff4ad 5: 4c 8b 54 24 58 mov 0x58(%rsp),%r10 a: 48 8d 79 02 lea 0x2(%rcx),%rdi e: 48 be 00 00 00 00 00 movabs $0xdffffc0000000000,%rsi 15: fc ff df 18: 49 8d 57 40 lea 0x40(%r15),%rdx 1c: 48 89 f8 mov %rdi,%rax 1f: 48 c1 e8 03 shr $0x3,%rax 23: 44 0f b6 04 30 movzbl (%rax,%rsi,1),%r8d * 28: 48 8d 41 03 lea 0x3(%rcx),%rax <-- trapping instruction 2c: 49 89 c1 mov %rax,%r9 2f: 49 c1 e9 03 shr $0x3,%r9 33: 41 0f b6 34 31 movzbl (%r9,%rsi,1),%esi 38: 49 89 f9 mov %rdi,%r9 3b: 41 rex.B 3c: 83 .byte 0x83