syzbot


INFO: task hung in io_uring_del_task_file

Status: auto-closed as invalid on 2021/08/14 01:18
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+c70bf1f371cd5a6bb898@syzkaller.appspotmail.com
First crash: 1075d, last: 1075d

Sample crash report:
INFO: task syz-executor.1:3295 blocked for more than 143 seconds.
      Not tainted 5.13.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:28824 pid: 3295 ppid:  8521 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0x916/0x23e0 kernel/sched/core.c:5147
 schedule+0xcf/0x270 kernel/sched/core.c:5226
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:5285
 __mutex_lock_common kernel/locking/mutex.c:1026 [inline]
 __mutex_lock+0x81f/0x1120 kernel/locking/mutex.c:1096
 io_uring_del_task_file+0x107/0x360 fs/io_uring.c:9027
 io_uring_clean_tctx fs/io_uring.c:9042 [inline]
 __io_uring_cancel+0x3ca/0x530 fs/io_uring.c:9136
 io_uring_files_cancel include/linux/io_uring.h:16 [inline]
 do_exit+0x299/0x2a60 kernel/exit.c:781
 do_group_exit+0x125/0x310 kernel/exit.c:923
 get_signal+0x47f/0x2150 kernel/signal.c:2818
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x171/0x280 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
RSP: 002b:00007f171a16a218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056c010 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056c010
RBP: 000000000056c008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c014
R13: 0000000000a9fb1f R14: 00007f171a16a300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1588:
 #0: ffffffff8bf792a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333
1 lock held by khugepaged/1651:
1 lock held by in:imklog/8126:
 #0: ffff88801746c0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974
1 lock held by syz-executor.1/3271:
1 lock held by syz-executor.1/3295:
 #0: ffff888017046128 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_del_task_file+0x107/0x360 fs/io_uring.c:9027
1 lock held by syz-executor.1/3296:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1588 Comm: khungtaskd Not tainted 5.13.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd48/0xfb0 kernel/hung_task.c:294
 kthread+0x3b1/0x4a0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3271 Comm: syz-executor.1 Not tainted 5.13.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unwind_next_frame+0x838/0x1ce0 arch/x86/kernel/unwind_orc.c:466
Code: c0 40 84 c7 0f 85 bc 0f 00 00 49 0f bf 30 48 01 d6 48 89 74 24 60 e9 d8 fd ff ff 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 <48> c1 ea 03 80 3c 02 00 0f 85 cb 12 00 00 4c 89 c0 49 8b 56 38 48
RSP: 0018:ffffc90017c7f528 EFLAGS: 00000297
RAX: dffffc0000000000 RBX: 1ffff92002f8fead RCX: ffffffff8e511b17
RDX: ffffc90017c7f638 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff8e511b12 R09: ffffffff8e511b12
R10: fffff52002f8fecb R11: 0000000000084087 R12: ffffc90017c7f648
R13: ffffc90017c7f635 R14: ffffc90017c7f600 R15: ffffffff8e511b16
FS:  00007f171a18b700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd625a631e8 CR3: 00000000222f2000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:428 [inline]
 ____kasan_kmalloc mm/kasan/common.c:507 [inline]
 ____kasan_kmalloc mm/kasan/common.c:466 [inline]
 __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:516
 kmalloc include/linux/slab.h:556 [inline]
 io_add_buffers fs/io_uring.c:3986 [inline]
 io_provide_buffers fs/io_uring.c:4020 [inline]
 io_issue_sqe+0x2670/0x66b0 fs/io_uring.c:6192
 __io_queue_sqe+0x18e/0x10f0 fs/io_uring.c:6414
 io_queue_sqe+0x5a5/0xb80 fs/io_uring.c:6463
 io_submit_sqe fs/io_uring.c:6626 [inline]
 io_submit_sqes+0x5a0d/0x6bd0 fs/io_uring.c:6734
 __do_sys_io_uring_enter+0xeaf/0x1d50 fs/io_uring.c:9319
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: Unable to access opcode bytes at RIP 0x4665af.
RSP: 002b:00007f171a18b188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 000000000000450c RDI: 0000000000000003
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 0000000000a9fb1f R14: 00007f171a18b300 R15: 0000000000022000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/16 01:17 upstream f36edc5533b2 f54a5c09 .config console log report info ci-upstream-kasan-gce INFO: task hung in io_uring_del_task_file
* Struck through repros no longer work on HEAD.