syzbot


INFO: task hung in fuse_sb_destroy

Status: fixed on 2018/12/07 08:24
Subsystems: fuse
[Documentation on labels]
Reported-by: syzbot+6339eda9cb4ebbc4c37b@syzkaller.appspotmail.com
Fix commit: 7fabaf303458 fuse: fix leaked notify reply
First crash: 2055d, last: 2055d
Discussions (8)
Title Replies (including bot) Last reply
[PATCH 3.16 000/305] 3.16.63-rc1 review 313 (313) 2019/06/07 15:34
[PATCH 3.18 00/90] 3.18.126-stable review 102 (102) 2018/11/22 06:30
[PATCH 4.19 000/205] 4.19.3-stable review 214 (214) 2018/11/21 08:05
[PATCH 4.4 000/160] 4.4.164-stable review 169 (169) 2018/11/21 07:59
[PATCH 4.18 000/171] 4.18.20-stable review 176 (176) 2018/11/20 20:40
[PATCH 4.14 000/124] 4.14.82-stable review 131 (131) 2018/11/20 20:39
[PATCH 4.9 00/83] 4.9.138-stable review 89 (89) 2018/11/20 20:39
INFO: task hung in fuse_sb_destroy 5 (7) 2018/11/07 15:30

Sample crash report:
INFO: task syz-executor221:17414 blocked for more than 140 seconds.
      Not tainted 4.19.0+ #313
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor221 D23048 17414   5652 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 fuse_wait_aborted+0x20b/0x320 fs/fuse/dev.c:2155
 fuse_sb_destroy+0xe2/0x1d0 fs/fuse/inode.c:1224
 fuse_kill_sb_anon+0x15/0x20 fs/fuse/inode.c:1234
 deactivate_locked_super+0x97/0x100 fs/super.c:329
 deactivate_super+0x2bb/0x320 fs/super.c:360
 cleanup_mnt+0xbf/0x160 fs/namespace.c:1098
 __cleanup_mnt+0x16/0x20 fs/namespace.c:1105
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446689
Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f621e979da8 EFLAGS: 00000293 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00000000006dbc28 RCX: 0000000000446689
RDX: 0000000000446689 RSI: 000000000000000a RDI: 0000000020000180
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000006dbc2c
R13: 0030656c69662f2e R14: 65646f6d746f6f72 R15: 0000000000000000

Showing all locks held in the system:
1 lock held by khungtaskd/1009:
 #0: 0000000095618e4f (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379
5 locks held by rsyslogd/5530:
 #0: 0000000028bad575 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766
 #1: 00000000e31592cd (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1126 [inline]
 #1: 00000000e31592cd (&rq->lock){-.-.}, at: __schedule+0x236/0x21d0 kernel/sched/core.c:3410
 #2: 0000000095618e4f (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:418 [inline]
 #2: 0000000095618e4f (rcu_read_lock){....}, at: update_curr+0x383/0xbd0 kernel/sched/fair.c:830
 #3: 00000000e31592cd (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1126 [inline]
 #3: 00000000e31592cd (&rq->lock){-.-.}, at: ttwu_queue kernel/sched/core.c:1845 [inline]
 #3: 00000000e31592cd (&rq->lock){-.-.}, at: try_to_wake_up+0x9f6/0x1490 kernel/sched/core.c:2057
 #4: 0000000095618e4f (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:418 [inline]
 #4: 0000000095618e4f (rcu_read_lock){....}, at: update_curr+0x383/0xbd0 kernel/sched/fair.c:830
2 locks held by getty/5620:
 #0: 00000000492d5ad8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 0000000088c4d769 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/5621:
 #0: 00000000ed56cf3c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000a8112d49 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/5622:
 #0: 00000000858703c2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000b20ff0f8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/5623:
 #0: 00000000a0163126 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000cb4be99e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/5624:
 #0: 000000006eab39a0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000341e7ea5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/5625:
 #0: 00000000e1bb9e75 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000e6c38e03 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/5626:
 #0: 00000000437eab2d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000031acd5c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by kworker/1:0/5718:
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: __write_once_size include/linux/compiler.h:206 [inline]
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 0000000003693dce ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0xb43/0x1c40 kernel/workqueue.c:2124
 #1: 00000000fdcab2d3 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128
1 lock held by syz-executor221/17414:
 #0: 000000003df3056e (&type->s_umount_key#39){+.+.}, at: deactivate_super+0x2b3/0x320 fs/super.c:359
1 lock held by syz-executor221/18647:
 #0: 00000000dd0c9ec5 (rcu_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline]
 #0: 00000000dd0c9ec5 (rcu_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited.constprop.58+0x7c7/0x9d0 kernel/rcu/tree_exp.h:620
1 lock held by syz-executor221/18653:
 #0: 00000000dd0c9ec5 (rcu_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline]
 #0: 00000000dd0c9ec5 (rcu_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited.constprop.58+0x7af/0x9d0 kernel/rcu/tree_exp.h:620

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

NMI backtrace for cpu 0
CPU: 0 PID: 1009 Comm: khungtaskd Not tainted 4.19.0+ #313
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+0x244/0x39d lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1e8/0x22a 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:144 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xb51/0x1060 kernel/hung_task.c:289
 kthread+0x35a/0x440 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:350
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18647 Comm: syz-executor221 Not tainted 4.19.0+ #313
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:outb arch/x86/include/asm/io.h:334 [inline]
RIP: 0010:io_serial_out+0x73/0x90 drivers/tty/serial/8250/8250_port.c:455
Code: 00 49 8d 7c 24 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 19 41 03 5c 24 38 44 89 e8 89 da ee <5b> 41 5c 41 5d 5d c3 e8 e1 66 e0 fd eb c0 e8 3a 67 e0 fd eb e0 0f
RSP: 0018:ffff8801cc666f90 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: ffffffff83e257a6 RDI: ffffffff8bae5158
RBP: ffff8801cc666fa8 R08: ffff8801bf0b0600 R09: ffffed00398ccde3
R10: ffffed00398ccde3 R11: 0000000000000003 R12: ffffffff8bae5120
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8bae5168
FS:  00007f621e97a700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f313a840000 CR3: 00000001c3654000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 serial_port_out include/linux/serial_core.h:276 [inline]
 serial8250_console_write+0x34b/0xb10 drivers/tty/serial/8250/8250_port.c:3276
 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:586
 call_console_drivers kernel/printk/printk.c:1728 [inline]
 console_unlock+0xb1f/0x1190 kernel/printk/printk.c:2414
 vprintk_emit+0x391/0x990 kernel/printk/printk.c:1922
 vprintk_default+0x28/0x30 kernel/printk/printk.c:1964
 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398
 printk+0xa7/0xcf kernel/printk/printk.c:1997
 kobject_cleanup lib/kobject.c:638 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put.cold.9+0x83/0x2e4 lib/kobject.c:708
 put_device drivers/base/core.c:2024 [inline]
 device_unregister+0x28/0x30 drivers/base/core.c:2114
 bdi_unregister+0x5ed/0x880 mm/backing-dev.c:948
 release_bdi mm/backing-dev.c:964 [inline]
 kref_put include/linux/kref.h:70 [inline]
 bdi_put+0x153/0x180 mm/backing-dev.c:973
 generic_shutdown_super+0x3c8/0x530 fs/super.c:470
 kill_anon_super+0x3e/0x60 fs/super.c:1032
 fuse_kill_sb_anon+0x1d/0x20 fs/fuse/inode.c:1235
 deactivate_locked_super+0x97/0x100 fs/super.c:329
 deactivate_super+0x2bb/0x320 fs/super.c:360
 cleanup_mnt+0xbf/0x160 fs/namespace.c:1098
 __cleanup_mnt+0x16/0x20 fs/namespace.c:1105
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 get_signal+0x1558/0x1980 kernel/signal.c:2347
 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446689
Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f621e979da8 EFLAGS: 00000293 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00000000006dbc28 RCX: 0000000000446689
RDX: 0000000000446689 RSI: 000000000000000a RDI: 0000000020000180
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000006dbc2c
R13: 0030656c69662f2e R14: 65646f6d746f6f72 R15: 0000000000000000
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.274 msecs
kobject: '0:31' (0000000050d00699): fill_kobj_path: path = '/devices/virtual/bdi/0:31'
kobject: '0:32' (00000000d2d168d9): kobject_cleanup, parent           (null)
kobject: '0:31' (0000000050d00699): kobject_cleanup, parent           (null)
kobject: '0:32' (00000000d2d168d9): calling ktype release
kobject: '0:33' (00000000d76406a3): kobject_cleanup, parent           (null)
kobject: '0:28' (000000002da84317): calling ktype release
kobject: '0:29' (00000000e2434e73): kobject_cleanup, parent           (null)
kobject: '0:32': free name
kobject: '0:33' (00000000d76406a3): calling ktype release
kobject: '0:33': free name
kobject: '0:29' (00000000e2434e73): calling ktype release
kobject: '0:28': free name
kobject: '0:29': free name
kobject: '0:31' (0000000050d00699): calling ktype release
kobject: '0:28' (0000000080474e07): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:29' (0000000051f8f0a5): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:28' (0000000080474e07): kobject_uevent_env
kobject: '0:32' (0000000075558c25): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:33' (00000000c8dd3226): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:29' (0000000051f8f0a5): kobject_uevent_env
kobject: '0:33' (00000000c8dd3226): kobject_uevent_env
kobject: '0:31': free name
kobject: '0:28' (0000000080474e07): fill_kobj_path: path = '/devices/virtual/bdi/0:28'
kobject: '0:29' (0000000051f8f0a5): fill_kobj_path: path = '/devices/virtual/bdi/0:29'
kobject: '0:34' (000000008aa55f96): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:33' (00000000c8dd3226): fill_kobj_path: path = '/devices/virtual/bdi/0:33'
kobject: '0:31' (000000008e78fdc7): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:32' (0000000075558c25): kobject_uevent_env
kobject: '0:34' (000000008aa55f96): kobject_uevent_env
kobject: '0:32' (0000000075558c25): fill_kobj_path: path = '/devices/virtual/bdi/0:32'
kobject: '0:34' (000000008aa55f96): fill_kobj_path: path = '/devices/virtual/bdi/0:34'

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/11/01 09:08 upstream 59fc453b21f7 1f38e9ae .config console log report syz C ci-upstream-kasan-gce-root
2018/11/01 06:41 upstream 59fc453b21f7 1f38e9ae .config console log report ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.