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INFO: task hung in cleanup_net (5)

Status: auto-closed as invalid on 2021/09/03 11:33
Subsystems: net
[Documentation on labels]
First crash: 1117d, last: 1071d
▶ ▼ Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cleanup_net (2) net 2 1826d 1826d 0/26 closed as invalid on 2019/05/08 13:05
android-44 INFO: task hung in cleanup_net 10 1780d 1822d 0/2 auto-closed as invalid on 2019/10/25 08:38
upstream INFO: task hung in cleanup_net net 1 2331d 2319d 3/26 fixed on 2018/01/03 02:35
linux-4.19 INFO: task hung in cleanup_net 1 1445d 1445d 0/1 auto-closed as invalid on 2020/09/08 00:00
linux-4.14 INFO: task hung in cleanup_net C inconclusive 23 833d 1839d 0/1 upstream: reported C repro on 2019/04/13 10:16
upstream INFO: task hung in cleanup_net (3) net 1 1760d 1760d 0/26 auto-closed as invalid on 2019/10/25 14:21
android-49 INFO: task hung in cleanup_net 4 1830d 1838d 0/3 auto-closed as invalid on 2019/10/18 21:44
upstream INFO: task hung in cleanup_net (4) net 2 1344d 1349d 0/26 auto-closed as invalid on 2020/11/17 15:39
android-414 INFO: task hung in cleanup_net C 45 1698d 1841d 0/1 public: reported C repro on 2019/04/11 00:00
android-49 INFO: task hung in cleanup_net (2) 1 1614d 1614d 0/3 auto-closed as invalid on 2020/03/23 02:35
upstream INFO: task hung in cleanup_net (6) net 1 298d 298d 0/26 auto-obsoleted due to no activity on 2023/09/30 00:07

Sample crash report:
INFO: task kworker/u4:5:168 blocked for more than 143 seconds.
      Not tainted 5.13.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:5    state:D stack:20696 pid:  168 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0xb98/0x1120 kernel/sched/core.c:5147
 schedule+0x14b/0x200 kernel/sched/core.c:5226
 rwsem_down_read_slowpath+0x58f/0x9f0 kernel/locking/rwsem.c:992
 __down_read_common+0xaa/0x450 kernel/locking/rwsem.c:1213
 cleanup_net+0xf0/0xc60 net/core/net_namespace.c:557
 process_one_work+0x833/0x10c0 kernel/workqueue.c:2275
 worker_thread+0xac1/0x1300 kernel/workqueue.c:2421
 kthread+0x39a/0x3c0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task syz-executor.2:26295 blocked for more than 144 seconds.
      Not tainted 5.13.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25552 pid:26295 ppid: 16480 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0xb98/0x1120 kernel/sched/core.c:5147
 schedule+0x14b/0x200 kernel/sched/core.c:5226
 rwsem_down_write_slowpath+0xe52/0x1590 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x165/0x170 kernel/locking/rwsem.c:1407
 unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
 raw_release+0x5f/0x770 net/can/raw.c:354
 __sock_release net/socket.c:599 [inline]
 sock_close+0xd8/0x260 net/socket.c:1258
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x736/0x23d0 kernel/exit.c:826
 do_group_exit+0x168/0x2d0 kernel/exit.c:923
 get_signal+0x1770/0x2180 kernel/signal.c:2818
 arch_do_signal_or_restart+0x8e/0x6c0 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+0xac/0x200 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
RSP: 002b:00007f4b51d54218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68
RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c
R13: 00007ffcd143780f R14: 00007f4b51d54300 R15: 0000000000022000
INFO: task syz-executor.2:26366 blocked for more than 145 seconds.
      Not tainted 5.13.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25552 pid:26366 ppid: 16480 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0xb98/0x1120 kernel/sched/core.c:5147
 schedule+0x14b/0x200 kernel/sched/core.c:5226
 rwsem_down_write_slowpath+0xe52/0x1590 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x165/0x170 kernel/locking/rwsem.c:1407
 unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
 raw_release+0x5f/0x770 net/can/raw.c:354
 __sock_release net/socket.c:599 [inline]
 sock_close+0xd8/0x260 net/socket.c:1258
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x736/0x23d0 kernel/exit.c:826
 do_group_exit+0x168/0x2d0 kernel/exit.c:923
 get_signal+0x1770/0x2180 kernel/signal.c:2818
 arch_do_signal_or_restart+0x8e/0x6c0 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+0xac/0x200 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
RSP: 002b:00007f4b51d54218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68
RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c
R13: 00007ffcd143780f R14: 00007f4b51d54300 R15: 0000000000022000
INFO: task syz-executor.3:26380 blocked for more than 146 seconds.
      Not tainted 5.13.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:25264 pid:26380 ppid: 17331 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0xb98/0x1120 kernel/sched/core.c:5147
 schedule+0x14b/0x200 kernel/sched/core.c:5226
 rwsem_down_write_slowpath+0xe52/0x1590 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x165/0x170 kernel/locking/rwsem.c:1407
 unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
 raw_release+0x5f/0x770 net/can/raw.c:354
 __sock_release net/socket.c:599 [inline]
 sock_close+0xd8/0x260 net/socket.c:1258
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x736/0x23d0 kernel/exit.c:826
 do_group_exit+0x168/0x2d0 kernel/exit.c:923
 get_signal+0x1770/0x2180 kernel/signal.c:2818
 arch_do_signal_or_restart+0x8e/0x6c0 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+0xac/0x200 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
RSP: 002b:00007fbfac505218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68
RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c
R13: 00007fff8c7afadf R14: 00007fbfac505300 R15: 0000000000022000
INFO: task syz-executor.2:26434 blocked for more than 146 seconds.
      Not tainted 5.13.0-rc2-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25648 pid:26434 ppid: 16480 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4339 [inline]
 __schedule+0xb98/0x1120 kernel/sched/core.c:5147
 schedule+0x14b/0x200 kernel/sched/core.c:5226
 rwsem_down_write_slowpath+0xe52/0x1590 kernel/locking/rwsem.c:1106
 __down_write_common kernel/locking/rwsem.c:1261 [inline]
 __down_write kernel/locking/rwsem.c:1270 [inline]
 down_write+0x165/0x170 kernel/locking/rwsem.c:1407
 unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
 raw_release+0x5f/0x770 net/can/raw.c:354
 __sock_release net/socket.c:599 [inline]
 sock_close+0xd8/0x260 net/socket.c:1258
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x736/0x23d0 kernel/exit.c:826
 do_group_exit+0x168/0x2d0 kernel/exit.c:923
 get_signal+0x1770/0x2180 kernel/signal.c:2818
 arch_do_signal_or_restart+0x8e/0x6c0 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+0xac/0x200 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
RSP: 002b:00007f4b51d54218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68
RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c
R13: 00007ffcd143780f R14: 00007f4b51d54300 R15: 0000000000022000

Showing all locks held in the system:
3 locks held by kworker/u4:5/168:
 #0: ffff88814012b138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 kernel/workqueue.c:2248
 #1: ffffc900015efd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 kernel/workqueue.c:2250
 #2: ffffffff8df1e730 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf0/0xc60 net/core/net_namespace.c:557
1 lock held by khungtaskd/1631:
 #0: ffffffff8cf15c40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151
1 lock held by in:imklog/8096:
 #0: ffff888020edf4f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:974
2 locks held by agetty/8100:
 #0: ffff8880200f2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:267
 #1: ffffc90000f192e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6c3/0x1cf0 drivers/tty/n_tty.c:2179
3 locks held by kworker/1:19/16545:
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 kernel/workqueue.c:2248
 #1: ffffc9000168fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 kernel/workqueue.c:2250
 #2: ffffffff8df2a4e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:250
2 locks held by syz-executor.2/26295:
 #0: ffff88806c0ba190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline]
 #0: ffff88806c0ba190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release net/socket.c:598 [inline]
 #0: ffff88806c0ba190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: sock_close+0x94/0x260 net/socket.c:1258
 #1: ffffffff8df1e730 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
2 locks held by syz-executor.2/26366:
 #0: ffff88806c23e6d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline]
 #0: ffff88806c23e6d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release net/socket.c:598 [inline]
 #0: ffff88806c23e6d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: sock_close+0x94/0x260 net/socket.c:1258
 #1: ffffffff8df1e730 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
2 locks held by syz-executor.3/26380:
 #0: ffff88806235f690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline]
 #0: ffff88806235f690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release net/socket.c:598 [inline]
 #0: ffff88806235f690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: sock_close+0x94/0x260 net/socket.c:1258
 #1: ffffffff8df1e730 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
2 locks held by syz-executor.2/26434:
 #0: ffff8880620a26d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline]
 #0: ffff8880620a26d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release net/socket.c:598 [inline]
 #0: ffff8880620a26d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: sock_close+0x94/0x260 net/socket.c:1258
 #1: ffffffff8df1e730 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949
2 locks held by syz-executor.2/15394:
 #0: ffffffff8df1e730 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5e0 net/core/net_namespace.c:470
 #1: ffffffff8df2a4e8 (rtnl_mutex){+.+.}-{3:3}, at: ip_fib_net_exit+0x25/0x380 net/ipv4/fib_frontend.c:1544
1 lock held by syz-executor.0/15404:
 #0: ffffffff8df2a4e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline]
 #0: ffffffff8df2a4e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3c/0x130 drivers/net/tun.c:3397
1 lock held by syz-executor.1/15419:

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

NMI backtrace for cpu 1
CPU: 1 PID: 1631 Comm: khungtaskd Not tainted 5.13.0-rc2-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+0x202/0x31e lib/dump_stack.c:120
 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x191/0x2f0 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+0xcfb/0xd40 kernel/hung_task.c:294
 kthread+0x39a/0x3c0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15419 Comm: syz-executor.1 Not tainted 5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kasan_check_range+0x2/0x2f0 mm/kasan/generic.c:185
Code: 48 89 c7 e8 50 93 f9 07 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc cc 41 57 <41> 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 0d 02 00 00 48 89 fb 48
RSP: 0018:ffffc900000076f0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 000000000000005a RCX: ffffffff81611c20
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9026cd88
RBP: ffffc90000007a90 R08: dffffc0000000000 R09: fffffbfff204d9b1
R10: fffffbfff204d9b1 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000002 R14: 0000000000000002 R15: ffff8880293a0a68
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4eb388c000 CR3: 000000000cc8e000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:199 [inline]
 check_wait_context kernel/locking/lockdep.c:4600 [inline]
 __lock_acquire+0x8b0/0x6040 kernel/locking/lockdep.c:4852
 lock_acquire+0x17f/0x720 kernel/locking/lockdep.c:5512
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xb3/0x100 kernel/locking/spinlock.c:159
 debug_object_deactivate+0x61/0x400 lib/debugobjects.c:730
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate kernel/time/hrtimer.c:481 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1505 [inline]
 __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1601
 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:647
RIP: 0010:lock_acquire+0x1f6/0x720 kernel/locking/lockdep.c:5516
Code: f6 84 24 a1 00 00 00 02 0f 85 8d 02 00 00 f7 c3 00 02 00 00 49 bd 00 00 00 00 00 fc ff df 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 4b c7 44 3d 09 00 00 00 00 43 c7 44 3d
RSP: 0018:ffffc9000381f160 EFLAGS: 00000206
RAX: 1ffff92000703e40 RBX: 0000000000000246 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000
RBP: ffffc9000381f2d8 R08: dffffc0000000000 R09: fffffbfff204d9c0
R10: fffffbfff204d9c0 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000703e34
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 nf_conntrack_lock net/netfilter/nf_conntrack_core.c:95 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:2215 [inline]
 nf_ct_iterate_cleanup+0xf8/0x3f0 net/netfilter/nf_conntrack_core.c:2260
 nf_ct_iterate_cleanup_net+0x17a/0x210 net/netfilter/nf_conntrack_core.c:2348
 masq_device_event+0x9b/0xd0 net/netfilter/nf_nat_masquerade.c:88
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:410
 call_netdevice_notifiers_info net/core/dev.c:2121 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2133 [inline]
 call_netdevice_notifiers net/core/dev.c:2147 [inline]
 dev_close_many+0x38b/0x540 net/core/dev.c:1722
 unregister_netdevice_many+0x53a/0x1980 net/core/dev.c:10983
 unregister_netdevice_queue+0x2e6/0x350 net/core/dev.c:10940
 unregister_netdevice include/linux/netdevice.h:2969 [inline]
 __tun_detach+0x64c/0x1d40 drivers/net/tun.c:670
 tun_detach drivers/net/tun.c:687 [inline]
 tun_chr_close+0xed/0x130 drivers/net/tun.c:3397
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x736/0x23d0 kernel/exit.c:826
 do_group_exit+0x168/0x2d0 kernel/exit.c:923
 get_signal+0x1770/0x2180 kernel/signal.c:2818
 arch_do_signal_or_restart+0x8e/0x6c0 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+0xac/0x200 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: Unable to access opcode bytes at RIP 0x4665af.
RSP: 002b:00007f4755797188 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 000000000056bf60 RCX: 00000000004665d9
RDX: 9999999999999999 RSI: 0000000000000000 RDI: 00000000e1004d7c
RBP: 00000000004bfcb9 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffcc66fefcf R14: 00007f4755797300 R15: 0000000000022000

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/19 23:01 upstream 293837b9ac8d a343ba6b .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in cleanup_net
2021/04/10 08:11 upstream d4961772226d bfeda1b1 .config console log report info ci-upstream-kasan-gce INFO: task hung in cleanup_net
2021/04/04 08:12 upstream 2023a53bdf41 6a81331a .config console log report info ci-upstream-kasan-gce INFO: task hung in cleanup_net
* Struck through repros no longer work on HEAD.