syzbot


INFO: task hung in default_device_exit_batch

Status: auto-closed as invalid on 2020/08/28 19:07
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 847d, last: 847d

Sample crash report:
INFO: task kworker/u4:5:8520 blocked for more than 143 seconds.
      Not tainted 5.7.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:5    D27776  8520      2 0x80004000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:3367 [inline]
 __schedule+0x937/0x1ff0 kernel/sched/core.c:4083
 schedule+0xd0/0x2a0 kernel/sched/core.c:4158
 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1874
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138
 __flush_work+0x4fd/0xa80 kernel/workqueue.c:3045
 flush_all_backlogs net/core/dev.c:5537 [inline]
 rollback_registered_many+0x562/0xe70 net/core/dev.c:8823
 unregister_netdevice_many.part.0+0x16/0x1e0 net/core/dev.c:10000
 unregister_netdevice_many net/core/dev.c:9999 [inline]
 default_device_exit_batch+0x311/0x3d0 net/core/dev.c:10483
 ops_exit_list.isra.0+0x103/0x150 net/core/net_namespace.c:189
 cleanup_net+0x511/0xa50 net/core/net_namespace.c:603
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351
INFO: task syz-executor.2:8753 blocked for more than 143 seconds.
      Not tainted 5.7.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D26952  8753   7232 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3367 [inline]
 __schedule+0x937/0x1ff0 kernel/sched/core.c:4083
 schedule+0xd0/0x2a0 kernel/sched/core.c:4158
 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1874
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138
 __flush_work+0x4fd/0xa80 kernel/workqueue.c:3045
 lru_add_drain_all+0x3ee/0x5b0 mm/swap.c:759
 invalidate_bdev+0x96/0xd0 fs/block_dev.c:97
 __loop_clr_fd+0x38a/0xd80 drivers/block/loop.c:1162
 loop_clr_fd drivers/block/loop.c:1259 [inline]
 lo_ioctl+0x2b4/0x1410 drivers/block/loop.c:1628
 __blkdev_driver_ioctl block/ioctl.c:322 [inline]
 blkdev_ioctl+0x25b/0x660 block/ioctl.c:718
 block_ioctl+0xf9/0x140 fs/block_dev.c:2005
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:771
 __do_sys_ioctl fs/ioctl.c:780 [inline]
 __se_sys_ioctl fs/ioctl.c:778 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:778
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c937
Code: Bad RIP value.
RSP: 002b:00007f11423d09d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045c937
RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000004
RBP: 0000000000000009 R08: 0000000000000000 R09: 000000000000000c
R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000000005
R13: 0000000000000005 R14: 00000000004c1b95 R15: 00007f11423d16d4
INFO: task syz-executor.2:8784 blocked for more than 144 seconds.
      Not tainted 5.7.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28392  8784   7232 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3367 [inline]
 __schedule+0x937/0x1ff0 kernel/sched/core.c:4083
 schedule+0xd0/0x2a0 kernel/sched/core.c:4158
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217
 __mutex_lock_common kernel/locking/mutex.c:1033 [inline]
 __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103
 __blkdev_get+0x179/0x1530 fs/block_dev.c:1600
 blkdev_get+0x41/0x2b0 fs/block_dev.c:1748
 blkdev_open+0x21d/0x2b0 fs/block_dev.c:1887
 do_dentry_open+0x4ba/0x1290 fs/open.c:797
 do_open fs/namei.c:3229 [inline]
 path_openat+0x1e59/0x27d0 fs/namei.c:3346
 do_filp_open+0x192/0x260 fs/namei.c:3373
 do_sys_openat2+0x585/0x7d0 fs/open.c:1148
 do_sys_open+0xc3/0x140 fs/open.c:1164
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x416861
Code: Bad RIP value.
RSP: 002b:00007f114238e9d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000005098c0 RCX: 0000000000416861
RDX: 00007f114238ebba RSI: 0000000000000002 RDI: 00007f114238ebb0
RBP: 000000000078c040 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000293 R12: 00000000ffffffff
R13: 0000000000000c29 R14: 00000000004c1b95 R15: 00007f114238f6d4
INFO: task syz-executor.3:8779 blocked for more than 145 seconds.
      Not tainted 5.7.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D26736  8779   7332 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3367 [inline]
 __schedule+0x937/0x1ff0 kernel/sched/core.c:4083
 schedule+0xd0/0x2a0 kernel/sched/core.c:4158
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217
 __mutex_lock_common kernel/locking/mutex.c:1033 [inline]
 __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103
 rtnl_lock net/core/rtnetlink.c:72 [inline]
 rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5451
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362
 ___sys_sendmsg+0x100/0x170 net/socket.c:2416
 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca69
Code: Bad RIP value.
RSP: 002b:00007f3c03fc3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000500fc0 RCX: 000000000045ca69
RDX: 0000000000000000 RSI: 0000000020000800 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a05 R14: 00000000004cce1d R15: 00007f3c03fc46d4

Showing all locks held in the system:
1 lock held by khungtaskd/1138:
 #0: ffffffff899bea80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5754
3 locks held by kworker/1:2/2687:
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline]
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
 #0: ffff88821532c538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2239
 #1: ffffc90007e17dc0 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243
 #2: ffffffff8a586988 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4584
2 locks held by systemd-udevd/4120:
 #0: ffff888088cc4240 (&bdev->bd_mutex){+.+.}-{3:3}, at: __blkdev_get+0x179/0x1530 fs/block_dev.c:1600
 #1: ffffffff8a08f588 (loop_ctl_mutex){+.+.}-{3:3}, at: lo_open+0x19/0xd0 drivers/block/loop.c:1819
1 lock held by in:imklog/6731:
 #0: ffff88809d503370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826
5 locks held by kworker/u4:5/8520:
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:226 [inline]
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline]
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline]
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline]
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
 #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2239
 #1: ffffc90001b07dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243
 #2: ffffffff8a57a9f0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565
 #3: ffffffff8a586988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:10436 [inline]
 #3: ffffffff8a586988 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xea/0x3d0 net/core/dev.c:10474
 #4: ffffffff89979a70 (cpu_hotplug_lock){++++}-{0:0}, at: get_online_cpus include/linux/cpu.h:143 [inline]
 #4: ffffffff89979a70 (cpu_hotplug_lock){++++}-{0:0}, at: flush_all_backlogs net/core/dev.c:5530 [inline]
 #4: ffffffff89979a70 (cpu_hotplug_lock){++++}-{0:0}, at: rollback_registered_many+0x45b/0xe70 net/core/dev.c:8823
2 locks held by syz-executor.2/8753:
 #0: ffffffff8a08f588 (loop_ctl_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x86/0xd80 drivers/block/loop.c:1127
 #1: ffffffff89a3ecc8 (lock#7){+.+.}-{3:3}, at: lru_add_drain_all+0x59/0x5b0 mm/swap.c:730
1 lock held by syz-executor.2/8784:
 #0: ffff888088cc4240 (&bdev->bd_mutex){+.+.}-{3:3}, at: __blkdev_get+0x179/0x1530 fs/block_dev.c:1600
2 locks held by systemd-udevd/8751:
 #0: ffff888088cb7280 (&bdev->bd_mutex){+.+.}-{3:3}, at: __blkdev_put+0xfc/0x6f0 fs/block_dev.c:1905
 #1: ffffffff8a08f588 (loop_ctl_mutex){+.+.}-{3:3}, at: lo_release+0x1a/0x1f0 drivers/block/loop.c:1838
1 lock held by syz-executor.3/8779:
 #0: ffffffff8a586988 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8a586988 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5451

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

NMI backtrace for cpu 1
CPU: 1 PID: 1138 Comm: khungtaskd Not tainted 5.7.0-rc7-syzkaller #0
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+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xa8c/0x1010 kernel/hung_task.c:289
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8708 Comm: syz-executor.1 Not tainted 5.7.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline]
RIP: 0010:lock_is_held_type+0x262/0x350 kernel/locking/lockdep.c:4973
Code: 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 c2 00 00 00 48 83 3d 37 05 3c 08 00 74 32 48 8b 7c 24 10 57 9d <0f> 1f 44 00 00 48 83 c4 18 44 89 e0 5b 5d 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90005187d68 EFLAGS: 00000282
RAX: 1ffffffff132980c RBX: ffff888059eda240 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 1ffff1100b3db560 RDI: 0000000000000282
RBP: ffff888059eda240 R08: 0000000000000001 R09: ffffed1011c3f861
R10: ffff88808e1fc307 R11: ffffed1011c3f860 R12: 0000000000000000
R13: ffff88808e1fc160 R14: ffff888059edab00 R15: ffffffff899be9c0
FS:  0000000001970940(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005584fd37ec38 CR3: 000000008efb2000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_is_held include/linux/lockdep.h:406 [inline]
 ___might_sleep+0x1fc/0x2b0 kernel/sched/core.c:6766
 io_ring_ctx_wait_and_kill+0xa9/0x5f0 fs/io_uring.c:7323
 io_uring_release+0x3e/0x50 fs/io_uring.c:7345
 __fput+0x33e/0x880 fs/file_table.c:280
 task_work_run+0xf4/0x1b0 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x416661
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fffea660490 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000416661
RDX: 0000000000000000 RSI: 000000000000085e RDI: 0000000000000005
RBP: 0000000000000001 R08: 000000006c5ae85e R09: 000000006c5ae862
R10: 00007fffea660580 R11: 0000000000000293 R12: 000000000078c900
R13: 000000000078c900 R14: ffffffffffffffff R15: 000000000078bfac

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-selinux-root 2020/05/30 19:07 upstream 86852175b016 6f3e1c7c .config log report
* Struck through repros no longer work on HEAD.