INFO: task syz-executor.4:12724 can't die for more than 143 seconds. task:syz-executor.4 state:D stack:29848 pid:12724 ppid: 12371 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 raw_init+0x296/0x340 net/can/raw.c:339 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3ca/0x740 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0xef/0x200 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1527 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f9995572c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000032bc0 RCX: 000000000045d5b9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007fffac14b46f R14: 00007f99955739c0 R15: 000000000118cf4c INFO: task syz-executor.4:12724 blocked for more than 143 seconds. Not tainted 5.9.0-rc2-next-20200828-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:29848 pid:12724 ppid: 12371 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 raw_init+0x296/0x340 net/can/raw.c:339 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3ca/0x740 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0xef/0x200 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1527 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f9995572c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000032bc0 RCX: 000000000045d5b9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007fffac14b46f R14: 00007f99955739c0 R15: 000000000118cf4c INFO: task syz-executor.4:12732 can't die for more than 144 seconds. task:syz-executor.4 state:D stack:29848 pid:12732 ppid: 12371 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 raw_init+0x296/0x340 net/can/raw.c:339 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3ca/0x740 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0xef/0x200 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1527 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f9995530c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000032bc0 RCX: 000000000045d5b9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118d0c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118d08c R13: 00007fffac14b46f R14: 00007f99955319c0 R15: 000000000118d08c INFO: task syz-executor.4:12732 blocked for more than 144 seconds. Not tainted 5.9.0-rc2-next-20200828-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:29848 pid:12732 ppid: 12371 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 raw_init+0x296/0x340 net/can/raw.c:339 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3ca/0x740 net/socket.c:1427 sock_create net/socket.c:1478 [inline] __sys_socket+0xef/0x200 net/socket.c:1520 __do_sys_socket net/socket.c:1529 [inline] __se_sys_socket net/socket.c:1527 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1527 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f9995530c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000032bc0 RCX: 000000000045d5b9 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118d0c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118d08c R13: 00007fffac14b46f R14: 00007f99955319c0 R15: 000000000118d08c Showing all locks held in the system: 4 locks held by kworker/u4:1/21: 1 lock held by khungtaskd/1172: #0: ffffffff89c67640 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5825 1 lock held by in:imklog/6560: #0: ffff8880a1ed06b0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 1 lock held by syz-executor.4/12724: #0: ffffffff8a879430 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 1 lock held by syz-executor.4/12732: #0: ffffffff8a879430 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc2-next-20200828-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:339 kthread+0x3b5/0x4a0 kernel/kthread.c:292 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: 21 Comm: kworker/u4:1 Not tainted 5.9.0-rc2-next-20200828-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:653 [inline] RIP: 0010:__local_bh_disable_ip+0x9c/0x190 kernel/softirq.c:136 Code: 83 3d 67 69 6f 08 00 0f 84 c9 00 00 00 fa 66 0f 1f 44 00 00 65 01 1d 03 29 bb 7e 65 8b 05 fc 28 bb 7e 48 31 d8 f6 c4 ff 74 4c <48> c7 c0 c8 3e b6 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 RSP: 0018:ffffc90000dd7b68 EFLAGS: 00000002 RAX: 0000000080000200 RBX: 0000000000000200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000200 RDI: ffff8880a9028e38 RBP: 0000000000000286 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000001e6c R11: 0000000000000001 R12: ffffffff867e11fa R13: 0000000000001e6c R14: 0000000000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7f90266000 CR3: 000000009374d000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: local_bh_disable include/linux/bottom_half.h:19 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2203 [inline] nf_ct_iterate_cleanup+0xef/0x330 net/netfilter/nf_conntrack_core.c:2249 nf_conntrack_cleanup_net_list+0x81/0x250 net/netfilter/nf_conntrack_core.c:2436 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294