INFO: task syz-executor.5:23019 blocked for more than 143 seconds. Not tainted 5.2.0+ #67 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28160 23019 9106 0x00000004 Call Trace: context_switch /kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 /kernel/sched/core.c:3880 schedule+0xa8/0x270 /kernel/sched/core.c:3944 rwsem_down_write_slowpath+0x708/0xf60 /kernel/locking/rwsem.c:1198 __down_write /kernel/locking/rwsem.c:1349 [inline] down_write+0x13c/0x150 /kernel/locking/rwsem.c:1485 unregister_netdevice_notifier+0x7e/0x390 /net/core/dev.c:1713 bcm_release+0x93/0x5e0 /net/can/bcm.c:1525 __sock_release+0xce/0x280 /net/socket.c:590 sock_close+0x1e/0x30 /net/socket.c:1268 __fput+0x2ff/0x890 /fs/file_table.c:280 ____fput+0x16/0x20 /fs/file_table.c:313 task_work_run+0x145/0x1c0 /kernel/task_work.c:113 tracehook_notify_resume /./include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 /arch/x86/entry/common.c:163 prepare_exit_to_usermode /arch/x86/entry/common.c:194 [inline] syscall_return_slowpath /arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 /arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413501 Code: 5f fe ff ff 31 c9 31 f6 41 b9 b0 20 41 00 41 b8 8c d6 65 00 ba 02 00 00 00 bf 28 38 44 00 ff 15 7d a1 24 00 85 c0 0f 85 37 fe ff 31 c9 31 f6 41 b9 b0 20 41 00 41 b8 90 d6 65 00 ba 03 00 00 RSP: 002b:00007ffe3a5c9870 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413501 RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000003 RBP: 0000000000000000 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffe3a5c9950 R11: 0000000000000293 R12: 000000000075bfc8 R13: 000000000006a727 R14: 0000000000760d60 R15: ffffffffffffffff Showing all locks held in the system: 4 locks held by kworker/u4:1/21: 1 lock held by khungtaskd/1053: #0: 0000000062a53f32 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e /kernel/locking/lockdep.c:5257 1 lock held by rsyslogd/8961: #0: 0000000010983291 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 /fs/file.c:801 2 locks held by getty/9051: #0: 00000000330e35ea (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 000000001155b745 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9052: #0: 0000000017bfec34 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 0000000045e46af7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9053: #0: 0000000055d55c7e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 0000000006761f3a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9054: #0: 00000000afb4961d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 0000000052d08972 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9055: #0: 00000000961827a7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 00000000e28590c5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9056: #0: 000000009b190909 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 00000000ba6aecb5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9057: #0: 00000000a8a3e265 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 00000000da1537e5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by syz-executor.5/23019: #0: 0000000051628f83 (&sb->s_type->i_mutex_key#12){+.+.}, at: inode_lock /./include/linux/fs.h:778 [inline] #0: 0000000051628f83 (&sb->s_type->i_mutex_key#12){+.+.}, at: __sock_release+0x89/0x280 /net/socket.c:589 #1: 000000009cbc87fa (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x390 /net/core/dev.c:1713 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1053 Comm: khungtaskd Not tainted 5.2.0+ #67 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+0x172/0x1f0 /lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 /lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b /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:146 [inline] check_hung_uninterruptible_tasks /kernel/hung_task.c:205 [inline] watchdog+0x9d0/0xef0 /kernel/hung_task.c:289 kthread+0x361/0x430 /kernel/kthread.c:255 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.2.0+ #67 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:hlock_class /kernel/locking/lockdep.c:175 [inline] RIP: 0010:mark_lock+0xce/0x11e0 /kernel/locking/lockdep.c:3568 Code: 0f b7 db be 08 00 00 00 48 89 d8 48 c1 f8 06 48 8d 3c c5 00 ba 53 8a e8 a0 0c 54 00 48 0f a3 1d e8 5a fb 08 0f 83 be 00 00 00 <48> 69 db b0 00 00 00 48 81 c3 20 be 53 8a 48 8d 7b 50 48 b8 00 00 RSP: 0018:ffff8880a9a37a08 EFLAGS: 00000047 RAX: 0000000000000001 RBX: 0000000000000072 RCX: ffffffff81585f10 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8a53ba08 RBP: ffff8880a9a37a58 R08: 1ffffffff14a7741 R09: fffffbfff14a7742 R10: fffffbfff14a7741 R11: ffffffff8a53ba0f R12: 0000000000000007 R13: ffff8880a9a2ce60 R14: dffffc0000000000 R15: ffff8880a9a2ce10 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a1a4e000 CR4: 00000000001406e0 Call Trace: mark_held_locks+0xa4/0xf0 /kernel/locking/lockdep.c:3285 __trace_hardirqs_on_caller /kernel/locking/lockdep.c:3314 [inline] lockdep_hardirqs_on+0x418/0x5d0 /kernel/locking/lockdep.c:3359 trace_hardirqs_on+0x67/0x240 /kernel/trace/trace_preemptirq.c:31 __local_bh_enable_ip+0x15a/0x270 /kernel/softirq.c:194 local_bh_enable /./include/linux/bottom_half.h:32 [inline] get_next_corpse /net/netfilter/nf_conntrack_core.c:2016 [inline] nf_ct_iterate_cleanup+0x217/0x4e0 /net/netfilter/nf_conntrack_core.c:2039 nf_conntrack_cleanup_net_list+0x7a/0x240 /net/netfilter/nf_conntrack_core.c:2226 nf_conntrack_pernet_exit+0x159/0x1a0 /net/netfilter/nf_conntrack_standalone.c:1151 ops_exit_list.isra.0+0xfc/0x150 /net/core/net_namespace.c:175 cleanup_net+0x4e2/0xa70 /net/core/net_namespace.c:594 process_one_work+0x9af/0x1740 /kernel/workqueue.c:2269 worker_thread+0x98/0xe40 /kernel/workqueue.c:2415 kthread+0x361/0x430 /kernel/kthread.c:255 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352