INFO: task syz-executor.5:24025 blocked for more than 140 seconds. Not tainted 4.19.37 #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29496 24025 9834 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x813/0x1d00 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:573 [inline] rwsem_down_write_failed+0x774/0xcc0 kernel/locking/rwsem-xadd.c:602 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 bcm_init+0x1a8/0x220 net/can/bcm.c:1502 can_create+0x28a/0x4b0 net/can/af_can.c:183 __sock_create+0x3e6/0x750 net/socket.c:1276 sock_create net/socket.c:1316 [inline] __sys_socket+0x103/0x220 net/socket.c:1346 __do_sys_socket net/socket.c:1355 [inline] __se_sys_socket net/socket.c:1353 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1353 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: 66 44 0f ef e4 66 44 0f ef ed 66 44 0f ef f6 66 44 0f ef ff 66 45 0f 38 dc c0 66 45 0f 38 dc c9 66 45 0f 38 dc d2 66 45 0f 38 db 66 45 0f 38 dc e4 66 45 0f 38 dc ed 66 45 0f 38 dc f6 66 45 RSP: 002b:00007f2bb3369c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2bb336a6d4 R13: 00000000004c739e R14: 00000000004dd070 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1032: #0: 0000000061aa7ce9 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4435 2 locks held by rs:main Q:Reg/7719: #0: 0000000021802698 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 #1: 00000000fbeaf145 (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2764 [inline] #1: 00000000fbeaf145 (sb_writers#4){.+.+}, at: vfs_write+0x429/0x560 fs/read_write.c:548 1 lock held by rsyslogd/7721: #0: 00000000db3c18ca (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/7844: #0: 00000000d3f066b8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000f5a39129 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7845: #0: 0000000029ac8655 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000d78aff37 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7846: #0: 000000001e12171a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 0000000082065210 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7847: #0: 000000001e541fda (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000cc5f8b26 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7848: #0: 000000004650aca5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000b6e0e3e5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7849: #0: 00000000d9987516 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000dbe7587c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 3 locks held by kworker/u4:0/15049: 2 locks held by syz-executor.5/16491: #0: 00000000623fb1f4 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:738 [inline] #0: 00000000623fb1f4 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2b0 net/socket.c:578 #1: 00000000fcd9f4ed (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x3a0 net/core/dev.c:1711 2 locks held by getty/18752: #0: 000000000cda7d5f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000005206b1bf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.5/24025: #0: 00000000fcd9f4ed (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1032 Comm: khungtaskd Not tainted 4.19.37 #5 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+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15049 Comm: kworker/u4:0 Not tainted 4.19.37 #5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:validate_chain kernel/locking/lockdep.c:2385 [inline] RIP: 0010:__lock_acquire+0x880/0x48f0 kernel/locking/lockdep.c:3411 Code: 00 00 00 85 c0 4c 8b 54 24 68 0f 84 ec 08 00 00 48 8b 94 24 80 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e 35 2c 00 00 41 8b 42 20 25 00 80 04 00 3d RSP: 0018:ffff8880593e78a0 EFLAGS: 00000802 RAX: 0000000000000000 RBX: 00000000c5290949 RCX: 00000000e7e080cd RDX: 1ffff1100a6fbd83 RSI: ffff8880537deb80 RDI: 0000000000000000 RBP: ffff8880593e7a68 R08: 0000000000000001 R09: 0000000000000003 R10: ffff8880537debf8 R11: b57014516158ac46 R12: 5a5f6a4650a7fc2d R13: 0000000000000000 R14: ffff8880537de300 R15: ffff8880537dec10 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a5cf0000 CR4: 00000000001426f0 Call Trace: lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3900 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:144 spin_lock include/linux/spinlock.h:329 [inline] nf_conntrack_lock+0x17/0x70 net/netfilter/nf_conntrack_core.c:95 get_next_corpse net/netfilter/nf_conntrack_core.c:1882 [inline] nf_ct_iterate_cleanup+0x1d7/0x4e0 net/netfilter/nf_conntrack_core.c:1916 nf_conntrack_cleanup_net_list+0x7a/0x250 net/netfilter/nf_conntrack_core.c:2103 nf_conntrack_pernet_exit+0x11d/0x170 net/netfilter/nf_conntrack_standalone.c:663 ops_exit_list.isra.0+0x105/0x160 net/core/net_namespace.c:156 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552 process_one_work+0x98e/0x1760 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413