[ OK ] Started Serial Getty on ttyS0. [ OK ] Started System Logging Service. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Started OpenBSD Secure Shell server. [ 48.123871][ T6643] sshd (6643) used greatest stack depth: 23544 bytes left Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.51' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 496.826098][ T6871] IPVS: ftp: loaded support on port[0] = 21 executing program [ 496.871876][ T6892] netlink: 396 bytes leftover after parsing attributes in process `syz-executor574'. [ 496.882512][ T6892] netlink: 68 bytes leftover after parsing attributes in process `syz-executor574'. [ 496.900081][ T6893] netlink: 396 bytes leftover after parsing attributes in process `syz-executor574'. [ 496.910094][ T6893] netlink: 68 bytes leftover after parsing attributes in process `syz-executor574'. [ 657.322745][ T1175] INFO: task kworker/0:0:6863 blocked for more than 143 seconds. [ 657.330591][ T1175] Not tainted 5.9.0-rc6-syzkaller #0 [ 657.340512][ T1175] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 657.350167][ T1175] task:kworker/0:0 state:D stack:29288 pid: 6863 ppid: 2 flags:0x00004000 [ 657.360676][ T1175] Workqueue: ipv6_addrconf addrconf_verify_work [ 657.367886][ T1175] Call Trace: [ 657.371274][ T1175] __schedule+0xec9/0x2280 [ 657.376967][ T1175] ? io_schedule_timeout+0x140/0x140 [ 657.384981][ T1175] ? lockdep_hardirqs_on_prepare+0x354/0x530 [ 657.391193][ T1175] ? _raw_spin_unlock_irq+0x1f/0x80 [ 657.398045][ T1175] ? lockdep_hardirqs_on+0x53/0x100 [ 657.404125][ T1175] schedule+0xd0/0x2a0 [ 657.408290][ T1175] schedule_preempt_disabled+0xf/0x20 [ 657.414991][ T1175] __mutex_lock+0x3e2/0x10e0 [ 657.419716][ T1175] ? addrconf_verify_work+0xa/0x20 [ 657.426108][ T1175] ? mutex_lock_io_nested+0xf60/0xf60 [ 657.431495][ T1175] ? lock_release+0x8f0/0x8f0 [ 657.437370][ T1175] ? lock_downgrade+0x830/0x830 [ 657.442241][ T1175] ? _raw_spin_unlock_irq+0x1f/0x80 [ 657.448686][ T1175] ? lock_is_held_type+0xbb/0xf0 [ 657.454427][ T1175] addrconf_verify_work+0xa/0x20 [ 657.459562][ T1175] process_one_work+0x94c/0x1670 [ 657.465976][ T1175] ? lock_release+0x8f0/0x8f0 [ 657.470657][ T1175] ? pwq_dec_nr_in_flight+0x320/0x320 [ 657.477297][ T1175] ? rwlock_bug.part.0+0x90/0x90 [ 657.482247][ T1175] ? lockdep_hardirqs_off+0x96/0xd0 [ 657.488728][ T1175] worker_thread+0x64c/0x1120 [ 657.494276][ T1175] ? __kthread_parkme+0x13f/0x1e0 [ 657.499308][ T1175] ? process_one_work+0x1670/0x1670 [ 657.505778][ T1175] kthread+0x3b5/0x4a0 [ 657.509886][ T1175] ? __kthread_bind_mask+0xc0/0xc0 [ 657.518288][ T1175] ret_from_fork+0x1f/0x30 [ 657.523663][ T1175] [ 657.523663][ T1175] Showing all locks held in the system: [ 657.531426][ T1175] 1 lock held by khungtaskd/1175: [ 657.537731][ T1175] #0: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [ 657.548797][ T1175] 1 lock held by in:imklog/6564: [ 657.554679][ T1175] #0: ffff888096c95df0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 [ 657.565993][ T1175] 3 locks held by kworker/0:0/6863: [ 657.571194][ T1175] #0: ffff888214dfb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 [ 657.583421][ T1175] #1: ffffc90000f07da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 [ 657.594648][ T1175] #2: ffffffff8b14d648 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 [ 657.605112][ T1175] 1 lock held by syz-executor574/6893: [ 657.610690][ T1175] [ 657.614190][ T1175] ============================================= [ 657.614190][ T1175] [ 657.622931][ T1175] NMI backtrace for cpu 0 [ 657.627272][ T1175] CPU: 0 PID: 1175 Comm: khungtaskd Not tainted 5.9.0-rc6-syzkaller #0 [ 657.635498][ T1175] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 657.645545][ T1175] Call Trace: [ 657.648988][ T1175] dump_stack+0x198/0x1fd [ 657.653330][ T1175] nmi_cpu_backtrace.cold+0x70/0xb1 [ 657.658735][ T1175] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 657.664368][ T1175] nmi_trigger_cpumask_backtrace+0x1b3/0x223 [ 657.670391][ T1175] watchdog+0xd7d/0x1000 [ 657.674637][ T1175] ? reset_hung_task_detector+0x30/0x30 [ 657.680193][ T1175] kthread+0x3b5/0x4a0 [ 657.684260][ T1175] ? __kthread_bind_mask+0xc0/0xc0 [ 657.689372][ T1175] ret_from_fork+0x1f/0x30 [ 657.694011][ T1175] Sending NMI from CPU 0 to CPUs 1: [ 657.700898][ C1] NMI backtrace for cpu 1 [ 657.700905][ C1] CPU: 1 PID: 6893 Comm: syz-executor574 Not tainted 5.9.0-rc6-syzkaller #0 [ 657.700912][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 657.700916][ C1] RIP: 0010:lock_release+0x465/0x8f0 [ 657.700927][ C1] Code: 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 fe 02 00 00 41 8b 84 24 e4 08 00 00 83 e8 01 66 85 c0 41 89 84 24 e4 08 00 00 <0f> 85 db 01 00 00 48 c7 c0 a8 6b fc 89 48 ba 00 00 00 00 00 fc ff [ 657.700931][ C1] RSP: 0018:ffffc900055f6c80 EFLAGS: 00000046 [ 657.700939][ C1] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 [ 657.700944][ C1] RDX: 0000000000000000 RSI: ffff88809ec1ba68 RDI: ffff888093272da4 [ 657.700949][ C1] RBP: 1ffff92000abed92 R08: 0000000000000001 R09: ffff888093272da0 [ 657.700954][ C1] R10: fffffbfff16b2cc9 R11: 0000000000000000 R12: ffff8880932724c0 [ 657.700959][ C1] R13: 0000000000000001 R14: ffffffff868a9b7e R15: ffff8880932724c0 [ 657.700965][ C1] FS: 000000000086c880(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 [ 657.700970][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 657.700975][ C1] CR2: 00007fc492792028 CR3: 00000000a8a30000 CR4: 00000000001506e0 [ 657.700980][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 657.700985][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 657.700988][ C1] Call Trace: [ 657.700991][ C1] ? lock_downgrade+0x830/0x830 [ 657.700995][ C1] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 657.700999][ C1] ? tcf_idr_check_alloc+0x78/0x3b0 [ 657.701002][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 657.701006][ C1] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 657.701010][ C1] ? mutex_lock_io_nested+0xf60/0xf60 [ 657.701014][ C1] __mutex_unlock_slowpath+0x81/0x610 [ 657.701017][ C1] ? __radix_tree_lookup+0x1bc/0x290 [ 657.701021][ C1] ? wait_for_completion+0x260/0x260 [ 657.701025][ C1] tcf_idr_check_alloc+0x29e/0x3b0 [ 657.701029][ C1] tcf_police_init+0x347/0x13a0 [ 657.701032][ C1] ? tcf_police_cleanup+0x60/0x60 [ 657.701036][ C1] ? find_held_lock+0x2d/0x110 [ 657.701039][ C1] ? tc_lookup_action_n+0xcd/0xf0 [ 657.701042][ C1] tcf_action_init_1+0x1a3/0x990 [ 657.701051][ C1] ? tcf_action_dump_old+0x80/0x80 [ 657.701055][ C1] ? lock_acquire+0x1f3/0xaf0 [ 657.701058][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701062][ C1] ? find_held_lock+0x2d/0x110 [ 657.701065][ C1] ? fs_reclaim_release+0x90/0xd0 [ 657.701068][ C1] ? mark_lock+0x82/0x1660 [ 657.701072][ C1] tcf_exts_validate+0x138/0x420 [ 657.701075][ C1] ? tcf_exts_destroy+0xc0/0xc0 [ 657.701079][ C1] ? kmem_cache_alloc_trace+0x18e/0x300 [ 657.701082][ C1] ? __nla_parse+0x3d/0x4a [ 657.701085][ C1] route4_change+0x6d8/0x2380 [ 657.701088][ C1] ? route4_delete+0xb70/0xb70 [ 657.701092][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701095][ C1] tc_new_tfilter+0x1398/0x2130 [ 657.701099][ C1] ? route4_delete+0xb70/0xb70 [ 657.701102][ C1] ? tc_del_tfilter+0x15c0/0x15c0 [ 657.701106][ C1] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 657.701110][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 657.701114][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701117][ C1] ? security_capable+0x8f/0xc0 [ 657.701121][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701124][ C1] ? tc_del_tfilter+0x15c0/0x15c0 [ 657.701128][ C1] rtnetlink_rcv_msg+0x80f/0xad0 [ 657.701131][ C1] ? rtnetlink_put_metrics+0x510/0x510 [ 657.701135][ C1] ? lock_acquire+0x1f3/0xaf0 [ 657.701138][ C1] ? netlink_deliver_tap+0x146/0xb70 [ 657.701142][ C1] netlink_rcv_skb+0x15a/0x430 [ 657.701145][ C1] ? rtnetlink_put_metrics+0x510/0x510 [ 657.701149][ C1] ? netlink_ack+0xa10/0xa10 [ 657.701153][ C1] ? __kmalloc_node_track_caller+0x38/0x60 [ 657.701156][ C1] netlink_unicast+0x533/0x7d0 [ 657.701159][ C1] ? netlink_attachskb+0x810/0x810 [ 657.701163][ C1] ? __phys_addr_symbol+0x2c/0x70 [ 657.701166][ C1] ? __check_object_size+0x171/0x3e4 [ 657.701170][ C1] netlink_sendmsg+0x856/0xd90 [ 657.701173][ C1] ? netlink_unicast+0x7d0/0x7d0 [ 657.701177][ C1] ? bpf_lsm_socket_sendmsg+0x5/0x10 [ 657.701180][ C1] ? netlink_unicast+0x7d0/0x7d0 [ 657.701183][ C1] sock_sendmsg+0xcf/0x120 [ 657.701187][ C1] ____sys_sendmsg+0x331/0x810 [ 657.701190][ C1] ? kernel_sendmsg+0x50/0x50 [ 657.701193][ C1] ? do_recvmmsg+0x6d0/0x6d0 [ 657.701197][ C1] ? sock_alloc_file+0x4f/0x190 [ 657.701200][ C1] ? __lock_acquire+0x164a/0x5780 [ 657.701204][ C1] ___sys_sendmsg+0xf3/0x170 [ 657.701207][ C1] ? sendmsg_copy_msghdr+0x160/0x160 [ 657.701211][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 657.701215][ C1] ? fs_reclaim_release+0x90/0xd0 [ 657.701218][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701222][ C1] ? find_held_lock+0x2d/0x110 [ 657.701225][ C1] ? __might_fault+0x11f/0x1d0 [ 657.701229][ C1] ? lock_downgrade+0x830/0x830 [ 657.701232][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701235][ C1] __sys_sendmmsg+0x195/0x480 [ 657.701239][ C1] ? __ia32_sys_sendmsg+0xb0/0xb0 [ 657.701242][ C1] ? find_held_lock+0x2d/0x110 [ 657.701246][ C1] ? __fd_install+0x1b4/0x600 [ 657.701249][ C1] ? alloc_file_pseudo+0x1/0x250 [ 657.701252][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701256][ C1] ? __fd_install+0x1e6/0x600 [ 657.701259][ C1] ? __sys_socket+0x16d/0x200 [ 657.701263][ C1] ? lock_is_held_type+0xbb/0xf0 [ 657.701266][ C1] ? syscall_enter_from_user_mode+0x1d/0x60 [ 657.701270][ C1] __x64_sys_sendmmsg+0x99/0x100 [ 657.701274][ C1] ? syscall_enter_from_user_mode+0x1d/0x60 [ 657.701277][ C1] do_syscall_64+0x2d/0x70 [ 657.701281][ C1] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 657.701284][ C1] RIP: 0033:0x441579 [ 657.701294][ C1] Code: e8 5c ad 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 657.701298][ C1] RSP: 002b:00007ffe0b691e38 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 [ 657.701305][ C1] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441579 [ 657.701310][ C1] RDX: 04924924924926d3 RSI: 0000000020000200 RDI: 0000000000000004 [ 657.701314][ C1] RBP: 00007ffe0b691e40 R08: 0000000100000000 R09: 0000000100000000 [ 657.701319][ C1] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000007950a [ 657.701323][ C1] R13: 0000000000402450 R14: 0000000000000000 R15: 0000000000000000 [ 657.701328][ C1] INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 0.000 msecs [ 657.703529][ T1175] Kernel panic - not syncing: hung_task: blocked tasks [ 658.358443][ T1175] CPU: 0 PID: 1175 Comm: khungtaskd Not tainted 5.9.0-rc6-syzkaller #0 [ 658.366693][ T1175] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 658.376804][ T1175] Call Trace: [ 658.380110][ T1175] dump_stack+0x198/0x1fd [ 658.384548][ T1175] panic+0x382/0x7fb [ 658.388466][ T1175] ? __warn_printk+0xf3/0xf3 [ 658.393107][ T1175] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 658.398735][ T1175] ? preempt_schedule_thunk+0x16/0x18 [ 658.404130][ T1175] ? watchdog.cold+0x5/0x16b [ 658.408724][ T1175] ? watchdog+0xa82/0x1000 [ 658.413150][ T1175] watchdog.cold+0x16/0x16b [ 658.418616][ T1175] ? reset_hung_task_detector+0x30/0x30 [ 658.425290][ T1175] kthread+0x3b5/0x4a0 [ 658.429357][ T1175] ? __kthread_bind_mask+0xc0/0xc0 [ 658.434641][ T1175] ret_from_fork+0x1f/0x30 [ 658.441343][ T1175] Kernel Offset: disabled [ 658.445735][ T1175] Rebooting in 86400 seconds..