[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Started OpenBSD Secure Shell server. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.10' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 489.491466][ T6857] IPVS: ftp: loaded support on port[0] = 21 [ 489.535209][ T6878] netlink: 8 bytes leftover after parsing attributes in process `syz-executor427'. [ 489.545960][ T6878] netlink: 5212 bytes leftover after parsing attributes in process `syz-executor427'. [ 489.557885][ T6878] netlink: 8 bytes leftover after parsing attributes in process `syz-executor427'. [ 489.567370][ T6878] netlink: 5212 bytes leftover after parsing attributes in process `syz-executor427'. [ 657.182953][ T1172] INFO: task kworker/0:2:2472 blocked for more than 143 seconds. [ 657.182975][ T1172] Not tainted 5.9.0-rc6-syzkaller #0 [ 657.182981][ T1172] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 657.182998][ T1172] task:kworker/0:2 state:D stack:27272 pid: 2472 ppid: 2 flags:0x00004000 [ 657.183139][ T1172] Workqueue: ipv6_addrconf addrconf_verify_work [ 657.228645][ T1172] Call Trace: [ 657.231972][ T1172] __schedule+0xec9/0x2280 [ 657.237707][ T1172] ? io_schedule_timeout+0x140/0x140 [ 657.243927][ T1172] ? lockdep_hardirqs_on_prepare+0x354/0x530 [ 657.249945][ T1172] ? _raw_spin_unlock_irq+0x1f/0x80 [ 657.256598][ T1172] ? lockdep_hardirqs_on+0x53/0x100 [ 657.261813][ T1172] schedule+0xd0/0x2a0 [ 657.267259][ T1172] schedule_preempt_disabled+0xf/0x20 [ 657.272641][ T1172] __mutex_lock+0x3e2/0x10e0 [ 657.279636][ T1172] ? addrconf_verify_work+0xa/0x20 [ 657.285605][ T1172] ? mutex_lock_io_nested+0xf60/0xf60 [ 657.291001][ T1172] ? lock_release+0x8f0/0x8f0 [ 657.296922][ T1172] ? lock_downgrade+0x830/0x830 [ 657.301785][ T1172] ? _raw_spin_unlock_irq+0x1f/0x80 [ 657.308241][ T1172] ? lock_is_held_type+0xbb/0xf0 [ 657.313986][ T1172] addrconf_verify_work+0xa/0x20 [ 657.318932][ T1172] process_one_work+0x94c/0x1670 [ 657.325175][ T1172] ? lock_release+0x8f0/0x8f0 [ 657.329877][ T1172] ? pwq_dec_nr_in_flight+0x320/0x320 [ 657.336458][ T1172] ? rwlock_bug.part.0+0x90/0x90 [ 657.341408][ T1172] ? lockdep_hardirqs_off+0x96/0xd0 [ 657.347869][ T1172] worker_thread+0x64c/0x1120 [ 657.352567][ T1172] ? __kthread_parkme+0x13f/0x1e0 [ 657.358859][ T1172] ? process_one_work+0x1670/0x1670 [ 657.364897][ T1172] kthread+0x3b5/0x4a0 [ 657.368977][ T1172] ? __kthread_bind_mask+0xc0/0xc0 [ 657.375333][ T1172] ret_from_fork+0x1f/0x30 [ 657.379880][ T1172] [ 657.379880][ T1172] Showing all locks held in the system: [ 657.388894][ T1172] 1 lock held by khungtaskd/1172: [ 657.394753][ T1172] #0: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [ 657.407372][ T1172] 3 locks held by kworker/0:2/2472: [ 657.412591][ T1172] #0: ffff888214deb138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 [ 657.426020][ T1172] #1: ffffc9000898fda8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 [ 657.437034][ T1172] #2: ffffffff8b14d548 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 [ 657.447342][ T1172] 1 lock held by in:imklog/6548: [ 657.452275][ T1172] #0: ffff8880968ceaf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 [ 657.462932][ T1172] 2 locks held by syz-executor427/6878: [ 657.468503][ T1172] [ 657.470823][ T1172] ============================================= [ 657.470823][ T1172] [ 657.481059][ T1172] NMI backtrace for cpu 1 [ 657.485494][ T1172] CPU: 1 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc6-syzkaller #0 [ 657.493728][ T1172] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 657.503778][ T1172] Call Trace: [ 657.507151][ T1172] dump_stack+0x198/0x1fd [ 657.511486][ T1172] nmi_cpu_backtrace.cold+0x70/0xb1 [ 657.516685][ T1172] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 657.522313][ T1172] nmi_trigger_cpumask_backtrace+0x1b3/0x223 [ 657.528290][ T1172] watchdog+0xd7d/0x1000 [ 657.532531][ T1172] ? reset_hung_task_detector+0x30/0x30 [ 657.538074][ T1172] kthread+0x3b5/0x4a0 [ 657.542310][ T1172] ? __kthread_bind_mask+0xc0/0xc0 [ 657.547420][ T1172] ret_from_fork+0x1f/0x30 [ 657.552036][ T1172] Sending NMI from CPU 1 to CPUs 0: [ 657.558770][ C0] NMI backtrace for cpu 0 [ 657.558776][ C0] CPU: 0 PID: 6878 Comm: syz-executor427 Not tainted 5.9.0-rc6-syzkaller #0 [ 657.558783][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 657.558787][ C0] RIP: 0010:__lock_acquire+0x9c5/0x5780 [ 657.558799][ C0] Code: b8 00 00 00 00 00 fc ff df 49 8d 7d 21 48 89 fa 48 c1 ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 93 45 00 00 <49> 8d 7c 24 21 45 0f b6 6d 21 48 b8 00 00 00 00 00 fc ff df 48 89 [ 657.558803][ C0] RSP: 0018:ffffc900057069a0 EFLAGS: 00000046 [ 657.558812][ C0] RAX: 0000000000000000 RBX: 8260a2b76483d3d2 RCX: ffffffff815baa30 [ 657.558817][ C0] RDX: 0000000000000001 RSI: ffff888095f7cba8 RDI: ffff888095f7cbc9 [ 657.558823][ C0] RBP: ffff888095f7c2c0 R08: 0000000000000000 R09: ffffffff8d0c0a9f [ 657.558828][ C0] R10: 0000000000000001 R11: 0000000000000000 R12: ffff888095f7cbd0 [ 657.558834][ C0] R13: ffff888095f7cba8 R14: 0000000000000000 R15: 0000000000000000 [ 657.558840][ C0] FS: 0000000000aef880(0000) GS:ffff8880ae400000(0000) knlGS:0000000000000000 [ 657.558844][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 657.558850][ C0] CR2: 00007fed4dbc4018 CR3: 00000000a178b000 CR4: 00000000001506f0 [ 657.558855][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 657.558861][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 657.558864][ C0] Call Trace: [ 657.558868][ C0] ? _raw_spin_unlock_irq+0x55/0x80 [ 657.558872][ C0] ? finish_task_switch+0x150/0x790 [ 657.558876][ C0] ? finish_task_switch+0x122/0x790 [ 657.558880][ C0] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 657.558884][ C0] ? __schedule+0xed1/0x2280 [ 657.558888][ C0] lock_acquire+0x1f3/0xaf0 [ 657.558892][ C0] ? tcf_idr_check_alloc+0x78/0x3b0 [ 657.558895][ C0] ? lock_release+0x8f0/0x8f0 [ 657.558899][ C0] ? preempt_schedule_thunk+0x16/0x18 [ 657.558903][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.558907][ C0] __mutex_lock+0x134/0x10e0 [ 657.558911][ C0] ? tcf_idr_check_alloc+0x78/0x3b0 [ 657.558915][ C0] ? tcf_idr_check_alloc+0x78/0x3b0 [ 657.558919][ C0] ? mutex_lock_io_nested+0xf60/0xf60 [ 657.558923][ C0] ? __mutex_unlock_slowpath+0xe2/0x610 [ 657.558927][ C0] ? wait_for_completion+0x260/0x260 [ 657.558931][ C0] tcf_idr_check_alloc+0x78/0x3b0 [ 657.558935][ C0] tcf_police_init+0x347/0x13a0 [ 657.558939][ C0] ? tcf_police_cleanup+0x60/0x60 [ 657.558943][ C0] ? find_held_lock+0x2d/0x110 [ 657.558947][ C0] ? tc_lookup_action_n+0xcd/0xf0 [ 657.558951][ C0] tcf_action_init_1+0x1a3/0x990 [ 657.558955][ C0] ? tcf_action_dump_old+0x80/0x80 [ 657.558958][ C0] ? lock_acquire+0x1f3/0xaf0 [ 657.558962][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.558966][ C0] ? find_held_lock+0x2d/0x110 [ 657.558970][ C0] ? fs_reclaim_release+0x90/0xd0 [ 657.558974][ C0] ? mark_lock+0x82/0x1660 [ 657.558978][ C0] tcf_exts_validate+0x138/0x420 [ 657.558981][ C0] ? tcf_exts_destroy+0xc0/0xc0 [ 657.558985][ C0] ? kmem_cache_alloc_trace+0x18e/0x300 [ 657.558989][ C0] ? __nla_parse+0x3d/0x4a [ 657.558993][ C0] rsvp_change+0x291/0x2990 [ 657.558997][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559001][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559004][ C0] ? find_held_lock+0x2d/0x110 [ 657.559008][ C0] ? tc_new_tfilter+0x1be4/0x2130 [ 657.559012][ C0] ? tcf_bind_filter.isra.0+0x3c0/0x3c0 [ 657.559016][ C0] ? lock_downgrade+0x830/0x830 [ 657.559020][ C0] ? blackhole_dequeue+0x10/0x10 [ 657.559024][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559028][ C0] tc_new_tfilter+0x1398/0x2130 [ 657.559032][ C0] ? tcf_bind_filter.isra.0+0x3c0/0x3c0 [ 657.559036][ C0] ? tc_del_tfilter+0x15c0/0x15c0 [ 657.559040][ C0] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 657.559044][ C0] ? is_bpf_text_address+0xcb/0x160 [ 657.559048][ C0] ? kernel_text_address+0xbd/0xf0 [ 657.559052][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559056][ C0] ? security_capable+0x8f/0xc0 [ 657.559060][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559064][ C0] ? tc_del_tfilter+0x15c0/0x15c0 [ 657.559068][ C0] rtnetlink_rcv_msg+0x80f/0xad0 [ 657.559079][ C0] ? rtnetlink_put_metrics+0x510/0x510 [ 657.559083][ C0] ? lock_acquire+0x1f3/0xaf0 [ 657.559087][ C0] ? netlink_deliver_tap+0x146/0xb70 [ 657.559091][ C0] netlink_rcv_skb+0x15a/0x430 [ 657.559095][ C0] ? rtnetlink_put_metrics+0x510/0x510 [ 657.559099][ C0] ? netlink_ack+0xa10/0xa10 [ 657.559103][ C0] netlink_unicast+0x533/0x7d0 [ 657.559107][ C0] ? netlink_attachskb+0x810/0x810 [ 657.559111][ C0] ? __phys_addr_symbol+0x2c/0x70 [ 657.559115][ C0] ? __check_object_size+0x171/0x3e4 [ 657.559119][ C0] netlink_sendmsg+0x856/0xd90 [ 657.559122][ C0] ? netlink_unicast+0x7d0/0x7d0 [ 657.559127][ C0] ? bpf_lsm_socket_sendmsg+0x5/0x10 [ 657.559130][ C0] ? netlink_unicast+0x7d0/0x7d0 [ 657.559134][ C0] sock_sendmsg+0xcf/0x120 [ 657.559138][ C0] ____sys_sendmsg+0x331/0x810 [ 657.559142][ C0] ? kernel_sendmsg+0x50/0x50 [ 657.559145][ C0] ? do_recvmmsg+0x6d0/0x6d0 [ 657.559149][ C0] ? sock_alloc_file+0x4f/0x190 [ 657.559153][ C0] ? __lock_acquire+0x164a/0x5780 [ 657.559157][ C0] ___sys_sendmsg+0xf3/0x170 [ 657.559161][ C0] ? sendmsg_copy_msghdr+0x160/0x160 [ 657.559165][ C0] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 657.559169][ C0] ? fs_reclaim_release+0x90/0xd0 [ 657.559173][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559177][ C0] ? find_held_lock+0x2d/0x110 [ 657.559181][ C0] ? __might_fault+0x11f/0x1d0 [ 657.559184][ C0] ? lock_downgrade+0x830/0x830 [ 657.559188][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559192][ C0] __sys_sendmmsg+0x195/0x480 [ 657.559196][ C0] ? __ia32_sys_sendmsg+0xb0/0xb0 [ 657.559200][ C0] ? find_held_lock+0x2d/0x110 [ 657.559203][ C0] ? __fd_install+0x1b4/0x600 [ 657.559207][ C0] ? alloc_file_pseudo+0x1/0x250 [ 657.559211][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559215][ C0] ? __fd_install+0x1e6/0x600 [ 657.559219][ C0] ? __sys_socket+0x16d/0x200 [ 657.559223][ C0] ? lock_is_held_type+0xbb/0xf0 [ 657.559227][ C0] ? syscall_enter_from_user_mode+0x1d/0x60 [ 657.559231][ C0] __x64_sys_sendmmsg+0x99/0x100 [ 657.559235][ C0] ? syscall_enter_from_user_mode+0x1d/0x60 [ 657.559239][ C0] do_syscall_64+0x2d/0x70 [ 657.559243][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 657.559247][ C0] RIP: 0033:0x441599 [ 657.559258][ C0] 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 [ 657.559262][ C0] RSP: 002b:00007ffec0eca238 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 [ 657.559272][ C0] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441599 [ 657.559277][ C0] RDX: 04924924924926d3 RSI: 0000000020000200 RDI: 0000000000000004 [ 657.559282][ C0] RBP: 00007ffec0eca240 R08: 0000000120080522 R09: 0000000120080522 [ 657.559288][ C0] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004a3bb0 [ 657.559294][ C0] R13: 0000000000402470 R14: 0000000000000000 R15: 0000000000000000 [ 657.559301][ C0] INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 0.000 msecs [ 657.565899][ T1172] Kernel panic - not syncing: hung_task: blocked tasks [ 658.258098][ T1172] CPU: 1 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc6-syzkaller #0 [ 658.266323][ T1172] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 658.276459][ T1172] Call Trace: [ 658.279759][ T1172] dump_stack+0x198/0x1fd [ 658.284089][ T1172] panic+0x382/0x7fb [ 658.287993][ T1172] ? __warn_printk+0xf3/0xf3 [ 658.292589][ T1172] ? lapic_can_unplug_cpu.cold+0x38/0x38 [ 658.298215][ T1172] ? preempt_schedule_thunk+0x16/0x18 [ 658.303586][ T1172] ? watchdog.cold+0x5/0x16b [ 658.308168][ T1172] ? watchdog+0xa82/0x1000 [ 658.312580][ T1172] watchdog.cold+0x16/0x16b [ 658.317083][ T1172] ? reset_hung_task_detector+0x30/0x30 [ 658.322628][ T1172] kthread+0x3b5/0x4a0 [ 658.326711][ T1172] ? __kthread_bind_mask+0xc0/0xc0 [ 658.331827][ T1172] ret_from_fork+0x1f/0x30 [ 658.337431][ T1172] Kernel Offset: disabled [ 658.341751][ T1172] Rebooting in 86400 seconds..