[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 64.113442][ T27] kauditd_printk_skb: 7 callbacks suppressed [ 64.113452][ T27] audit: type=1800 audit(1564292808.537:29): pid=9543 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 64.147089][ T27] audit: type=1800 audit(1564292808.537:30): pid=9543 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.1.15' (ECDSA) to the list of known hosts. syzkaller login: [ 191.357430][ T9697] IPVS: ftp: loaded support on port[0] = 21 [ 191.409289][ T9697] chnl_net:caif_netlink_parms(): no params data found [ 191.430218][ T9697] bridge0: port 1(bridge_slave_0) entered blocking state [ 191.437428][ T9697] bridge0: port 1(bridge_slave_0) entered disabled state [ 191.445011][ T9697] device bridge_slave_0 entered promiscuous mode [ 191.452151][ T9697] bridge0: port 2(bridge_slave_1) entered blocking state [ 191.459263][ T9697] bridge0: port 2(bridge_slave_1) entered disabled state [ 191.466708][ T9697] device bridge_slave_1 entered promiscuous mode [ 191.480115][ T9697] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 191.490519][ T9697] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link [ 191.505511][ T9697] team0: Port device team_slave_0 added [ 191.511762][ T9697] team0: Port device team_slave_1 added [ 191.584088][ T9697] device hsr_slave_0 entered promiscuous mode [ 191.652824][ T9697] device hsr_slave_1 entered promiscuous mode [ 191.708166][ T9697] bridge0: port 2(bridge_slave_1) entered blocking state [ 191.715340][ T9697] bridge0: port 2(bridge_slave_1) entered forwarding state [ 191.722657][ T9697] bridge0: port 1(bridge_slave_0) entered blocking state [ 191.729857][ T9697] bridge0: port 1(bridge_slave_0) entered forwarding state [ 191.754439][ T9697] 8021q: adding VLAN 0 to HW filter on device bond0 [ 191.764013][ T3024] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 191.782051][ T3024] bridge0: port 1(bridge_slave_0) entered disabled state [ 191.790060][ T3024] bridge0: port 2(bridge_slave_1) entered disabled state [ 191.798169][ T3024] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 191.807853][ T9697] 8021q: adding VLAN 0 to HW filter on device team0 [ 191.816955][ T3517] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 191.825207][ T3517] bridge0: port 1(bridge_slave_0) entered blocking state [ 191.832333][ T3517] bridge0: port 1(bridge_slave_0) entered forwarding state [ 191.842993][ T12] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready [ 191.851409][ T12] bridge0: port 2(bridge_slave_1) entered blocking state [ 191.858859][ T12] bridge0: port 2(bridge_slave_1) entered forwarding state [ 191.870511][ T22] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 191.878992][ T22] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 191.888697][ T12] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 191.899173][ T22] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready executing program [ 191.909813][ T12] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready [ 191.919305][ T9697] IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready [ 191.934367][ T9697] 8021q: adding VLAN 0 to HW filter on device batadv0 [ 191.961977][ C1] TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. [ 297.122549][ C1] rcu: INFO: rcu_preempt self-detected stall on CPU [ 297.129283][ C1] rcu: 1-...!: (10500 ticks this GP) idle=fc6/1/0x4000000000000002 softirq=9455/9455 fqs=0 [ 297.139421][ C1] (t=10500 jiffies g=9101 q=55) [ 297.144336][ C1] rcu: rcu_preempt kthread starved for 10500 jiffies! g9101 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 [ 297.155576][ C1] rcu: RCU grace-period kthread stack dump: [ 297.161452][ C1] rcu_preempt I29688 10 2 0x80004000 [ 297.167762][ C1] Call Trace: [ 297.171055][ C1] __schedule+0x755/0x15b0 [ 297.175454][ C1] ? __sched_text_start+0x8/0x8 [ 297.180290][ C1] schedule+0xa8/0x270 [ 297.184416][ C1] schedule_timeout+0x486/0xc50 [ 297.189267][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 297.194177][ C1] ? usleep_range+0x170/0x170 [ 297.198826][ C1] ? trace_hardirqs_on+0x67/0x240 [ 297.203856][ C1] ? __kasan_check_read+0x11/0x20 [ 297.208852][ C1] ? __next_timer_interrupt+0x1a0/0x1a0 [ 297.214372][ C1] ? swake_up_one+0x60/0x60 [ 297.218887][ C1] ? trace_hardirqs_on+0x67/0x240 [ 297.223889][ C1] rcu_gp_kthread+0x9b2/0x18c0 [ 297.228626][ C1] ? rcu_barrier+0x310/0x310 [ 297.233184][ C1] ? trace_hardirqs_on+0x67/0x240 [ 297.238179][ C1] ? __kasan_check_read+0x11/0x20 [ 297.243180][ C1] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 297.249391][ C1] ? __kthread_parkme+0x108/0x1c0 [ 297.254395][ C1] ? __kasan_check_read+0x11/0x20 [ 297.259399][ C1] kthread+0x361/0x430 [ 297.263441][ C1] ? rcu_barrier+0x310/0x310 [ 297.268000][ C1] ? kthread_cancel_delayed_work_sync+0x20/0x20 [ 297.274209][ C1] ret_from_fork+0x24/0x30 [ 297.278635][ C1] NMI backtrace for cpu 1 [ 297.282943][ C1] CPU: 1 PID: 9697 Comm: syz-executor455 Not tainted 5.3.0-rc1-next-20190726 #53 [ 297.292018][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 297.302132][ C1] Call Trace: [ 297.305394][ C1] [ 297.308303][ C1] dump_stack+0x172/0x1f0 [ 297.312611][ C1] nmi_cpu_backtrace.cold+0x70/0xb2 [ 297.317786][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 297.324005][ C1] ? lapic_can_unplug_cpu.cold+0x45/0x45 [ 297.329613][ C1] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 297.335582][ C1] arch_trigger_cpumask_backtrace+0x14/0x20 [ 297.341450][ C1] rcu_dump_cpu_stacks+0x183/0x1cf [ 297.346541][ C1] rcu_sched_clock_irq.cold+0x4dd/0xc13 [ 297.352066][ C1] ? raise_softirq+0x138/0x340 [ 297.356809][ C1] update_process_times+0x32/0x80 [ 297.361808][ C1] tick_sched_handle+0xa2/0x190 [ 297.366636][ C1] tick_sched_timer+0x53/0x140 [ 297.371377][ C1] __hrtimer_run_queues+0x364/0xe40 [ 297.376554][ C1] ? tick_sched_do_timer+0x1b0/0x1b0 [ 297.381816][ C1] ? hrtimer_start_range_ns+0xcb0/0xcb0 [ 297.387336][ C1] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 297.393031][ C1] ? ktime_get_update_offsets_now+0x2d3/0x440 [ 297.399073][ C1] hrtimer_interrupt+0x314/0x770 [ 297.403993][ C1] smp_apic_timer_interrupt+0x160/0x610 [ 297.409517][ C1] apic_timer_interrupt+0xf/0x20 [ 297.414432][ C1] RIP: 0010:__kasan_check_read+0x8/0x20 [ 297.419955][ C1] Code: 8b 4d d0 e9 27 ee ff ff 48 8b 73 58 89 c2 48 c7 c7 c8 a9 89 88 f7 da e8 7a 48 af ff e9 da ee ff ff 90 55 89 f6 31 d2 48 89 e5 <48> 8b 4d 08 e8 cf 26 00 00 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 [ 297.440399][ C1] RSP: 0018:ffff8880ae909200 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 297.448782][ C1] RAX: 0000000000000000 RBX: ffff888093832d08 RCX: ffffffff8159a3d7 [ 297.456728][ C1] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888093832d08 [ 297.464675][ C1] RBP: ffff8880ae909200 R08: 1ffff110127065a1 R09: ffffed10127065a2 [ 297.472623][ C1] R10: ffffed10127065a1 R11: ffff888093832d0b R12: 0000000000000001 [ 297.480570][ C1] R13: 0000000000000003 R14: ffffed10127065a1 R15: 0000000000000001 [ 297.488524][ C1] ? apic_timer_interrupt+0xa/0x20 [ 297.493612][ C1] ? native_queued_spin_lock_slowpath+0xb7/0x9f0 [ 297.499915][ C1] native_queued_spin_lock_slowpath+0xb7/0x9f0 [ 297.506044][ C1] ? __pv_queued_spin_lock_slowpath+0xd10/0xd10 [ 297.512260][ C1] ? mark_held_locks+0xf0/0xf0 [ 297.517002][ C1] do_raw_spin_lock+0x20e/0x2e0 [ 297.521828][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 297.526740][ C1] ? lock_acquire+0x190/0x410 [ 297.531434][ C1] ? release_sock+0x20/0x1c0 [ 297.536000][ C1] ? __kasan_check_read+0x11/0x20 [ 297.541000][ C1] _raw_spin_lock_bh+0x3b/0x50 [ 297.545750][ C1] ? release_sock+0x20/0x1c0 [ 297.550313][ C1] release_sock+0x20/0x1c0 [ 297.554744][ C1] wait_on_pending_writer+0x20f/0x420 [ 297.560107][ C1] ? ip6_rcv_finish+0x1de/0x2f0 [ 297.564933][ C1] ? tls_init+0x560/0x560 [ 297.569259][ C1] ? process_backlog+0x206/0x750 [ 297.574172][ C1] ? net_rx_action+0x508/0x10c0 [ 297.578998][ C1] ? __do_softirq+0x262/0x98c [ 297.583651][ C1] ? prepare_to_wait_exclusive+0x320/0x320 [ 297.589462][ C1] ? inet_release+0xed/0x200 [ 297.594042][ C1] ? inet6_release+0x53/0x80 [ 297.598654][ C1] ? __sock_release+0xce/0x280 [ 297.603397][ C1] ? sock_close+0x1e/0x30 [ 297.607702][ C1] ? __fput+0x2ff/0x890 [ 297.611830][ C1] ? ____fput+0x16/0x20 [ 297.615973][ C1] ? task_work_run+0x145/0x1c0 [ 297.620712][ C1] ? exit_to_usermode_loop+0x316/0x380 [ 297.626147][ C1] tls_sk_proto_cleanup+0x2c5/0x3e0 [ 297.631321][ C1] ? wait_on_pending_writer+0x420/0x420 [ 297.636844][ C1] tls_sk_proto_unhash+0x90/0x3f0 [ 297.641878][ C1] tcp_set_state+0x5b9/0x7d0 [ 297.646449][ C1] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 297.652683][ C1] ? __sk_mem_reduce_allocated+0x1b0/0x560 [ 297.658464][ C1] ? tcp_alloc_md5sig_pool+0x4a0/0x4a0 [ 297.663901][ C1] ? __sk_mem_reclaim+0x55/0x70 [ 297.668728][ C1] ? tcp_write_queue_purge+0x5d8/0x1310 [ 297.674290][ C1] ? inet6_sk_rx_dst_set+0x244/0x6f0 [ 297.679565][ C1] tcp_done+0xe2/0x320 [ 297.683610][ C1] tcp_reset+0x132/0x500 [ 297.687829][ C1] tcp_validate_incoming+0xa2d/0x1660 [ 297.693179][ C1] tcp_rcv_established+0x6b5/0x1e70 [ 297.698354][ C1] ? mark_held_locks+0xf0/0xf0 [ 297.703131][ C1] ? sk_filter_trim_cap+0x45f/0xb30 [ 297.708902][ C1] ? tcp_data_queue+0x4860/0x4860 [ 297.713907][ C1] ? do_raw_spin_lock+0x12a/0x2e0 [ 297.719516][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 297.724430][ C1] ? lock_acquire+0x190/0x410 [ 297.729089][ C1] tcp_v6_do_rcv+0x41e/0x12c0 [ 297.733744][ C1] tcp_v6_rcv+0x31f1/0x3500 [ 297.738232][ C1] ? tcp_v6_syn_recv_sock+0x2290/0x2290 [ 297.743804][ C1] ? nf_confirm+0x360/0x4d0 [ 297.748283][ C1] ? mark_held_locks+0xf0/0xf0 [ 297.753024][ C1] ip6_protocol_deliver_rcu+0x2fe/0x1660 [ 297.758639][ C1] ip6_input_finish+0x84/0x170 [ 297.763378][ C1] ip6_input+0xe4/0x3f0 [ 297.767510][ C1] ? ip6_input_finish+0x170/0x170 [ 297.772509][ C1] ? __kasan_check_read+0x11/0x20 [ 297.777516][ C1] ? ip6_protocol_deliver_rcu+0x1660/0x1660 [ 297.783381][ C1] ? lock_downgrade+0x920/0x920 [ 297.788211][ C1] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 297.794424][ C1] ip6_rcv_finish+0x1de/0x2f0 [ 297.799080][ C1] ipv6_rcv+0x10e/0x420 [ 297.803210][ C1] ? ip6_rcv_core.isra.0+0x1bb0/0x1bb0 [ 297.808642][ C1] ? lock_downgrade+0x920/0x920 [ 297.813466][ C1] ? lock_downgrade+0x920/0x920 [ 297.818289][ C1] ? ip6_rcv_finish_core.isra.0+0x560/0x560 [ 297.824159][ C1] ? trace_hardirqs_off+0x62/0x240 [ 297.829255][ C1] ? ip6_rcv_core.isra.0+0x1bb0/0x1bb0 [ 297.834689][ C1] __netif_receive_skb_one_core+0x113/0x1a0 [ 297.840558][ C1] ? __netif_receive_skb_core+0x3060/0x3060 [ 297.846427][ C1] ? lock_acquire+0x190/0x410 [ 297.851080][ C1] ? process_backlog+0x195/0x750 [ 297.855991][ C1] __netif_receive_skb+0x2c/0x1d0 [ 297.860989][ C1] process_backlog+0x206/0x750 [ 297.865730][ C1] ? lock_acquire+0x190/0x410 [ 297.870394][ C1] ? clockevents_program_event+0x15a/0x370 [ 297.877693][ C1] net_rx_action+0x508/0x10c0 [ 297.882356][ C1] ? napi_complete_done+0x4b0/0x4b0 [ 297.887528][ C1] ? sched_clock+0x2e/0x50 [ 297.891918][ C1] ? kvm_clock_read+0x18/0x30 [ 297.896574][ C1] ? inet_csk_listen_stop+0x1bc/0x850 [ 297.901924][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 297.908146][ C1] __do_softirq+0x262/0x98c [ 297.912628][ C1] ? inet_csk_listen_stop+0x1bc/0x850 [ 297.917976][ C1] do_softirq_own_stack+0x2a/0x40 [ 297.922972][ C1] [ 297.925888][ C1] do_softirq.part.0+0x11a/0x170 [ 297.930799][ C1] __local_bh_enable_ip+0x211/0x270 [ 297.935971][ C1] inet_csk_listen_stop+0x1e0/0x850 [ 297.941147][ C1] tcp_close+0xd5b/0x10e0 [ 297.945454][ C1] ? ip_mc_drop_socket+0x211/0x270 [ 297.950539][ C1] ? down_write+0xdf/0x150 [ 297.954939][ C1] inet_release+0xed/0x200 [ 297.959334][ C1] inet6_release+0x53/0x80 [ 297.963727][ C1] __sock_release+0xce/0x280 [ 297.968292][ C1] sock_close+0x1e/0x30 [ 297.972429][ C1] __fput+0x2ff/0x890 [ 297.976390][ C1] ? __sock_release+0x280/0x280 [ 297.981223][ C1] ____fput+0x16/0x20 [ 297.985181][ C1] task_work_run+0x145/0x1c0 [ 297.989751][ C1] exit_to_usermode_loop+0x316/0x380 [ 297.995010][ C1] do_syscall_64+0x65f/0x760 [ 297.999576][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 298.005443][ C1] RIP: 0033:0x406581 [ 298.009334][ C1] Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 24 1a 00 00 c3 48 83 ec 08 e8 6a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 b3 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 [ 298.028927][ C1] RSP: 002b:00007ffca01be890 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 [ 298.037312][ C1] RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000406581 [ 298.045258][ C1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 [ 298.053204][ C1] RBP: 00000000006dcc20 R08: 0000000000000140 R09: 0000000000000140 [ 298.061153][ C1] R10: 00007ffca01be8c0 R11: 0000000000000293 R12: 00007ffca01be8f0 [ 298.069100][ C1] R13: 00000000006dcc2c R14: 000000000000002d R15: 0000000000000007 [ 301.442596][ T3024] rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-... } 10904 jiffies s: 105 root: 0x2/. [ 301.454458][ T3024] rcu: blocking rcu_node structures: [ 301.459722][ T3024] Task dump for CPU 1: [ 301.464130][ T3024] syz-executor455 R running task 24184 9697 9696 0x8000000a [ 301.472017][ T3024] Call Trace: [ 301.475785][ T3024] ? __kasan_check_read+0x11/0x20 [ 301.480796][ T3024] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 301.487224][ T3024] ? lock_downgrade+0x920/0x920 [ 301.492055][ T3024] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 301.498740][ T3024] ? __this_cpu_preempt_check+0x3a/0x210 [ 301.504493][ T3024] ? inet_csk_listen_stop+0x1bc/0x850 [ 301.509857][ T3024] ? ksoftirqd_running+0x16/0x70 [ 301.515228][ T3024] ? inet_csk_listen_stop+0x1bc/0x850 [ 301.520578][ T3024] ? do_softirq.part.0+0x11a/0x170 [ 301.525818][ T3024] ? __local_bh_enable_ip+0x211/0x270 [ 301.531171][ T3024] ? inet_csk_listen_stop+0x1e0/0x850 [ 301.536961][ T3024] ? tcp_close+0xd5b/0x10e0 [ 301.541446][ T3024] ? ip_mc_drop_socket+0x211/0x270 [ 301.546677][ T3024] ? down_write+0xdf/0x150 [ 301.551074][ T3024] ? inet_release+0xed/0x200 [ 301.556070][ T3024] ? inet6_release+0x53/0x80 [ 301.560645][ T3024] ? __sock_release+0xce/0x280 [ 301.565516][ T3024] ? sock_close+0x1e/0x30 [ 301.569824][ T3024] ? __fput+0x2ff/0x890 [ 301.574394][ T3024] ? __sock_release+0x280/0x280 [ 301.579228][ T3024] ? ____fput+0x16/0x20 [ 301.583515][ T3024] ? task_work_run+0x145/0x1c0 [ 301.588268][ T3024] ? exit_to_usermode_loop+0x316/0x380 [ 301.594158][ T3024] ? do_syscall_64+0x65f/0x760 [ 301.598904][ T3024] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe