[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.851557] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 25.334547] random: sshd: uninitialized urandom read (32 bytes read) [ 25.764927] random: sshd: uninitialized urandom read (32 bytes read) [ 26.289257] random: sshd: uninitialized urandom read (32 bytes read) [ 26.459219] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.198' (ECDSA) to the list of known hosts. [ 31.949734] random: sshd: uninitialized urandom read (32 bytes read) [ 32.050938] IPVS: ftp: loaded support on port[0] = 21 [ 32.176862] bridge0: port 1(bridge_slave_0) entered blocking state [ 32.183314] bridge0: port 1(bridge_slave_0) entered disabled state [ 32.190638] device bridge_slave_0 entered promiscuous mode [ 32.206982] bridge0: port 2(bridge_slave_1) entered blocking state [ 32.213344] bridge0: port 2(bridge_slave_1) entered disabled state [ 32.220308] device bridge_slave_1 entered promiscuous mode [ 32.235488] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 32.251966] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 32.291716] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 32.309011] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 32.368583] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 32.376108] team0: Port device team_slave_0 added [ 32.389847] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 32.396896] team0: Port device team_slave_1 added [ 32.411398] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 32.427992] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 32.445803] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 32.461750] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 32.578858] bridge0: port 2(bridge_slave_1) entered blocking state [ 32.585305] bridge0: port 2(bridge_slave_1) entered forwarding state [ 32.592060] bridge0: port 1(bridge_slave_0) entered blocking state [ 32.598418] bridge0: port 1(bridge_slave_0) entered forwarding state RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument [ 33.008303] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 33.014520] 8021q: adding VLAN 0 to HW filter on device bond0 [ 33.056186] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 33.098189] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 33.105692] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 33.141563] 8021q: adding VLAN 0 to HW filter on device team0 executing program [ 33.417351] BUG: please report to dccp@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:425/tfrc_rx_hist_sample_rtt() [ 33.431275] CPU: 1 PID: 4688 Comm: syz-executor250 Not tainted 4.18.0-rc8+ #182 [ 33.438734] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.448220] Call Trace: [ 33.450901] [ 33.453039] dump_stack+0x1c9/0x2b4 [ 33.456657] ? dump_stack_print_info.cold.2+0x52/0x52 [ 33.461841] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 33.467361] ? tfrc_rx_handle_loss+0x67c/0x1eb0 [ 33.472248] ? rcu_is_watching+0x8c/0x150 [ 33.476381] tfrc_rx_hist_sample_rtt.cold.3+0x54/0x5c [ 33.481653] ccid3_hc_rx_packet_recv+0x5c4/0xeb0 [ 33.486399] ? dccp_parse_options+0x493/0x11f0 [ 33.490973] ? ccid3_hc_tx_send_packet+0x880/0x880 [ 33.495958] dccp_deliver_input_to_ccids+0xf0/0x280 [ 33.500978] dccp_rcv_established+0x87/0xb0 [ 33.505287] dccp_v4_do_rcv+0x153/0x180 [ 33.509268] __sk_receive_skb+0x3c0/0xd90 [ 33.513398] ? __inet_lookup_established+0x462/0x690 [ 33.518479] ? sk_free+0x50/0x50 [ 33.521825] ? inet_lhash2_lookup+0x6e0/0x6e0 [ 33.526298] ? reqsk_fastopen_remove+0x680/0x680 [ 33.531035] ? lock_downgrade+0x8f0/0x8f0 [ 33.535180] ? dccp_invalid_packet+0x64/0x890 [ 33.539655] dccp_v4_rcv+0x10f9/0x1f58 [ 33.543557] ? dccp_v4_err+0x1860/0x1860 [ 33.547607] ? __lock_is_held+0xb5/0x140 [ 33.551662] ip_local_deliver_finish+0x2eb/0xda0 [ 33.556409] ? inet_add_protocol.cold.0+0x21/0x21 [ 33.561355] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 33.566361] ? nf_hook_slow+0x11e/0x1c0 [ 33.570319] ip_local_deliver+0x1e9/0x750 [ 33.574461] ? nf_conntrack_update+0xc80/0xc80 [ 33.579375] ? ip_call_ra_chain+0x730/0x730 [ 33.583678] ? inet_add_protocol.cold.0+0x21/0x21 [ 33.588500] ? graph_lock+0x170/0x170 [ 33.592552] ? graph_lock+0x170/0x170 [ 33.596362] ? ipv6_rcv+0x2060/0x2060 [ 33.600219] ip_rcv_finish+0x823/0x2220 [ 33.604186] ? ip_local_deliver_finish+0xda0/0xda0 [ 33.609104] ? lock_downgrade+0x8f0/0x8f0 [ 33.613311] ? kasan_check_read+0x11/0x20 [ 33.617729] ? rcu_is_watching+0x8c/0x150 [ 33.621862] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 33.626254] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 33.631280] ? nf_hook_slow+0x11e/0x1c0 [ 33.635260] ip_rcv+0xa18/0x1284 [ 33.638642] ? ip_local_deliver+0x750/0x750 [ 33.642947] ? ip_local_deliver_finish+0xda0/0xda0 [ 33.647881] ? __lock_is_held+0xb5/0x140 [ 33.651927] ? ip_local_deliver+0x750/0x750 [ 33.656231] __netif_receive_skb_core+0x23d0/0x35b0 [ 33.661228] ? nf_ingress+0xa30/0xa30 [ 33.665012] ? __lock_acquire+0x7fc/0x5020 [ 33.669227] ? trace_hardirqs_on+0x10/0x10 [ 33.673700] ? trace_hardirqs_on+0x10/0x10 [ 33.677943] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 33.683937] ? secondary_startup_64+0xa5/0xb0 [ 33.688537] ? trace_hardirqs_on+0x10/0x10 [ 33.692756] ? unwind_next_frame.part.7+0x1ae/0x9e0 [ 33.697847] ? unwind_dump+0x190/0x190 [ 33.701718] ? unwind_dump+0x190/0x190 [ 33.705588] ? secondary_startup_64+0xa5/0xb0 [ 33.710069] ? graph_lock+0x170/0x170 [ 33.713880] ? unwind_next_frame+0x3e/0x50 [ 33.718155] ? __save_stack_trace+0x7d/0xf0 [ 33.722463] ? find_held_lock+0x36/0x1c0 [ 33.726584] ? print_usage_bug+0xc0/0xc0 [ 33.730720] ? lock_acquire+0x1e4/0x540 [ 33.734752] ? process_backlog+0x1a6/0x760 [ 33.738993] ? kasan_check_read+0x11/0x20 [ 33.743129] ? rcu_is_watching+0x8c/0x150 [ 33.747267] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 33.751662] __netif_receive_skb+0x2c/0x1e0 [ 33.755976] process_backlog+0x219/0x760 [ 33.760099] net_rx_action+0x7da/0x1980 [ 33.764067] ? napi_complete_done+0x6c0/0x6c0 [ 33.768553] ? rcu_read_lock_sched_held+0x108/0x120 [ 33.773655] ? rcu_process_callbacks+0x1251/0x1850 [ 33.778586] ? call_rcu_sched+0x20/0x20 [ 33.782552] ? enqueue_hrtimer+0x18e/0x540 [ 33.786840] ? rcu_is_watching+0x8c/0x150 [ 33.790975] ? find_held_lock+0x36/0x1c0 [ 33.795019] ? lock_downgrade+0x8f0/0x8f0 [ 33.799151] ? kasan_check_read+0x11/0x20 [ 33.803277] ? rcu_is_watching+0x8c/0x150 [ 33.807405] ? rcu_pm_notify+0xc0/0xc0 [ 33.811345] ? print_usage_bug+0xc0/0xc0 [ 33.815394] ? __do_softirq+0x780/0xb17 [ 33.819355] ? graph_lock+0x170/0x170 [ 33.823141] ? scheduler_ipi+0x1a8/0xa50 [ 33.827188] ? migration_cpu_stop+0x470/0x470 [ 33.831673] ? __lock_is_held+0xb5/0x140 [ 33.835873] __do_softirq+0x2e8/0xb17 [ 33.839725] ? __irqentry_text_end+0x1f97a8/0x1f97a8 [ 33.844828] ? smp_reschedule_interrupt+0xf5/0x670 [ 33.849754] ? smp_thermal_interrupt+0x820/0x820 [ 33.854708] ? _raw_spin_unlock+0x22/0x30 [ 33.858840] ? handle_edge_irq+0x330/0x870 [ 33.863197] ? task_prio+0x50/0x50 [ 33.866858] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.871685] do_softirq_own_stack+0x2a/0x40 [ 33.875980] [ 33.878196] do_softirq.part.17+0x155/0x1a0 [ 33.882500] ? ip_finish_output2+0xa87/0x1860 [ 33.886973] __local_bh_enable_ip+0x1ec/0x230 [ 33.891455] ip_finish_output2+0xaba/0x1860 [ 33.895888] ? ip_copy_metadata+0xb30/0xb30 [ 33.900319] ? graph_lock+0x170/0x170 [ 33.904105] ? nf_ct_deliver_cached_events+0x558/0x7d0 [ 33.909525] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 33.915062] ? ipv4_mtu+0x37d/0x590 [ 33.918698] ? __lock_is_held+0xb5/0x140 [ 33.922785] ip_finish_output+0x841/0xfa0 [ 33.927034] ? ip_finish_output+0x841/0xfa0 [ 33.931466] ? ip_fragment.constprop.49+0x240/0x240 [ 33.936468] ? kasan_check_read+0x11/0x20 [ 33.940619] ? rcu_is_watching+0x8c/0x150 [ 33.944746] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 33.949137] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 33.954155] ? nf_hook_slow+0x11e/0x1c0 [ 33.958111] ip_output+0x223/0x880 [ 33.961631] ? __ip_local_out+0x5e3/0xb50 [ 33.965758] ? ip_mc_output+0x15d0/0x15d0 [ 33.970037] ? ip_fragment.constprop.49+0x240/0x240 [ 33.975075] ? __lock_is_held+0xb5/0x140 [ 33.979129] ip_local_out+0xc5/0x1b0 [ 33.982836] ip_queue_xmit+0x9df/0x1f80 [ 33.986820] ? ip_build_and_send_pkt+0xc80/0xc80 [ 33.991626] ? skb_send_sock+0x50/0x50 [ 33.995498] ? reqsk_fastopen_remove+0x651/0x680 [ 34.000335] ? dccp_insert_option_padding+0xbc/0xe0 [ 34.005355] ? dccp_v4_send_check+0x1a6/0x3d0 [ 34.009838] dccp_transmit_skb+0x999/0x12e0 [ 34.014151] dccp_xmit_packet+0x25e/0x7b0 [ 34.018281] ? dccp_send_sync+0x270/0x270 [ 34.022641] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 34.027696] ? ccid3_hc_tx_send_packet+0x35a/0x880 [ 34.032621] dccp_write_xmit+0x190/0x1f0 [ 34.036670] dccp_sendmsg+0x8db/0x1030 [ 34.040767] ? dccp_getsockopt+0xf0/0xf0 [ 34.044813] ? rw_copy_check_uvector+0x30d/0x3e0 [ 34.049555] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 34.055078] ? import_iovec+0x269/0x470 [ 34.059046] ? dup_iter+0x270/0x270 [ 34.062666] inet_sendmsg+0x1a1/0x690 [ 34.066452] ? copy_msghdr_from_user+0x3c4/0x580 [ 34.071192] ? ipip_gro_receive+0x100/0x100 [ 34.075502] ? move_addr_to_kernel.part.20+0x100/0x100 [ 34.080770] ? security_socket_sendmsg+0x94/0xc0 [ 34.085512] ? ipip_gro_receive+0x100/0x100 [ 34.089832] sock_sendmsg+0xd5/0x120 [ 34.093533] ___sys_sendmsg+0x7fd/0x930 [ 34.097504] ? copy_msghdr_from_user+0x580/0x580 [ 34.102266] ? kasan_check_read+0x11/0x20 [ 34.106401] ? __local_bh_enable_ip+0x161/0x230 [ 34.111060] ? __fget_light+0x2f7/0x440 [ 34.115027] ? trace_hardirqs_on+0xd/0x10 [ 34.119184] ? fget_raw+0x20/0x20 [ 34.122623] ? release_sock+0x1ec/0x2c0 [ 34.126584] ? __release_sock+0x3a0/0x3a0 [ 34.130717] ? __local_bh_enable_ip+0x161/0x230 [ 34.135393] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 34.140931] ? sockfd_lookup_light+0xc5/0x160 [ 34.145411] __sys_sendmsg+0x11d/0x290 [ 34.149284] ? __ia32_sys_shutdown+0x80/0x80 [ 34.153695] ? __x64_sys_futex+0x47f/0x6a0 [ 34.157929] ? __sys_listen+0x23e/0x380 [ 34.161909] ? ksys_ioctl+0x81/0xd0 [ 34.165522] __x64_sys_sendmsg+0x78/0xb0 [ 34.169585] do_syscall_64+0x1b9/0x820 [ 34.173456] ? finish_task_switch+0x1d3/0x870 [ 34.177954] ? syscall_return_slowpath+0x5e0/0x5e0 [ 34.182868] ? syscall_return_slowpath+0x31d/0x5e0 [ 34.187786] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 34.193167] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 34.198003] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 34.203186] RIP: 0033:0x446aa9 [ 34.206369] Code: e8 cc b8 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 0b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 34.225566] RSP: 002b:00007f6f91745da8 EFLAGS: 00000293 ORIG_RAX: 000000000000002e [ 34.233273] RAX: ffffffffffffffda RBX: 00000000006dec48 RCX: 0000000000446aa9 [ 34.240526] RDX: 0000000004000080 RSI: 00000000200030c0 RDI: 0000000000000005 [ 34.247778] RBP: 00000000006dec40 R08: 0000000000000000 R09: 0000000000000000 [ 34.255049] R10: 0000000000000000 R11: 0000000000000293 R12: 00000000006dec4c [ 34.262323] R13: 00000000004b0220 R14: 0000000020001f80 R15: 0000000000000000 [