[....] Starting OpenBSD Secure Shell server: sshd[ 20.317729] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 23.739973] random: sshd: uninitialized urandom read (32 bytes read) [ 23.988750] sshd (4385) used greatest stack depth: 16840 bytes left [ 24.010278] random: sshd: uninitialized urandom read (32 bytes read) [ 24.517778] random: sshd: uninitialized urandom read (32 bytes read) [ 28.030596] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.27' (ECDSA) to the list of known hosts. [ 33.454189] random: sshd: uninitialized urandom read (32 bytes read) [ 33.553104] IPVS: ftp: loaded support on port[0] = 21 [ 33.689612] bridge0: port 1(bridge_slave_0) entered blocking state [ 33.696097] bridge0: port 1(bridge_slave_0) entered disabled state [ 33.703660] device bridge_slave_0 entered promiscuous mode [ 33.720381] bridge0: port 2(bridge_slave_1) entered blocking state [ 33.726780] bridge0: port 2(bridge_slave_1) entered disabled state [ 33.733920] device bridge_slave_1 entered promiscuous mode [ 33.749960] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 33.766546] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 33.807941] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 33.826449] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 33.891095] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 33.898532] team0: Port device team_slave_0 added [ 33.913191] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 33.920550] team0: Port device team_slave_1 added [ 33.935676] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 33.952499] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 33.968450] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 33.984498] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready RTNETLINK answers: Operation not supported [ 34.064966] ip (4474) used greatest stack depth: 16280 bytes left [ 34.099434] bridge0: port 2(bridge_slave_1) entered blocking state [ 34.105877] bridge0: port 2(bridge_slave_1) entered forwarding state RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 34.112690] bridge0: port 1(bridge_slave_0) entered blocking state [ 34.119057] 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 [ 34.534761] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 34.540900] 8021q: adding VLAN 0 to HW filter on device bond0 [ 34.584976] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 34.628776] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 34.636359] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 34.674327] 8021q: adding VLAN 0 to HW filter on device team0 executing program [ 34.911151] 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() [ 34.924651] CPU: 1 PID: 4644 Comm: syz-executor622 Not tainted 4.18.0-rc8+ #49 [ 34.932078] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.941427] Call Trace: [ 34.943994] [ 34.946132] dump_stack+0x1c9/0x2b4 [ 34.949749] ? dump_stack_print_info.cold.2+0x52/0x52 [ 34.954953] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 34.960474] ? tfrc_rx_handle_loss+0x67c/0x1eb0 [ 34.965185] ? rcu_is_watching+0x8c/0x150 [ 34.969436] tfrc_rx_hist_sample_rtt.cold.3+0x54/0x5c [ 34.974679] ccid3_hc_rx_packet_recv+0x5c4/0xeb0 [ 34.979453] ? dccp_parse_options+0x493/0x11f0 [ 34.984039] ? ccid3_hc_tx_send_packet+0x880/0x880 [ 34.988951] dccp_deliver_input_to_ccids+0xf0/0x280 [ 34.993963] dccp_rcv_established+0x87/0xb0 [ 34.998285] dccp_v4_do_rcv+0x153/0x180 [ 35.002242] __sk_receive_skb+0x3c0/0xd90 [ 35.006377] ? __inet_lookup_established+0x462/0x690 [ 35.011464] ? sk_free+0x50/0x50 [ 35.014936] ? inet_lhash2_lookup+0x6e0/0x6e0 [ 35.019414] ? reqsk_fastopen_remove+0x680/0x680 [ 35.024152] ? lock_downgrade+0x8f0/0x8f0 [ 35.028290] ? dccp_invalid_packet+0x64/0x890 [ 35.032779] dccp_v4_rcv+0x10f9/0x1f58 [ 35.036657] ? dccp_v4_err+0x1860/0x1860 [ 35.040780] ? __lock_is_held+0xb5/0x140 [ 35.044836] ip_local_deliver_finish+0x2eb/0xda0 [ 35.049573] ? inet_add_protocol.cold.0+0x21/0x21 [ 35.054406] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 35.059423] ? nf_hook_slow+0x11e/0x1c0 [ 35.063379] ip_local_deliver+0x1e9/0x750 [ 35.067505] ? nf_conntrack_update+0xc80/0xc80 [ 35.072075] ? ip_call_ra_chain+0x730/0x730 [ 35.076384] ? inet_add_protocol.cold.0+0x21/0x21 [ 35.081208] ? graph_lock+0x170/0x170 [ 35.084999] ip_rcv_finish+0x823/0x2220 [ 35.088958] ? ip_local_deliver_finish+0xda0/0xda0 [ 35.093872] ? lock_downgrade+0x8f0/0x8f0 [ 35.098132] ? kasan_check_read+0x11/0x20 [ 35.102272] ? rcu_is_watching+0x8c/0x150 [ 35.106405] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 35.110801] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 35.115808] ? nf_hook_slow+0x11e/0x1c0 [ 35.119788] ip_rcv+0xa18/0x1284 [ 35.123142] ? ip_local_deliver+0x750/0x750 [ 35.127450] ? ip_local_deliver_finish+0xda0/0xda0 [ 35.132377] ? __lock_is_held+0xb5/0x140 [ 35.136426] ? ip_local_deliver+0x750/0x750 [ 35.140734] __netif_receive_skb_core+0x23d0/0x35b0 [ 35.145737] ? nf_ingress+0xa30/0xa30 [ 35.149524] ? __lock_acquire+0x7fc/0x5020 [ 35.153760] ? kasan_check_read+0x11/0x20 [ 35.157892] ? do_raw_spin_unlock+0xa7/0x2f0 [ 35.162319] ? trace_hardirqs_on+0x10/0x10 [ 35.166540] ? trace_hardirqs_off+0xd/0x10 [ 35.170759] ? _raw_spin_unlock_irqrestore+0x63/0xc0 [ 35.175857] ? try_to_wake_up+0x10a/0x12a0 [ 35.180100] ? print_usage_bug+0xc0/0xc0 [ 35.184157] ? graph_lock+0x170/0x170 [ 35.187943] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 35.193044] ? trace_hardirqs_on_caller+0x19e/0x5c0 [ 35.198060] ? trace_hardirqs_on+0xd/0x10 [ 35.202203] ? find_held_lock+0x36/0x1c0 [ 35.206318] ? print_usage_bug+0xc0/0xc0 [ 35.210372] ? lock_acquire+0x1e4/0x540 [ 35.214334] ? process_backlog+0x1a6/0x760 [ 35.218558] ? kasan_check_read+0x11/0x20 [ 35.222688] ? rcu_is_watching+0x8c/0x150 [ 35.226821] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 35.231226] __netif_receive_skb+0x2c/0x1e0 [ 35.235546] process_backlog+0x219/0x760 [ 35.239600] net_rx_action+0x7da/0x1980 [ 35.243569] ? napi_complete_done+0x6c0/0x6c0 [ 35.248072] ? rcu_read_lock_sched_held+0x108/0x120 [ 35.253080] ? rcu_process_callbacks+0x1251/0x1850 [ 35.258002] ? call_rcu_sched+0x20/0x20 [ 35.261977] ? load_balance+0x3640/0x3640 [ 35.266122] ? enqueue_hrtimer+0x18e/0x540 [ 35.270345] ? find_held_lock+0x36/0x1c0 [ 35.274391] ? print_usage_bug+0xc0/0xc0 [ 35.278437] ? graph_lock+0x170/0x170 [ 35.282229] ? run_rebalance_domains+0x365/0x4c0 [ 35.286973] ? __lock_is_held+0xb5/0x140 [ 35.291043] ? print_usage_bug+0xc0/0xc0 [ 35.295116] ? __do_softirq+0x780/0xb17 [ 35.299095] ? graph_lock+0x170/0x170 [ 35.302893] ? __irqentry_text_end+0x1f97a8/0x1f97a8 [ 35.307992] ? __lock_is_held+0xb5/0x140 [ 35.312065] __do_softirq+0x2e8/0xb17 [ 35.315859] ? __irqentry_text_end+0x1f97a8/0x1f97a8 [ 35.320947] ? irq_exit+0xbb/0x210 [ 35.324470] ? smp_apic_timer_interrupt+0x186/0x730 [ 35.329485] ? smp_call_function_single_interrupt+0x660/0x660 [ 35.335364] ? _raw_spin_unlock+0x22/0x30 [ 35.339501] ? handle_edge_irq+0x330/0x870 [ 35.343723] ? task_prio+0x50/0x50 [ 35.347257] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 35.352088] do_softirq_own_stack+0x2a/0x40 [ 35.356388] [ 35.358699] do_softirq.part.17+0x155/0x1a0 [ 35.363020] ? ip_finish_output2+0xa87/0x1860 [ 35.367528] __local_bh_enable_ip+0x1ec/0x230 [ 35.372011] ip_finish_output2+0xaba/0x1860 [ 35.376346] ? ip_copy_metadata+0xb30/0xb30 [ 35.380656] ? graph_lock+0x170/0x170 [ 35.384509] ? nf_ct_deliver_cached_events+0x558/0x7d0 [ 35.389852] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 35.395482] ? ipv4_mtu+0x37d/0x590 [ 35.399114] ? __lock_is_held+0xb5/0x140 [ 35.403192] ip_finish_output+0x841/0xfa0 [ 35.407334] ? ip_finish_output+0x841/0xfa0 [ 35.411651] ? ip_fragment.constprop.49+0x240/0x240 [ 35.416653] ? kasan_check_read+0x11/0x20 [ 35.420786] ? rcu_is_watching+0x8c/0x150 [ 35.424916] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 35.429312] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 35.434313] ? nf_hook_slow+0x11e/0x1c0 [ 35.438274] ip_output+0x223/0x880 [ 35.441798] ? __ip_local_out+0x5e3/0xb50 [ 35.445930] ? ip_mc_output+0x15d0/0x15d0 [ 35.450072] ? ip_fragment.constprop.49+0x240/0x240 [ 35.455075] ? __lock_is_held+0xb5/0x140 [ 35.459191] ip_local_out+0xc5/0x1b0 [ 35.462897] ip_queue_xmit+0x9df/0x1f80 [ 35.466863] ? ip_build_and_send_pkt+0xc80/0xc80 [ 35.471604] ? skb_send_sock+0x50/0x50 [ 35.475478] ? reqsk_fastopen_remove+0x651/0x680 [ 35.480222] ? dccp_insert_option_padding+0xbc/0xe0 [ 35.485284] ? dccp_v4_send_check+0x1a6/0x3d0 [ 35.489774] dccp_transmit_skb+0x999/0x12e0 [ 35.494087] dccp_xmit_packet+0x25e/0x7b0 [ 35.498225] ? dccp_send_sync+0x270/0x270 [ 35.502366] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 35.507369] ? ccid3_hc_tx_send_packet+0x35a/0x880 [ 35.512286] dccp_write_xmit+0x190/0x1f0 [ 35.516344] dccp_sendmsg+0x8db/0x1030 [ 35.520224] ? dccp_getsockopt+0xf0/0xf0 [ 35.524339] ? rw_copy_check_uvector+0x30d/0x3e0 [ 35.529097] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 35.534661] ? import_iovec+0x269/0x470 [ 35.538627] ? dup_iter+0x270/0x270 [ 35.542249] inet_sendmsg+0x1a1/0x690 [ 35.546049] ? copy_msghdr_from_user+0x3c4/0x580 [ 35.550806] ? ipip_gro_receive+0x100/0x100 [ 35.555119] ? move_addr_to_kernel.part.20+0x100/0x100 [ 35.560385] ? security_socket_sendmsg+0x94/0xc0 [ 35.565131] ? ipip_gro_receive+0x100/0x100 [ 35.569439] sock_sendmsg+0xd5/0x120 [ 35.573143] ___sys_sendmsg+0x7fd/0x930 [ 35.577108] ? copy_msghdr_from_user+0x580/0x580 [ 35.581859] ? kasan_check_read+0x11/0x20 [ 35.585995] ? __local_bh_enable_ip+0x161/0x230 [ 35.590656] ? __fget_light+0x2f7/0x440 [ 35.594623] ? trace_hardirqs_on+0xd/0x10 [ 35.598756] ? fget_raw+0x20/0x20 [ 35.602197] ? release_sock+0x1ec/0x2c0 [ 35.606161] ? __release_sock+0x3a0/0x3a0 [ 35.610299] ? __local_bh_enable_ip+0x161/0x230 [ 35.614965] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 35.620487] ? sockfd_lookup_light+0xc5/0x160 [ 35.624969] __sys_sendmsg+0x11d/0x290 [ 35.628850] ? __ia32_sys_shutdown+0x80/0x80 [ 35.633247] ? __x64_sys_futex+0x47f/0x6a0 [ 35.637464] ? __sys_listen+0x23e/0x380 [ 35.641432] ? _raw_spin_unlock_irq+0x27/0x70 [ 35.645914] __x64_sys_sendmsg+0x78/0xb0 [ 35.649962] do_syscall_64+0x1b9/0x820 [ 35.653839] ? syscall_return_slowpath+0x5e0/0x5e0 [ 35.658857] ? syscall_return_slowpath+0x31d/0x5e0 [ 35.663792] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 35.669153] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 35.673986] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 35.679173] RIP: 0033:0x446a59 [ 35.682396] 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 [ 35.701648] RSP: 002b:00007f4646efeda8 EFLAGS: 00000293 ORIG_RAX: 000000000000002e [ 35.709345] RAX: ffffffffffffffda RBX: 00000000006dec58 RCX: 0000000000446a59 [ 35.716601] RDX: 0000000004000080 RSI: 00000000200030c0 RDI: 0000000000000005 [ 35.723856] RBP: 00000000006dec50 R08: 0000000000000000 R09: 0000000000000000 [ 35.731111] R10: 0000000000000000 R11: 0000000000000293 R12: 00000000006dec5c [ 35.738362] R13: 00000000004b01f0 R14: 0000000020001f80 R15: 0000000000000001 [