[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 23.033762] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 24.123998] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 24.445482] random: sshd: uninitialized urandom read (32 bytes read) [ 25.022402] random: sshd: uninitialized urandom read (32 bytes read) [ 25.203697] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.51' (ECDSA) to the list of known hosts. [ 30.856465] random: sshd: uninitialized urandom read (32 bytes read) [ 30.959480] IPVS: ftp: loaded support on port[0] = 21 [ 31.093956] bridge0: port 1(bridge_slave_0) entered blocking state [ 31.100564] bridge0: port 1(bridge_slave_0) entered disabled state [ 31.108435] device bridge_slave_0 entered promiscuous mode [ 31.125146] bridge0: port 2(bridge_slave_1) entered blocking state [ 31.131550] bridge0: port 2(bridge_slave_1) entered disabled state [ 31.138877] device bridge_slave_1 entered promiscuous mode [ 31.155879] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 31.172199] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 31.215931] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 31.235756] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 31.302073] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 31.309389] team0: Port device team_slave_0 added [ 31.324346] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 31.331539] team0: Port device team_slave_1 added [ 31.346994] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 31.366392] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 31.384601] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 31.402267] 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 [ 31.527225] bridge0: port 2(bridge_slave_1) entered blocking state [ 31.533666] bridge0: port 2(bridge_slave_1) entered forwarding state [ 31.540663] bridge0: port 1(bridge_slave_0) entered blocking state [ 31.547060] 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 [ 31.989885] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 31.996002] 8021q: adding VLAN 0 to HW filter on device bond0 [ 32.041312] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 32.075940] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 32.096404] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 32.102763] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 32.110073] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 32.151313] 8021q: adding VLAN 0 to HW filter on device team0 executing program [ 32.429244] 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() [ 32.442592] CPU: 1 PID: 4895 Comm: syz-executor193 Not tainted 4.19.0-rc1+ #216 [ 32.450027] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.459369] Call Trace: [ 32.461935] [ 32.464078] dump_stack+0x1c9/0x2b4 [ 32.467694] ? dump_stack_print_info.cold.2+0x52/0x52 [ 32.472895] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.478423] ? tfrc_rx_handle_loss+0x67c/0x1eb0 [ 32.483077] ? rcu_is_watching+0x8c/0x150 [ 32.487216] tfrc_rx_hist_sample_rtt.cold.3+0x54/0x5c [ 32.492396] ccid3_hc_rx_packet_recv+0x5c4/0xeb0 [ 32.497138] ? dccp_parse_options+0x493/0x11f0 [ 32.501711] ? ccid3_hc_tx_send_packet+0x880/0x880 [ 32.506626] dccp_deliver_input_to_ccids+0xf0/0x280 [ 32.511631] dccp_rcv_established+0x87/0xb0 [ 32.515942] dccp_v4_do_rcv+0x153/0x180 [ 32.519906] __sk_receive_skb+0x3e5/0xec0 [ 32.524063] ? sk_free+0x50/0x50 [ 32.527424] ? inet_lhash2_lookup+0x6e0/0x6e0 [ 32.531906] ? reqsk_fastopen_remove+0x680/0x680 [ 32.536664] ? lock_downgrade+0x8f0/0x8f0 [ 32.540803] ? dccp_invalid_packet+0x64/0x890 [ 32.545674] dccp_v4_rcv+0x10f9/0x1f58 [ 32.549571] ? dccp_v4_err+0x1860/0x1860 [ 32.553633] ? __lock_is_held+0xb5/0x140 [ 32.557688] ip_local_deliver_finish+0x2eb/0xda0 [ 32.562434] ? ip_sublist_rcv_finish+0x3e0/0x3e0 [ 32.567176] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 32.572176] ? nf_hook_slow+0x11e/0x1c0 [ 32.576138] ip_local_deliver+0x1e9/0x750 [ 32.580279] ? ip_call_ra_chain+0x730/0x730 [ 32.584592] ? ip_sublist_rcv_finish+0x3e0/0x3e0 [ 32.589335] ? kasan_check_read+0x11/0x20 [ 32.593469] ? rcu_is_watching+0x8c/0x150 [ 32.597626] ? rcu_cleanup_dead_rnp+0x200/0x200 [ 32.602281] ip_rcv_finish+0x1f9/0x300 [ 32.606165] ip_rcv+0xed/0x610 [ 32.609352] ? ip_local_deliver+0x750/0x750 [ 32.613663] ? ip_rcv_finish_core.isra.16+0x1f10/0x1f10 [ 32.619013] ? lock_acquire+0x1e4/0x4f0 [ 32.622977] __netif_receive_skb_one_core+0x14d/0x200 [ 32.628153] ? __netif_receive_skb_core+0x39f0/0x39f0 [ 32.633328] ? net_rx_action+0x799/0x1900 [ 32.637461] ? rcu_cleanup_dead_rnp+0x200/0x200 [ 32.642118] __netif_receive_skb+0x2c/0x1e0 [ 32.646430] process_backlog+0x219/0x760 [ 32.650489] net_rx_action+0x799/0x1900 [ 32.654477] ? napi_complete_done+0x6d0/0x6d0 [ 32.658976] ? mark_held_locks+0x160/0x160 [ 32.663202] ? rcu_cleanup_dead_rnp+0x200/0x200 [ 32.667874] ? rebalance_domains+0x379/0xd90 [ 32.672277] ? load_balance+0x3640/0x3640 [ 32.676430] ? enqueue_hrtimer+0x187/0x4e0 [ 32.680650] ? lock_release+0x9f0/0x9f0 [ 32.684619] ? hrtimer_update_softirq_timer+0xa0/0xa0 [ 32.689803] ? graph_lock+0x170/0x170 [ 32.693598] ? find_held_lock+0x36/0x1c0 [ 32.697647] ? print_usage_bug+0xc0/0xc0 [ 32.701705] ? lock_downgrade+0x8f0/0x8f0 [ 32.705847] ? graph_lock+0x170/0x170 [ 32.709646] ? mark_held_locks+0xc9/0x160 [ 32.713779] ? scheduler_ipi+0x1a8/0xa50 [ 32.717828] ? __do_softirq+0x278/0xa74 [ 32.721800] ? __lock_is_held+0xb5/0x140 [ 32.725860] __do_softirq+0x2eb/0xa74 [ 32.729657] ? __irqentry_text_end+0x1f9f00/0x1f9f00 [ 32.734748] ? smp_reschedule_interrupt+0xfd/0x5e0 [ 32.739663] ? smp_thermal_interrupt+0x710/0x710 [ 32.744402] ? ret_from_intr+0xb/0x1e [ 32.748212] ? trace_hardirqs_off_caller+0xbb/0x2b0 [ 32.753212] ? trace_hardirqs_off+0xb8/0x2b0 [ 32.757608] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.762436] ? trace_hardirqs_on_caller+0x2b0/0x2b0 [ 32.767463] ? task_prio+0x50/0x50 [ 32.770997] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.775858] do_softirq_own_stack+0x2a/0x40 [ 32.780190] [ 32.782440] do_softirq.part.18+0x157/0x1a0 [ 32.786749] ? ip_finish_output2+0xa87/0x1860 [ 32.791231] __local_bh_enable_ip+0x1ee/0x230 [ 32.795733] ip_finish_output2+0xaba/0x1860 [ 32.800046] ? ip_copy_metadata+0xe20/0xe20 [ 32.804354] ? graph_lock+0x170/0x170 [ 32.808149] ? nf_ct_deliver_cached_events+0x293/0x7e0 [ 32.813437] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.818963] ? ipv4_mtu+0x37d/0x590 [ 32.822578] ? __lock_is_held+0xb5/0x140 [ 32.826631] ip_finish_output+0x841/0xfa0 [ 32.830787] ? ip_finish_output+0x841/0xfa0 [ 32.835097] ? ip_fragment.constprop.49+0x240/0x240 [ 32.840104] ? kasan_check_read+0x11/0x20 [ 32.844237] ? rcu_is_watching+0x8c/0x150 [ 32.848376] ? rcu_cleanup_dead_rnp+0x200/0x200 [ 32.853035] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 32.858042] ? nf_hook_slow+0x11e/0x1c0 [ 32.862007] ip_output+0x223/0x880 [ 32.865538] ? __ip_local_out+0x5e3/0xb50 [ 32.869687] ? ip_mc_output+0x15d0/0x15d0 [ 32.873822] ? ip_fragment.constprop.49+0x240/0x240 [ 32.878822] ? __lock_is_held+0xb5/0x140 [ 32.882879] ? ipoib_reap_ah+0x5f0/0x980 [ 32.886932] ip_local_out+0xc5/0x1b0 [ 32.890631] __ip_queue_xmit+0x9b6/0x1f20 [ 32.894769] ? ip_build_and_send_pkt+0xc80/0xc80 [ 32.899521] ? __skb_checksum+0x8f0/0x8f0 [ 32.903666] ? skb_send_sock+0x50/0x50 [ 32.907544] ? reqsk_fastopen_remove+0x680/0x680 [ 32.912290] ? dccp_insert_option_padding+0xbc/0xe0 [ 32.917315] ip_queue_xmit+0x56/0x70 [ 32.921033] dccp_transmit_skb+0x999/0x12e0 [ 32.925346] dccp_xmit_packet+0x25e/0x7d0 [ 32.929486] ? kasan_check_write+0x14/0x20 [ 32.933719] ? do_raw_spin_lock+0xc1/0x200 [ 32.937939] ? dccp_send_sync+0x270/0x270 [ 32.942075] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 32.947077] ? ccid3_hc_tx_send_packet+0x35a/0x880 [ 32.951996] dccp_write_xmit+0x190/0x1f0 [ 32.956043] dccp_sendmsg+0xd32/0xf90 [ 32.959832] ? dccp_getsockopt+0xf0/0xf0 [ 32.963898] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 32.968812] ? aa_sk_perm+0x20c/0x8a0 [ 32.972601] ? import_iovec+0x269/0x470 [ 32.976566] ? aa_af_perm+0x5a0/0x5a0 [ 32.980394] inet_sendmsg+0x1a1/0x690 [ 32.984184] ? ipip_gro_receive+0x100/0x100 [ 32.988500] ? apparmor_socket_sendmsg+0x29/0x30 [ 32.993260] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.998785] ? security_socket_sendmsg+0x94/0xc0 [ 33.003536] ? ipip_gro_receive+0x100/0x100 [ 33.007868] sock_sendmsg+0xd5/0x120 [ 33.011572] ___sys_sendmsg+0x7fd/0x930 [ 33.015544] ? copy_msghdr_from_user+0x580/0x580 [ 33.020288] ? _raw_spin_unlock_bh+0x30/0x40 [ 33.024684] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 33.029774] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 33.034345] ? __fget_light+0x2f7/0x440 [ 33.038313] ? fget_raw+0x20/0x20 [ 33.041788] ? release_sock+0x1ec/0x2c0 [ 33.045751] ? kasan_check_write+0x14/0x20 [ 33.049972] ? __release_sock+0x3a0/0x3a0 [ 33.054108] ? __local_bh_enable_ip+0x161/0x230 [ 33.058803] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 33.064351] ? sockfd_lookup_light+0xc5/0x160 [ 33.068842] __sys_sendmsg+0x11d/0x290 [ 33.072732] ? __ia32_sys_shutdown+0x80/0x80 [ 33.077131] ? __x64_sys_futex+0x47f/0x6a0 [ 33.081352] ? do_syscall_64+0x9a/0x820 [ 33.085315] ? do_syscall_64+0x9a/0x820 [ 33.089278] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 33.094370] ? trace_hardirqs_off+0xb8/0x2b0 [ 33.098769] __x64_sys_sendmsg+0x78/0xb0 [ 33.102818] do_syscall_64+0x1b9/0x820 [ 33.106692] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 33.112045] ? syscall_return_slowpath+0x5e0/0x5e0 [ 33.116961] ? trace_hardirqs_on_caller+0x2b0/0x2b0 [ 33.121966] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 33.126992] ? recalc_sigpending_tsk+0x180/0x180 [ 33.131739] ? kasan_check_write+0x14/0x20 [ 33.135964] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.140798] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 33.145971] RIP: 0033:0x446e29 [ 33.149149] 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 [ 33.168060] RSP: 002b:00007fadfb787da8 EFLAGS: 00000293 ORIG_RAX: 000000000000002e [ 33.175755] RAX: ffffffffffffffda RBX: 00000000006dcc68 RCX: 0000000000446e29 [ 33.183012] RDX: 0000000000000800 RSI: 00000000200004c0 RDI: 0000000000000005 [ 33.190266] RBP: 00000000006dcc60 R08: 0000000000000000 R09: 0000000000000000 [ 33.197532] R10: 0000000000000000 R11: 0000000000000293 R12: 00000000006dcc6c [ 33.204796] R13: 00000000004af520 R14: 0000000020000780 R15: 0000000000000005