[ OK ] Started Getty on tty5. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.136' (ECDSA) to the list of known hosts. syzkaller login: [ 35.520967] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 35.627016] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. [ 35.644714] skbuff: skb_under_panic: text:00000000e93ca143 len:48 put:8 head:00000000946fb9c9 data:0000000094f10a8e tail:0x2c end:0xc0 dev:sit1 [ 35.658215] ------------[ cut here ]------------ [ 35.662967] kernel BUG at net/core/skbuff.c:104! [ 35.667755] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 35.673111] CPU: 1 PID: 8171 Comm: syz-executor886 Not tainted 4.19.211-syzkaller #0 [ 35.680966] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 35.690320] RIP: 0010:skb_panic+0x172/0x174 [ 35.694619] Code: 4c 24 10 8b 8b 80 00 00 00 41 56 45 89 e8 4c 89 e2 41 57 48 89 ee 48 c7 c7 60 4f 4c 89 ff 74 24 10 ff 74 24 20 e8 f1 18 e2 ff <0f> 0b e8 7f e7 50 f9 4c 8b 64 24 18 e8 c5 aa 86 f9 48 c7 c1 c0 58 [ 35.713496] RSP: 0018:ffff888091c4eb30 EFLAGS: 00010282 [ 35.718834] RAX: 0000000000000083 RBX: ffff8880a2c5c200 RCX: 0000000000000000 [ 35.726079] RDX: 0000000000000000 RSI: ffffffff814dff01 RDI: ffffed1012389d58 [ 35.733326] RBP: ffffffff894c58c0 R08: 0000000000000083 R09: 0000000000000000 [ 35.740574] R10: 0000000000000005 R11: 0000000000000000 R12: ffffffff86eec28f [ 35.747831] R13: 0000000000000008 R14: ffff8880b0566700 R15: 00000000000000c0 [ 35.755080] FS: 00005555558d8300(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 [ 35.763286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 35.769144] CR2: 0000000000000000 CR3: 000000009bb95000 CR4: 00000000003406e0 [ 35.776395] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 35.783641] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 35.790889] Call Trace: [ 35.793466] ? gue_encap_hlen+0x70/0x70 [ 35.797420] ? fou_build_udp+0x2f/0x360 [ 35.801374] skb_push.cold+0x24/0x24 [ 35.805077] fou_build_udp+0x2f/0x360 [ 35.808856] gue_build_header+0xf7/0x140 [ 35.812894] ? fou_build_udp+0x360/0x360 [ 35.817556] ? check_preemption_disabled+0x41/0x280 [ 35.822549] ? fou_build_udp+0x360/0x360 [ 35.826586] ip_tunnel_xmit+0x7ed/0x3850 [ 35.830627] ? ip_md_tunnel_xmit+0x12a0/0x12a0 [ 35.835191] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 35.840358] sit_tunnel_xmit+0x4ef/0x28d0 [ 35.844485] ? sit_init_net+0xa10/0xa10 [ 35.848451] ? netif_skb_features+0x5c1/0xb30 [ 35.852929] ? check_preemption_disabled+0x41/0x280 [ 35.857925] dev_hard_start_xmit+0x1a8/0x920 [ 35.862311] __dev_queue_xmit+0x269d/0x2e00 [ 35.866611] ? __neigh_create+0x7d9/0x1c40 [ 35.870825] ? __local_bh_enable_ip+0x159/0x270 [ 35.875484] ? netdev_pick_tx+0x2f0/0x2f0 [ 35.879610] ? lockdep_hardirqs_on+0x288/0x5c0 [ 35.884187] ? __neigh_create+0x11c9/0x1c40 [ 35.888485] ? __local_bh_enable_ip+0xb0/0x270 [ 35.893044] ? __neigh_create+0xb8e/0x1c40 [ 35.897256] ? nf_ct_deliver_cached_events+0x205/0x630 [ 35.902525] ip_finish_output2+0xd76/0x15a0 [ 35.906837] ? nf_conntrack_eventmask_report+0x700/0x700 [ 35.912276] ? netif_rx_ni+0xc8/0x350 [ 35.916055] ? ip_send_check+0xb0/0xb0 [ 35.919920] ? ip_mc_output+0x68d/0xec0 [ 35.923872] ip_finish_output+0xae9/0x10b0 [ 35.928083] ip_mc_output+0x268/0xec0 [ 35.931859] ? __ip_queue_xmit+0x1c10/0x1c10 [ 35.936245] ? ip_fragment.constprop.0+0x240/0x240 [ 35.941152] ? ip_do_fragment+0x2620/0x2620 [ 35.945461] ip_local_out+0xaf/0x170 [ 35.949155] ip_send_skb+0x3e/0xe0 [ 35.952686] udp_send_skb+0x6a4/0x1170 [ 35.956552] udp_sendmsg+0x1cb4/0x2550 [ 35.960423] ? ip_do_fragment+0x2620/0x2620 [ 35.964720] ? __save_stack_trace+0x72/0x190 [ 35.969106] ? udp_seq_next+0x80/0x80 [ 35.972885] ? __read_once_size_nocheck.constprop.0+0x10/0x10 [ 35.978745] ? deref_stack_reg+0x1d0/0x1d0 [ 35.982973] ? static_obj+0x50/0x50 [ 35.986577] ? mesh_queue_preq+0x44e/0x620 [ 35.990791] ? __lock_acquire+0x6de/0x3ff0 [ 35.995003] ? __save_stack_trace+0xaf/0x190 [ 35.999414] udpv6_sendmsg+0x14b2/0x2ae0 [ 36.003457] ? udp_v6_push_pending_frames+0x360/0x360 [ 36.008623] ? mark_held_locks+0xf0/0xf0 [ 36.012664] ? mark_held_locks+0xf0/0xf0 [ 36.016700] ? mark_held_locks+0xa6/0xf0 [ 36.020739] ? mark_held_locks+0xf0/0xf0 [ 36.024779] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 36.029346] ? reacquire_held_locks+0xb5/0x430 [ 36.033916] ? release_sock+0x1b/0x1b0 [ 36.037784] ? ip6_datagram_release_cb+0x2e7/0x540 [ 36.042693] ? inet_autobind+0x130/0x190 [ 36.046732] ? lock_downgrade+0x720/0x720 [ 36.050859] ? __local_bh_enable_ip+0x159/0x270 [ 36.055504] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 36.060064] ? inet_autobind+0x130/0x190 [ 36.064104] inet_sendmsg+0x132/0x5a0 [ 36.067885] ? security_socket_sendmsg+0x83/0xb0 [ 36.072617] ? inet_recvmsg+0x5c0/0x5c0 [ 36.076570] sock_sendmsg+0xc3/0x120 [ 36.080268] ___sys_sendmsg+0x3b3/0x8e0 [ 36.084229] ? copy_msghdr_from_user+0x440/0x440 [ 36.088962] ? aa_af_perm+0x230/0x230 [ 36.092738] ? nlmsg_notify+0x1f0/0x1f0 [ 36.096687] ? kernel_recvmsg+0x220/0x220 [ 36.100821] ? check_preemption_disabled+0x41/0x280 [ 36.105823] ? ___sys_sendmsg+0x4ba/0x8e0 [ 36.109947] ? rcu_read_lock_sched_held+0x16c/0x1d0 [ 36.114942] ? ___sys_sendmsg+0x4bf/0x8e0 [ 36.119071] ? mark_held_locks+0xf0/0xf0 [ 36.123110] ? copy_msghdr_from_user+0x440/0x440 [ 36.127844] ? lock_downgrade+0x720/0x720 [ 36.131969] ? __fdget+0x1a0/0x230 [ 36.135486] __sys_sendmmsg+0x195/0x470 [ 36.139438] ? __ia32_sys_sendmsg+0x220/0x220 [ 36.143924] ? __fdget+0x1a0/0x230 [ 36.147450] ? __x64_sys_sendmsg+0x159/0x220 [ 36.151837] ? __sys_sendmsg+0x1b0/0x1b0 [ 36.155889] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 36.161232] __x64_sys_sendmmsg+0x99/0x100 [ 36.165457] ? lockdep_hardirqs_on+0x3a8/0x5c0 [ 36.170018] do_syscall_64+0xf9/0x620 [ 36.173817] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.178984] RIP: 0033:0x7f60d3630499 [ 36.182691] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 36.201570] RSP: 002b:00007ffcd81b9eb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 [ 36.209259] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f60d3630499 [ 36.216505] RDX: 0000000000000001 RSI: 00000000200017c0 RDI: 0000000000000003 [ 36.223751] RBP: 0000000000000000 R08: 00000000d369de40 R09: 00000000d369de40 [ 36.230997] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000008b1f [ 36.238244] R13: 00007ffcd81b9ee0 R14: 00007ffcd81b9ed0 R15: 00007ffcd81b9ec4 [ 36.245492] Modules linked in: [ 36.248715] ---[ end trace 70e215b8f1dc5818 ]--- [ 36.253476] RIP: 0010:skb_panic+0x172/0x174 [ 36.257834] Code: 4c 24 10 8b 8b 80 00 00 00 41 56 45 89 e8 4c 89 e2 41 57 48 89 ee 48 c7 c7 60 4f 4c 89 ff 74 24 10 ff 74 24 20 e8 f1 18 e2 ff <0f> 0b e8 7f e7 50 f9 4c 8b 64 24 18 e8 c5 aa 86 f9 48 c7 c1 c0 58 [ 36.276767] RSP: 0018:ffff888091c4eb30 EFLAGS: 00010282 [ 36.282127] RAX: 0000000000000083 RBX: ffff8880a2c5c200 RCX: 0000000000000000 [ 36.289432] RDX: 0000000000000000 RSI: ffffffff814dff01 RDI: ffffed1012389d58 [ 36.296756] RBP: ffffffff894c58c0 R08: 0000000000000083 R09: 0000000000000000 [ 36.304012] R10: 0000000000000005 R11: 0000000000000000 R12: ffffffff86eec28f [ 36.311293] R13: 0000000000000008 R14: ffff8880b0566700 R15: 00000000000000c0 [ 36.318587] FS: 00005555558d8300(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 [ 36.326835] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 36.332717] CR2: 0000000000000000 CR3: 000000009bb95000 CR4: 00000000003406e0 [ 36.340005] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 36.347302] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 36.354559] Kernel panic - not syncing: Fatal exception in interrupt [ 36.361183] Kernel Offset: disabled [ 36.364792] Rebooting in 86400 seconds..