Warning: Permanently added '10.128.0.95' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 28.181819] skbuff: skb_under_panic: text:ffffffff86255e1f len:48 put:8 head:ffff8880a5402300 data:ffff8880a54022fc tail:0x2c end:0xc0 dev:sit1 [ 28.195122] ------------[ cut here ]------------ [ 28.199878] kernel BUG at net/core/skbuff.c:104! [ 28.204867] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 28.210217] Modules linked in: [ 28.213397] CPU: 1 PID: 7958 Comm: syz-executor133 Not tainted 4.14.304-syzkaller #0 [ 28.221263] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 [ 28.230608] task: ffff888097ffa240 task.stack: ffff8880962a8000 [ 28.236666] RIP: 0010:skb_panic+0x172/0x174 [ 28.240976] RSP: 0018:ffff8880962aee78 EFLAGS: 00010282 [ 28.246322] RAX: 0000000000000083 RBX: ffff8880ab7c2140 RCX: 0000000000000000 [ 28.253567] RDX: 0000000000000000 RSI: ffffffff878bd020 RDI: ffffed1012c55dc5 [ 28.260812] RBP: ffffffff8855e7a0 R08: 0000000000000083 R09: 0000000000000000 [ 28.268170] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff86255e1f [ 28.275414] R13: 0000000000000008 R14: ffff8880b3f0ae40 R15: 00000000000000c0 [ 28.282657] FS: 00005555570fe300(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 [ 28.290855] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.296708] CR2: 0000000000000000 CR3: 0000000094725000 CR4: 00000000003406e0 [ 28.303951] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 28.311217] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 28.318458] Call Trace: [ 28.321036] ? fou_build_udp+0x2f/0x360 [ 28.324982] skb_push.cold+0x24/0x24 [ 28.328669] fou_build_udp+0x2f/0x360 [ 28.332441] gue_build_header+0xd1/0x110 [ 28.336504] ? fou_build_udp+0x360/0x360 [ 28.340538] ? fou_build_udp+0x360/0x360 [ 28.344595] ip_tunnel_xmit+0x50e/0x33e0 [ 28.348634] ? ip_md_tunnel_xmit+0x1060/0x1060 [ 28.353191] ? __lock_acquire+0x5fc/0x3f20 [ 28.357401] ? __lock_acquire+0x5fc/0x3f20 [ 28.361606] ? iptunnel_handle_offloads+0x32e/0x500 [ 28.366611] sit_tunnel_xmit+0x1ab/0x2130 [ 28.370732] ? trace_hardirqs_on+0x10/0x10 [ 28.374947] ? skb_crc32c_csum_help+0x70/0x70 [ 28.379429] ? sit_init_net+0x820/0x820 [ 28.383380] ? inet_addr_type_dev_table+0x2d6/0x480 [ 28.388393] ? netif_skb_features+0x4ed/0x9f0 [ 28.392868] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 28.398290] dev_hard_start_xmit+0x188/0x890 [ 28.402681] __dev_queue_xmit+0x1d7f/0x2480 [ 28.406985] ? trace_hardirqs_on_caller+0x288/0x580 [ 28.411981] ? __neigh_create+0x1022/0x19c0 [ 28.416281] ? netdev_pick_tx+0x2e0/0x2e0 [ 28.420593] ? __neigh_create+0xadb/0x19c0 [ 28.424805] ? check_preemption_disabled+0x35/0x240 [ 28.429801] ip_finish_output2+0xba6/0x1340 [ 28.434096] ? ip_send_check+0xb0/0xb0 [ 28.437960] ip_finish_output+0x37c/0xc50 [ 28.442106] ip_output+0x1cd/0x510 [ 28.445627] ? ip_mc_output+0xcb0/0xcb0 [ 28.449579] ? ip_make_skb+0xf2/0x1b0 [ 28.453354] ? ip_fragment.constprop.0+0x200/0x200 [ 28.458268] ip_local_out+0x93/0x170 [ 28.461954] ip_send_skb+0x3a/0xc0 [ 28.465497] udp_send_skb+0x601/0xb70 [ 28.469275] udp_sendmsg+0x15a1/0x1c80 [ 28.473136] ? ip_do_fragment+0x1fb0/0x1fb0 [ 28.477430] ? udp_seq_next+0xa0/0xa0 [ 28.481204] ? unwind_get_return_address+0x51/0x90 [ 28.486106] ? entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 28.491442] ? static_obj+0x50/0x50 [ 28.495040] ? __lock_acquire+0x5fc/0x3f20 [ 28.499246] ? trace_hardirqs_on+0x10/0x10 [ 28.503457] udpv6_sendmsg+0x12ea/0x2560 [ 28.507495] ? trace_hardirqs_on+0x10/0x10 [ 28.511700] ? trace_hardirqs_on+0x10/0x10 [ 28.515912] ? udp_v6_push_pending_frames+0x310/0x310 [ 28.521073] ? reacquire_held_locks+0xb5/0x3f0 [ 28.525625] ? release_sock+0x1b/0x1b0 [ 28.529491] ? ip6_datagram_release_cb+0x270/0x470 [ 28.534396] ? inet_autobind+0x11d/0x180 [ 28.538429] ? lock_downgrade+0x740/0x740 [ 28.542548] ? __local_bh_enable_ip+0xc1/0x170 [ 28.547099] ? trace_hardirqs_on_caller+0x3a8/0x580 [ 28.552182] ? inet_autobind+0x11d/0x180 [ 28.556222] inet_sendmsg+0x11a/0x4e0 [ 28.560001] ? security_socket_sendmsg+0x83/0xb0 [ 28.564729] ? inet_recvmsg+0x4d0/0x4d0 [ 28.568676] sock_sendmsg+0xb5/0x100 [ 28.572361] ___sys_sendmsg+0x326/0x800 [ 28.576306] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 28.581032] ? nlmsg_notify+0x1b0/0x1b0 [ 28.584975] ? kernel_recvmsg+0x210/0x210 [ 28.589098] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 28.594518] ? ___sys_sendmsg+0x423/0x800 [ 28.598640] ? rcu_read_lock_sched_held+0x16c/0x1d0 [ 28.603628] ? kfree+0x1f0/0x250 [ 28.606984] ? ___sys_sendmsg+0x428/0x800 [ 28.611108] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 28.615835] ? trace_hardirqs_on+0x10/0x10 [ 28.620043] ? lock_acquire+0x170/0x3f0 [ 28.623987] ? lock_downgrade+0x740/0x740 [ 28.628105] ? __fdget+0x167/0x1f0 [ 28.631628] ? sockfd_lookup_light+0xb2/0x160 [ 28.636093] __sys_sendmmsg+0x129/0x330 [ 28.640041] ? SyS_sendmsg+0x40/0x40 [ 28.643728] ? __might_fault+0x177/0x1b0 [ 28.647761] ? sockfd_lookup_light+0xb2/0x160 [ 28.652242] ? __sys_sendmsg+0xb6/0x120 [ 28.656185] ? SyS_shutdown+0x160/0x160 [ 28.660136] ? up_read+0x17/0x30 [ 28.663475] SyS_sendmmsg+0x2f/0x50 [ 28.667072] ? __sys_sendmmsg+0x330/0x330 [ 28.671191] do_syscall_64+0x1d5/0x640 [ 28.675051] entry_SYSCALL_64_after_hwframe+0x5e/0xd3 [ 28.680211] RIP: 0033:0x7fb08bbac149 [ 28.683893] RSP: 002b:00007ffe6a52b878 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 [ 28.691573] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb08bbac149 [ 28.698815] RDX: 0000000000000001 RSI: 00000000200017c0 RDI: 0000000000000003 [ 28.706054] RBP: 0000000000000000 R08: 00007ffe6a52ba18 R09: 00007ffe6a52ba18 [ 28.713297] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb08bb6f9d0 [ 28.720539] R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 [ 28.727782] Code: 8b 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 80 e0 55 88 ff 74 24 10 ff 74 24 20 e8 63 62 e4 ff <0f> 0b e8 d8 58 36 fa 4c 8b 64 24 18 e8 ce 04 60 fa 48 c7 c1 a0 [ 28.746841] RIP: skb_panic+0x172/0x174 RSP: ffff8880962aee78 [ 28.752674] ---[ end trace 40c377f9003b5d5d ]--- [ 28.757413] Kernel panic - not syncing: Fatal exception in interrupt [ 28.764042] Kernel Offset: disabled [ 28.767647] Rebooting in 86400 seconds..