IPVS: ftp: loaded support on port[0] = 21 skbuff: skb_under_panic: text:ffffffff8624fe9f len:48 put:8 head:ffff8880b4901c80 data:ffff8880b4901c7c tail:0x2c end:0xc0 dev:sit1 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:104! invalid opcode: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 8006 Comm: syz-executor280 Not tainted 4.14.282-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880b351a480 task.stack: ffff888097940000 RIP: 0010:skb_panic+0x172/0x174 net/core/skbuff.c:104 RSP: 0018:ffff888097946e58 EFLAGS: 00010282 RAX: 0000000000000083 RBX: ffff88809a87d000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff878bc600 RDI: ffffed1012f28dc1 RBP: ffffffff8855b660 R08: 0000000000000083 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8624fe9f R13: 0000000000000008 R14: ffff8880b35129c0 R15: 00000000000000c0 FS: 0000555556079300(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000009ae14000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_under_panic net/core/skbuff.c:114 [inline] skb_push.cold+0x24/0x24 net/core/skbuff.c:1727 fou_build_udp+0x2f/0x360 net/ipv4/fou.c:960 gue_build_header+0xd1/0x110 net/ipv4/fou.c:1003 ip_tunnel_encap include/net/ip_tunnels.h:342 [inline] ip_tunnel_xmit+0x50e/0x33e0 net/ipv4/ip_tunnel.c:731 sit_tunnel_xmit__ net/ipv6/sit.c:1006 [inline] sit_tunnel_xmit+0x1ab/0x2130 net/ipv6/sit.c:1019 __netdev_start_xmit include/linux/netdevice.h:4054 [inline] netdev_start_xmit include/linux/netdevice.h:4063 [inline] xmit_one net/core/dev.c:3005 [inline] dev_hard_start_xmit+0x188/0x890 net/core/dev.c:3021 __dev_queue_xmit+0x1d7f/0x2480 net/core/dev.c:3521 neigh_output include/net/neighbour.h:500 [inline] ip_finish_output2+0xba6/0x1340 net/ipv4/ip_output.c:237 ip_finish_output+0x37c/0xc50 net/ipv4/ip_output.c:325 NF_HOOK_COND include/linux/netfilter.h:239 [inline] ip_mc_output+0x220/0xcb0 net/ipv4/ip_output.c:398 dst_output include/net/dst.h:470 [inline] ip_local_out+0x93/0x170 net/ipv4/ip_output.c:125 ip_send_skb+0x3a/0xc0 net/ipv4/ip_output.c:1431 udp_send_skb+0x601/0xb70 net/ipv4/udp.c:833 udp_sendmsg+0x15a1/0x1c80 net/ipv4/udp.c:1057 udpv6_sendmsg+0x12ea/0x2560 net/ipv6/udp.c:1193 inet_sendmsg+0x11a/0x4e0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x326/0x800 net/socket.c:2062 __sys_sendmmsg+0x129/0x330 net/socket.c:2152 SYSC_sendmmsg net/socket.c:2183 [inline] SyS_sendmmsg+0x2f/0x50 net/socket.c:2178 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f6d8d543499 RSP: 002b:00007ffd28fa4908 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f6d8d543499 RDX: 0000000000000001 RSI: 00000000200017c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 000000008d5b0e40 R09: 000000008d5b0e40 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000693b R13: 00007ffd28fa4930 R14: 00007ffd28fa4920 R15: 00007ffd28fa4914 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 40 af 55 88 ff 74 24 10 ff 74 24 20 e8 5a 6b e4 ff <0f> 0b e8 ab bf 36 fa 4c 8b 64 24 18 e8 81 61 60 fa 48 c7 c1 60 RIP: skb_panic+0x172/0x174 net/core/skbuff.c:104 RSP: ffff888097946e58 ---[ end trace b47109b5818d3023 ]---