skb linear:   00000110: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
skb linear:   00000120: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
------------[ cut here ]------------
offset+2 (40565) > skb_headlen() (1651)
WARNING: CPU: 0 PID: 7776 at net/core/dev.c:3314 skb_checksum_help+0x6b2/0x740 net/core/dev.c:3313
Modules linked in:
CPU: 0 PID: 7776 Comm: syz-executor.1 Not tainted 6.1.89-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:skb_checksum_help+0x6b2/0x740 net/core/dev.c:3313
Code: ff df 48 8b 4c 24 18 0f b6 04 01 84 c0 0f 85 83 00 00 00 48 8b 04 24 2b 18 48 c7 c7 a0 0a e1 8b 4c 89 fe 89 da e8 7e 3c d2 f8 <0f> 0b bb ea ff ff ff e9 cd fc ff ff 44 89 e9 80 e1 07 80 c1 03 38
RSP: 0018:ffffc90003ec6ee8 EFLAGS: 00010246
RAX: 1a89ac34637caf00 RBX: 0000000000000673 RCX: 0000000000040000
RDX: ffffc900151c1000 RSI: 000000000003b7c1 RDI: 000000000003b7c2
RBP: dffffc0000000000 R08: ffffffff81528eae R09: fffff520007d8d3d
R10: 0000000000000000 R11: dffffc0000000001 R12: 000000000000d56e
R13: 0000000000009e73 R14: ffff888059e1ac80 R15: 0000000000009e75
FS:  00007fcdee9406c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000e000 CR3: 000000001f02c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ip_do_fragment+0x209/0x1b20 net/ipv4/ip_output.c:774
 ip_finish_output_gso net/ipv4/ip_output.c:279 [inline]
 __ip_finish_output+0x2bd/0x4b0 net/ipv4/ip_output.c:301
 iptunnel_xmit+0x513/0x920 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x22e4/0x2cc0 net/ipv4/ip_tunnel.c:840
 __gre_xmit net/ipv4/ip_gre.c:474 [inline]
 ipgre_xmit+0x866/0xc40 net/ipv4/ip_gre.c:669
 __netdev_start_xmit include/linux/netdevice.h:4853 [inline]
 netdev_start_xmit include/linux/netdevice.h:4867 [inline]
 xmit_one net/core/dev.c:3627 [inline]
 dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3643
 __dev_queue_xmit+0x1bb1/0x3cf0 net/core/dev.c:4293
 packet_snd net/packet/af_packet.c:3077 [inline]
 packet_sendmsg+0x4775/0x61a0 net/packet/af_packet.c:3108
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2514
 ___sys_sendmsg net/socket.c:2568 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2597
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcdedc7dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcdee9400c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fcdeddabf80 RCX: 00007fcdedc7dea9
RDX: 0000000000000000 RSI: 0000000020002ac0 RDI: 0000000000000003
RBP: 00007fcdedcca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fcdeddabf80 R15: 00007fff18adc0f8
 </TASK>