skb linear:   000000c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
skb linear:   000000d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
skb linear:   000000e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
skb linear:   000000f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
skb linear:   00000100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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 (24217) > skb_headlen() (10637)
WARNING: CPU: 0 PID: 20882 at net/core/dev.c:3333 skb_checksum_help+0x5f1/0x750 net/core/dev.c:3333
Modules linked in:
CPU: 0 PID: 20882 Comm: syz.1.2717 Not tainted 6.10.0-rc7-syzkaller-00256-gd0d0cd380055 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:skb_checksum_help+0x5f1/0x750 net/core/dev.c:3333
Code: 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 52 01 00 00 44 89 e2 2b 53 74 4c 89 ee 48 c7 c7 40 e7 51 8c e8 40 b3 8b f8 90 <0f> 0b 90 90 e9 87 fe ff ff e8 51 25 26 f9 e9 3c fa ff ff e8 77 25
RSP: 0018:ffffc9000378efc8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88802ffdadc0 RCX: ffffc9000de6c000
RDX: 0000000000040000 RSI: ffffffff81514a66 RDI: 0000000000000001
RBP: ffff88802ffdae34 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 000000000000298d
R13: 0000000000005e99 R14: ffff88802ffdae30 R15: 0000000000005e97
FS:  00007fda3a3706c0(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000e000 CR3: 000000005c908000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 ip_do_fragment+0xa1c/0x18b0 net/ipv4/ip_output.c:777
 ip_fragment.constprop.0+0x161/0x230 net/ipv4/ip_output.c:584
 ip_finish_output_gso net/ipv4/ip_output.c:286 [inline]
 __ip_finish_output net/ipv4/ip_output.c:308 [inline]
 __ip_finish_output+0x5af/0x950 net/ipv4/ip_output.c:295
 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_output+0x13b/0x2a0 net/ipv4/ip_output.c:433
 dst_output include/net/dst.h:450 [inline]
 ip_local_out+0x33e/0x4a0 net/ipv4/ip_output.c:129
 iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x1e7c/0x33f0 net/ipv4/ip_tunnel.c:857
 __gre_xmit+0x89d/0xbd0 net/ipv4/ip_gre.c:483
 ipgre_xmit+0x578/0xb30 net/ipv4/ip_gre.c:687
 __netdev_start_xmit include/linux/netdevice.h:4882 [inline]
 netdev_start_xmit include/linux/netdevice.h:4896 [inline]
 xmit_one net/core/dev.c:3578 [inline]
 dev_hard_start_xmit+0x146/0x790 net/core/dev.c:3594
 __dev_queue_xmit+0x7ba/0x4130 net/core/dev.c:4393
 dev_queue_xmit include/linux/netdevice.h:3095 [inline]
 packet_xmit+0x23e/0x360 net/packet/af_packet.c:276
 packet_snd net/packet/af_packet.c:3080 [inline]
 packet_sendmsg+0x24a5/0x51e0 net/packet/af_packet.c:3112
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0xab8/0xc90 net/socket.c:2585
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2639
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2668
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fda39575bd9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fda3a370048 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fda39703f60 RCX: 00007fda39575bd9
RDX: 0000000000000000 RSI: 0000000020002ac0 RDI: 0000000000000003
RBP: 00007fda395e4e60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fda39703f60 R15: 00007ffe596856c8
 </TASK>