skb frag:     000000a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
skb frag:     000000b0: 00 00 00 00
------------[ cut here ]------------
offset+2 (1321) > skb_headlen() (124)
WARNING: CPU: 0 PID: 5206 at net/core/dev.c:3335 skb_checksum_help+0x5f1/0x750 net/core/dev.c:3335
Modules linked in:
CPU: 0 UID: 0 PID: 5206 Comm: syz-executor406 Not tainted 6.10.0-syzkaller-12097-ge9680017b2dc #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:skb_checksum_help+0x5f1/0x750 net/core/dev.c:3335
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 a0 42 53 8c e8 50 0a 83 f8 90 <0f> 0b 90 90 e9 87 fe ff ff e8 f1 fb 1d f9 e9 3c fa ff ff e8 17 fc
RSP: 0018:ffffc900033c6f10 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff888024443680 RCX: ffffffff814cc4b9
RDX: ffff888029cd8000 RSI: ffffffff814cc4c6 RDI: 0000000000000001
RBP: ffff8880244436f4 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000006f5
R13: 0000000000000529 R14: ffff8880244436f0 R15: 0000000000000527
FS:  0000555585507380(0000) GS:ffff88806b000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001000 CR3: 0000000026314000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ip_do_fragment+0xa1e/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_mc_output+0x1dd/0x6a0 net/ipv4/ip_output.c:420
 dst_output include/net/dst.h:450 [inline]
 dst_output include/net/dst.h:448 [inline]
 ip_local_out+0x286/0x4a0 net/ipv4/ip_output.c:129
 iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x1e82/0x33f0 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:4913 [inline]
 netdev_start_xmit include/linux/netdevice.h:4922 [inline]
 xmit_one net/core/dev.c:3580 [inline]
 dev_hard_start_xmit+0x143/0x790 net/core/dev.c:3596
 __dev_queue_xmit+0x7c7/0x4300 net/core/dev.c:4423
 dev_queue_xmit include/linux/netdevice.h:3105 [inline]
 packet_xmit+0x23e/0x360 net/packet/af_packet.c:276
 packet_snd net/packet/af_packet.c:3145 [inline]
 packet_sendmsg+0x268f/0x53a0 net/packet/af_packet.c:3177
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0xab5/0xc90 net/socket.c:2597
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2680
 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: 0033:0x7f0076867779
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd393e76d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f00768b4468 RCX: 00007f0076867779
RDX: 0000000000000000 RSI: 0000000020002ac0 RDI: 0000000000000003
RBP: 00007f00768b4446 R08: 0000555500000000 R09: 0000555500000000
R10: 0000000000000004 R11: 0000000000000246 R12: 00007f00768b4406
R13: 0000000000000001 R14: 00007ffd393e7720 R15: 0000000000000003
 </TASK>