syzbot

netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
------------[ cut here ]------------
WARNING: CPU: 1 PID: 3499 at net/core/dev.c:3249 skb_checksum_help+0x3c3/0x560
Modules linked in:
CPU: 1 PID: 3499 Comm: syz-executor330 Not tainted 5.15.115-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:skb_checksum_help+0x3c3/0x560 net/core/dev.c:3249
Code: ff eb e3 e8 0f 7b 4d f9 4c 89 ff e8 b7 01 00 00 bb ea ff ff ff eb cf e8 fb 7a 4d f9 0f 0b bb ea ff ff ff eb c1 e8 ed 7a 4d f9 <0f> 0b bb ea ff ff ff eb b3 44 89 e1 80 e1 07 fe c1 38 c1 0f 8c 5f
RSP: 0018:ffffc90002fbeee8 EFLAGS: 00010293
RAX: ffffffff88327e63 RBX: 00000000000006aa RCX: ffff888013991dc0
RDX: 0000000000000000 RSI: 0000000000000688 RDI: 00000000000006aa
RBP: 0000000000000688 R08: ffffffff88327d52 R09: fffff520005f7dce
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff888019d632f0 R14: 1ffff110033ac660 R15: ffff888019d63280
FS:  0000555556c63300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001000 CR3: 000000001e710000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ip_do_fragment+0x1cf/0x1f10 net/ipv4/ip_output.c:774
 ip_finish_output_gso net/ipv4/ip_output.c:279 [inline]
 __ip_finish_output+0x2bd/0x4a0 net/ipv4/ip_output.c:301
 iptunnel_xmit+0x50c/0x960 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x1c55/0x24a0 net/ipv4/ip_tunnel.c:810
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0x756/0xa60 net/ipv4/ip_gre.c:661
 __netdev_start_xmit include/linux/netdevice.h:5019 [inline]
 netdev_start_xmit include/linux/netdevice.h:5033 [inline]
 xmit_one net/core/dev.c:3594 [inline]
 dev_hard_start_xmit+0x298/0x7a0 net/core/dev.c:3610
 __dev_queue_xmit+0x1cee/0x3230 net/core/dev.c:4225
 packet_snd net/packet/af_packet.c:3035 [inline]
 packet_sendmsg+0x4478/0x5e70 net/packet/af_packet.c:3066
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2412
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2466
 __sys_sendmsg net/socket.c:2495 [inline]
 __do_sys_sendmsg net/socket.c:2504 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2502
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f2d0d57b569
Code: 28 c3 e8 4a 15 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd20c74dc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffd20c74dd8 RCX: 00007f2d0d57b569
RDX: 0000000000000000 RSI: 0000000020002ac0 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 00007ffd20c74de0
R13: 00007ffd20c74e00 R14: 0000000000000000 R15: 0000000000000000
 </TASK>