------------[ cut here ]------------ WARNING: CPU: 0 PID: 16753 at net/core/dev.c:3284 skb_checksum_help+0x3d0/0x5b0 Modules linked in: CPU: 0 PID: 16753 Comm: syz-executor.0 Not tainted 6.1.32-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 RIP: 0010:skb_checksum_help+0x3d0/0x5b0 net/core/dev.c:3284 Code: 4c 89 ff e8 02 02 00 00 bb ea ff ff ff eb cf 0f 0b 80 3d c6 48 c4 05 01 0f 85 ac 01 00 00 e8 a7 f8 0e f9 bb ea ff ff ff eb b4 <0f> 0b 80 3d ac 48 c4 05 01 0f 85 9f 01 00 00 e8 8c f8 0e f9 bb ea RSP: 0018:ffffc900032d6f08 EFLAGS: 00010206 RAX: 0000000000000002 RBX: 00000000000006aa RCX: ffff888024bb8000 RDX: ffff8880ad3ef2f4 RSI: 0000000000000688 RDI: 00000000000006aa RBP: 0000000000000688 R08: ffffffff887adbb5 R09: fffff5200065add2 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff11015a7de60 R13: ffff8880ad3ef2f0 R14: dffffc0000000000 R15: ffff8880ad3ef280 FS: 00007f9a7f94d700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001000 CR3: 00000000785c8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: 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+0x50c/0x930 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x2296/0x2c70 net/ipv4/ip_tunnel.c:813 __gre_xmit net/ipv4/ip_gre.c:469 [inline] ipgre_xmit+0x759/0xa60 net/ipv4/ip_gre.c:661 __netdev_start_xmit include/linux/netdevice.h:4850 [inline] netdev_start_xmit include/linux/netdevice.h:4864 [inline] xmit_one net/core/dev.c:3595 [inline] dev_hard_start_xmit+0x261/0x8c0 net/core/dev.c:3611 __dev_queue_xmit+0x1b97/0x3c90 net/core/dev.c:4261 packet_snd net/packet/af_packet.c:3073 [inline] packet_sendmsg+0x4750/0x6170 net/packet/af_packet.c:3104 sock_sendmsg_nosec net/socket.c:716 [inline] sock_sendmsg net/socket.c:736 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482 ___sys_sendmsg net/socket.c:2536 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2565 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+0x63/0xcd RIP: 0033:0x7f9a7ec8c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9a7f94d168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9a7edabf80 RCX: 00007f9a7ec8c169 RDX: 0000000000000000 RSI: 0000000020002ac0 RDI: 0000000000000003 RBP: 00007f9a7ece7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff41a670ef R14: 00007f9a7f94d300 R15: 0000000000022000