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 (40565) > skb_headlen() (1651) WARNING: CPU: 0 PID: 5088 at net/core/dev.c:3287 skb_checksum_help+0x68f/0x730 net/core/dev.c:3286 Modules linked in: CPU: 0 PID: 5088 Comm: syz-executor380 Not tainted 6.9.0-rc6-syzkaller-00042-g50dffbf77180 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:skb_checksum_help+0x68f/0x730 net/core/dev.c:3286 Code: 48 8b 4c 24 10 0f b6 04 01 84 c0 0f 85 89 00 00 00 48 8b 44 24 08 2b 18 48 c7 c7 60 53 c1 8c 4c 89 f6 89 da e8 b2 25 06 f8 90 <0f> 0b 90 90 bb ea ff ff ff e9 cf fc ff ff 48 8b 0c 24 80 e1 07 80 RSP: 0018:ffffc900035cee48 EFLAGS: 00010246 RAX: 91db37ef144f2800 RBX: 0000000000000673 RCX: ffff88802b820000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff81589072 R09: 1ffff1101728519a R10: dffffc0000000000 R11: ffffed101728519b R12: 1ffff11003f0059e R13: 0000000000009e73 R14: 0000000000009e75 R15: ffff88801f802c80 FS: 000055557eb64380(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000e000 CR3: 000000007709e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip_do_fragment+0x21b/0x1b60 net/ipv4/ip_output.c:777 ip_finish_output_gso net/ipv4/ip_output.c:286 [inline] __ip_finish_output+0x290/0x400 net/ipv4/ip_output.c:308 iptunnel_xmit+0x540/0x9b0 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x20ef/0x2940 net/ipv4/ip_tunnel.c:857 __gre_xmit net/ipv4/ip_gre.c:474 [inline] ipgre_xmit+0x854/0xc30 net/ipv4/ip_gre.c:670 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3547 __dev_queue_xmit+0x1ad1/0x3ca0 net/core/dev.c:4341 packet_snd net/packet/af_packet.c:3081 [inline] packet_sendmsg+0x46a9/0x6130 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f12120cc499 Code: 48 83 c4 28 c3 e8 d7 19 00 00 0f 1f 80 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffdef0ead68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f1212119390 RCX: 00007f12120cc499 RDX: 0000000000000000 RSI: 0000000020002ac0 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000555500000000 R09: 0000555500000000 R10: 0000000000000004 R11: 0000000000000246 R12: 00007ffdef0eadb0 R13: 00007ffdef0ead80 R14: 0000000000000001 R15: 00007ffdef0eadb0