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 00 00 00 00 00 00 00 00 00 00 00 00 skb frag: 000000c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 skb frag: 000000d0: 00 00 00 00 00 00 00 00 00 00 00 00 ------------[ cut here ]------------ offset (604) >= skb_headlen() (84) WARNING: CPU: 1 PID: 11281 at net/core/dev.c:3294 skb_checksum_help+0x527/0x740 net/core/dev.c:3294 Modules linked in: CPU: 1 PID: 11281 Comm: syz-executor.0 Not tainted 6.7.0-rc6-syzkaller-00022-g55cb5f43689d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 RIP: 0010:skb_checksum_help+0x527/0x740 net/core/dev.c:3294 Code: 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 00 02 00 00 44 89 e2 2b 53 74 44 89 ee 48 c7 c7 a0 4e e9 8b e8 ca 53 dd f8 90 <0f> 0b 90 90 e9 42 ff ff ff e8 0b 0f 17 f9 44 0f b6 25 a4 f0 92 06 RSP: 0018:ffffc90015377338 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88801f719780 RCX: ffffc90009501000 RDX: 0000000000040000 RSI: ffffffff814db526 RDI: 0000000000000001 RBP: ffff88801f7197f4 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 000000000000045c R13: 000000000000025c R14: ffff88801f7197f0 R15: 00000000000002e8 FS: 00007f7c68b276c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000f000 CR3: 000000007948a000 CR4: 0000000000350ef0 Call Trace: ip_do_fragment+0xa1b/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+0x49c/0x650 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:451 [inline] ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:129 iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82 ipip6_tunnel_xmit net/ipv6/sit.c:1034 [inline] sit_tunnel_xmit+0xed2/0x28f0 net/ipv6/sit.c:1076 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3545 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3561 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4346 dev_queue_xmit include/linux/netdevice.h:3134 [inline] packet_xmit+0x257/0x380 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3087 [inline] packet_sendmsg+0x24c6/0x5220 net/packet/af_packet.c:3119 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2190 __do_sys_sendto net/socket.c:2202 [inline] __se_sys_sendto net/socket.c:2198 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2198 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f7c67e7cbe9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7c68b270c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f7c67f9bf80 RCX: 00007f7c67e7cbe9 RDX: 000000000000fc13 RSI: 0000000020000280 RDI: 0000000000000006 RBP: 00007f7c67ec847a R08: 0000000000000000 R09: 000000000000002f R10: 0000000000000800 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7c67f9bf80 R15: 00007fff74107d38