netfilter-full-cone-nat Kernel Crash (NULL pointer)

System: CentOS 7 4.19.1-1.el7.elrepo.x86_64 iptables: 1.8.2 complied as README

crash after run iptables -t nat -A POSTROUTING -o eth0 -j FULLCONENAT

Crash dmesg

[   54.288781] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
[   54.289554] PGD 0 P4D 0 
[   54.289811] Oops: 0002 [#1] SMP PTI
[   54.290132] CPU: 0 PID: 9300 Comm: sshd Kdump: loaded Tainted: G           O      4.19.1-1.el7.elrepo.x86_64 #1
[   54.291072] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[   54.292194] RIP: 0010:fullconenat_tg+0x132/0x7f0 [xt_FULLCONENAT]
[   54.292767] Code: 51 e1 41 80 fe 11 4c 8b 45 90 4c 8b 4d 88 0f 84 9e 03 00 00 31 c0 c7 85 78 ff ff ff 00 00 00 00 45 31 f6 66 89 45 88 8b 45 98 <89> 04 25 04 00 00 00 49 8b 45 10 48 85 c0 0f 84 e0 02 00 00 48 8b
[   54.294461] RSP: 0018:ffffc90002caf788 EFLAGS: 00010246
[   54.294951] RAX: 0000000000000002 RBX: ffff88003ca3a000 RCX: 0000000000000006
[   54.295603] RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffffa0367ce4
[   54.296252] RBP: ffffc90002caf840 R08: ffffffff823f6580 R09: ffffc90002caf920
[   54.296976] R10: ffff88003b892b20 R11: ffff880035c80000 R12: ffff88003ca3a00a
[   54.297624] R13: ffff88003c654ce8 R14: 0000000000000000 R15: ffff88003b892b40
[   54.298284] FS:  00007f84377c98c0(0000) GS:ffff88003ea00000(0000) knlGS:0000000000000000
[   54.299060] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   54.299582] CR2: 0000000000000004 CR3: 0000000035e5c002 CR4: 00000000003606f0
[   54.300241] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   54.300885] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   54.301546] Call Trace:
[   54.301787]  ? hash_conntrack_raw+0x132/0x170 [nf_conntrack]
[   54.302320]  ipt_do_table+0x2e7/0x630 [ip_tables]
[   54.302755]  ? nf_nat_setup_info+0x93/0x290 [nf_nat]
[   54.303249]  ? ipt_do_table+0x32a/0x630 [ip_tables]
[   54.303703]  ? __nf_nat_alloc_null_binding+0x30/0xb0 [nf_nat]
[   54.304221]  iptable_nat_do_chain+0x1f/0x30 [iptable_nat]
[   54.304729]  nf_nat_inet_fn+0x126/0x240 [nf_nat]
[   54.305151]  nf_nat_ipv4_fn+0x41/0x70 [nf_nat_ipv4]
[   54.305619]  nf_nat_ipv4_out+0x19/0xc0 [nf_nat_ipv4]
[   54.306072]  nf_hook_slow+0x42/0xc0
[   54.306400]  ip_output+0xd0/0xe0
[   54.306721]  ? ip_fragment.constprop.49+0x80/0x80
[   54.307149]  ip_local_out+0x3b/0x50
[   54.307477]  __ip_queue_xmit+0x155/0x3e0
[   54.307852]  ip_queue_xmit+0x10/0x20
[   54.308183]  __tcp_transmit_skb+0x5b4/0xae0
[   54.308588]  tcp_write_xmit+0x257/0xfc0
[   54.308952]  __tcp_push_pending_frames+0x31/0xd0
[   54.310481]  tcp_push+0xdf/0x110
[   54.311853]  tcp_sendmsg_locked+0x9c1/0xe40
[   54.313308]  ? __list_del_entry+0x30/0x30
[   54.314732]  tcp_sendmsg+0x2c/0x50
[   54.316066]  inet_sendmsg+0x37/0xb0
[   54.317410]  sock_sendmsg+0x3e/0x50
[   54.318706]  sock_write_iter+0x85/0xf0
[   54.320065]  __vfs_write+0x10d/0x190
[   54.321343]  vfs_write+0xb2/0x1b0
[   54.322581]  ksys_write+0x55/0xc0
[   54.323849]  __x64_sys_write+0x1a/0x20
[   54.325100]  do_syscall_64+0x60/0x190
[   54.326335]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   54.327658] RIP: 0033:0x7f8434c08cd0
[   54.328809] Code: 73 01 c3 48 8b 0d c0 61 2d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d cd c2 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee cb 01 00 48 89 04 24
[   54.332143] RSP: 002b:00007ffc09d88a78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   54.333693] RAX: ffffffffffffffda RBX: 000055c4c85b9490 RCX: 00007f8434c08cd0
[   54.335202] RDX: 0000000000000030 RSI: 000055c4c8623420 RDI: 0000000000000003
[   54.336646] RBP: 0000000000000030 R08: 0000000000000000 R09: 0000000000000000
[   54.338078] R10: 0000000000000008 R11: 0000000000000246 R12: 00007ffc09d88aff
[   54.339499] R13: 000055c4c82e77a0 R14: 0000000000000003 R15: 0000000000000000
[   54.340913] Modules linked in: iptable_nat nf_nat_ipv4 xt_FULLCONENAT(O) nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c iptable_filter wireguard(O) ip6_udp_tunnel udp_tunnel sb_edac crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel crypto_simd cryptd glue_helper joydev input_leds pcspkr virtio_balloon i2c_piix4 sch_fq ip_tables ext4 mbcache jbd2 virtio_net net_failover failover virtio_console virtio_blk ata_generic pata_acpi cirrus crc32c_intel drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops serio_raw ttm ata_piix virtio_pci virtio_ring virtio drm libata floppy tcp_bbr
[   54.349912] CR2: 0000000000000004