)]}'
{
  "commit": "4ab2cd906e4e1a19ddbda6eb532851b0e9cda110",
  "tree": "2bbc6c5fedc848f6818e82bda20221211834e8b4",
  "parents": [
    "f21e4cc4a6bafadfaa86b118917b5a5f15e75976"
  ],
  "author": {
    "name": "Andrii Melnychenko",
    "email": "a.melnychenko@vyos.io",
    "time": "Fri Jan 02 12:37:21 2026 -0800"
  },
  "committer": {
    "name": "Greg Kroah-Hartman",
    "email": "gregkh@linuxfoundation.org",
    "time": "Thu Jan 08 10:15:00 2026 +0100"
  },
  "message": "netfilter: nft_ct: add seqadj extension for natted connections\n\n[ Upstream commit 90918e3b6404c2a37837b8f11692471b4c512de2 ]\n\nSequence adjustment may be required for FTP traffic with PASV/EPSV modes.\ndue to need to re-write packet payload (IP, port) on the ftp control\nconnection. This can require changes to the TCP length and expected\nseq / ack_seq.\n\nThe easiest way to reproduce this issue is with PASV mode.\nExample ruleset:\ntable inet ftp_nat {\n        ct helper ftp_helper {\n                type \"ftp\" protocol tcp\n                l3proto inet\n        }\n\n        chain prerouting {\n                type filter hook prerouting priority 0; policy accept;\n                tcp dport 21 ct state new ct helper set \"ftp_helper\"\n        }\n}\ntable ip nat {\n        chain prerouting {\n                type nat hook prerouting priority -100; policy accept;\n                tcp dport 21 dnat ip prefix to ip daddr map {\n\t\t\t192.168.100.1 : 192.168.13.2/32 }\n        }\n\n        chain postrouting {\n                type nat hook postrouting priority 100 ; policy accept;\n                tcp sport 21 snat ip prefix to ip saddr map {\n\t\t\t192.168.13.2 : 192.168.100.1/32 }\n        }\n}\n\nNote that the ftp helper gets assigned *after* the dnat setup.\n\nThe inverse (nat after helper assign) is handled by an existing\ncheck in nf_nat_setup_info() and will not show the problem.\n\nTopoloy:\n\n +-------------------+     +----------------------------------+\n | FTP: 192.168.13.2 | \u003c-\u003e | NAT: 192.168.13.3, 192.168.100.1 |\n +-------------------+     +----------------------------------+\n                                      |\n                         +-----------------------+\n                         | Client: 192.168.100.2 |\n                         +-----------------------+\n\nftp nat changes do not work as expected in this case:\nConnected to 192.168.100.1.\n[..]\nftp\u003e epsv\nEPSV/EPRT on IPv4 off.\nftp\u003e ls\n227 Entering passive mode (192,168,100,1,209,129).\n421 Service not available, remote server has closed connection.\n\nKernel logs:\nMissing nfct_seqadj_ext_add() setup call\nWARNING: CPU: 1 PID: 0 at net/netfilter/nf_conntrack_seqadj.c:41\n[..]\n __nf_nat_mangle_tcp_packet+0x100/0x160 [nf_nat]\n nf_nat_ftp+0x142/0x280 [nf_nat_ftp]\n help+0x4d1/0x880 [nf_conntrack_ftp]\n nf_confirm+0x122/0x2e0 [nf_conntrack]\n nf_hook_slow+0x3c/0xb0\n ..\n\nFix this by adding the required extension when a conntrack helper is assigned\nto a connection that has a nat binding.\n\nFixes: 1a64edf54f55 (\"netfilter: nft_ct: add helper set support\")\nSigned-off-by: Andrii Melnychenko \u003ca.melnychenko@vyos.io\u003e\nSigned-off-by: Florian Westphal \u003cfw@strlen.de\u003e\n[Harshit: Clean cherry-pick, apply it to stable-6.12.y]\nSigned-off-by: Harshit Mogalapalli \u003charshit.m.mogalapalli@oracle.com\u003e\nSigned-off-by: Greg Kroah-Hartman \u003cgregkh@linuxfoundation.org\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "a1b373b99f7b84b4636002deaa163b618c71560a",
      "old_mode": 33188,
      "old_path": "net/netfilter/nft_ct.c",
      "new_id": "58a6ad7ed7a4661e95fe9ea2fbfcec1f6840c7bf",
      "new_mode": 33188,
      "new_path": "net/netfilter/nft_ct.c"
    }
  ]
}