)]}'
{
  "commit": "a80c9d945aef55b23b54838334345f20251dad83",
  "tree": "e59420d3b63c89ac79bbca2b8de9aec166dc910c",
  "parents": [
    "a74c7a58ca2ca1cbb93f4c01421cf24b8642b962"
  ],
  "author": {
    "name": "Xin Long",
    "email": "lucien.xin@gmail.com",
    "time": "Tue Jan 13 12:10:26 2026 -0500"
  },
  "committer": {
    "name": "Jakub Kicinski",
    "email": "kuba@kernel.org",
    "time": "Sat Jan 17 15:10:34 2026 -0800"
  },
  "message": "sctp: move SCTP_CMD_ASSOC_SHKEY right after SCTP_CMD_PEER_INIT\n\nA null-ptr-deref was reported in the SCTP transmit path when SCTP-AUTH key\ninitialization fails:\n\n  \u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\n  KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]\n  CPU: 0 PID: 16 Comm: ksoftirqd/0 Tainted: G W 6.6.0 #2\n  RIP: 0010:sctp_packet_bundle_auth net/sctp/output.c:264 [inline]\n  RIP: 0010:sctp_packet_append_chunk+0xb36/0x1260 net/sctp/output.c:401\n  Call Trace:\n\n  sctp_packet_transmit_chunk+0x31/0x250 net/sctp/output.c:189\n  sctp_outq_flush_data+0xa29/0x26d0 net/sctp/outqueue.c:1111\n  sctp_outq_flush+0xc80/0x1240 net/sctp/outqueue.c:1217\n  sctp_cmd_interpreter.isra.0+0x19a5/0x62c0 net/sctp/sm_sideeffect.c:1787\n  sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]\n  sctp_do_sm+0x1a3/0x670 net/sctp/sm_sideeffect.c:1169\n  sctp_assoc_bh_rcv+0x33e/0x640 net/sctp/associola.c:1052\n  sctp_inq_push+0x1dd/0x280 net/sctp/inqueue.c:88\n  sctp_rcv+0x11ae/0x3100 net/sctp/input.c:243\n  sctp6_rcv+0x3d/0x60 net/sctp/ipv6.c:1127\n\nThe issue is triggered when sctp_auth_asoc_init_active_key() fails in\nsctp_sf_do_5_1C_ack() while processing an INIT_ACK. In this case, the\ncommand sequence is currently:\n\n- SCTP_CMD_PEER_INIT\n- SCTP_CMD_TIMER_STOP (T1_INIT)\n- SCTP_CMD_TIMER_START (T1_COOKIE)\n- SCTP_CMD_NEW_STATE (COOKIE_ECHOED)\n- SCTP_CMD_ASSOC_SHKEY\n- SCTP_CMD_GEN_COOKIE_ECHO\n\nIf SCTP_CMD_ASSOC_SHKEY fails, asoc-\u003eshkey remains NULL, while\nasoc-\u003epeer.auth_capable and asoc-\u003epeer.peer_chunks have already been set by\nSCTP_CMD_PEER_INIT. This allows a DATA chunk with auth \u003d 1 and shkey \u003d NULL\nto be queued by sctp_datamsg_from_user().\n\nSince command interpretation stops on failure, no COOKIE_ECHO should been\nsent via SCTP_CMD_GEN_COOKIE_ECHO. However, the T1_COOKIE timer has already\nbeen started, and it may enqueue a COOKIE_ECHO into the outqueue later. As\na result, the DATA chunk can be transmitted together with the COOKIE_ECHO\nin sctp_outq_flush_data(), leading to the observed issue.\n\nSimilar to the other places where it calls sctp_auth_asoc_init_active_key()\nright after sctp_process_init(), this patch moves the SCTP_CMD_ASSOC_SHKEY\nimmediately after SCTP_CMD_PEER_INIT, before stopping T1_INIT and starting\nT1_COOKIE. This ensures that if shared key generation fails, authenticated\nDATA cannot be sent. It also allows the T1_INIT timer to retransmit INIT,\ngiving the client another chance to process INIT_ACK and retry key setup.\n\nFixes: 730fc3d05cd4 (\"[SCTP]: Implete SCTP-AUTH parameter processing\")\nReported-by: Zhen Chen \u003cchenzhen126@huawei.com\u003e\nTested-by: Zhen Chen \u003cchenzhen126@huawei.com\u003e\nSigned-off-by: Xin Long \u003clucien.xin@gmail.com\u003e\nLink: https://patch.msgid.link/44881224b375aa8853f5e19b4055a1a56d895813.1768324226.git.lucien.xin@gmail.com\nSigned-off-by: Jakub Kicinski \u003ckuba@kernel.org\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "3755ba079d077c347b548c63998f60bcae786a49",
      "old_mode": 33188,
      "old_path": "net/sctp/sm_statefuns.c",
      "new_id": "7b823d759141917ba6e55b398ae45c46b9bc10b1",
      "new_mode": 33188,
      "new_path": "net/sctp/sm_statefuns.c"
    }
  ]
}