{
  "cveId": "CVE-2025-21630",
  "url": "https://patchblox.com/security/cve/CVE-2025-21630",
  "summary": "CVE-2025-21630 is fixed in linux on 1 platform by CVE-2025-21630 (version 6.12.9-1), released January 15, 2025. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/net: always initialize kmsg-\u003Emsg.msg_in...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/net: always initialize kmsg-\u003Emsg.msg_inq upfront\n\nsyzbot reports that -\u003Emsg_inq may get used uinitialized from the\nfollowing path:\n\nBUG: KMSAN: uninit-value in io_recv_buf_select io_uring/net.c:1094 [inline]\nBUG: KMSAN: uninit-value in io_recv\u002B0x930/0x1f90 io_uring/net.c:1158\n io_recv_buf_select io_uring/net.c:1094 [inline]\n io_recv\u002B0x930/0x1f90 io_uring/net.c:1158\n io_issue_sqe\u002B0x420/0x2130 io_uring/io_uring.c:1740\n io_queue_sqe io_uring/io_uring.c:1950 [inline]\n io_req_task_submit\u002B0xfa/0x1d0 io_uring/io_uring.c:1374\n io_handle_tw_list\u002B0x55f/0x5c0 io_uring/io_uring.c:1057\n tctx_task_work_run\u002B0x109/0x3e0 io_uring/io_uring.c:1121\n tctx_task_work\u002B0x6d/0xc0 io_uring/io_uring.c:1139\n task_work_run\u002B0x268/0x310 kernel/task_work.c:239\n io_run_task_work\u002B0x43a/0x4a0 io_uring/io_uring.h:343\n io_cqring_wait io_uring/io_uring.c:2527 [inline]\n __do_sys_io_uring_enter io_uring/io_uring.c:3439 [inline]\n __se_sys_io_uring_enter\u002B0x204f/0x4ce0 io_uring/io_uring.c:3330\n __x64_sys_io_uring_enter\u002B0x11f/0x1a0 io_uring/io_uring.c:3330\n x64_sys_call\u002B0xce5/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:427\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64\u002B0xcd/0x1e0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe\u002B0x77/0x7f\n\nand it is correct, as it\u0027s never initialized upfront. Hence the first\nsubmission can end up using it uninitialized, if the recv wasn\u0027t\nsuccessful and the networking stack didn\u0027t honor -\u003Emsg_get_inq being set\nand filling in the output value of -\u003Emsg_inq as requested.\n\nSet it to 0 upfront when it\u0027s allocated, just to silence this KMSAN\nwarning. There\u0027s no side effect of using it uninitialized, it\u0027ll just\npotentially cause the next receive to use a recv value hint that\u0027s not\naccurate.",
  "published": "2025-01-15T13:15:15Z",
  "severity": "",
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.9-1",
      "fix": "CVE-2025-21630",
      "url": "https://patchblox.com/security/fix/linux/cve-2025-21630",
      "released": "2025-01-15T13:15:15Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}