{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2024-46844",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2024-46844"
  ],
  "published": "2024-09-27T12:40:05Z",
  "summary": "um: line: always fill *error_out in setup_one_line()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\num: line: always fill *error_out in setup_one_line()\n\nThe pointer isn't initialized by callers, but I have\nencountered cases where it's still printed; initialize\nit in all possible cases in setup_one_line().",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.110",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2024-46844"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/3bedb7ce080690d0d6172db790790c1219bcbdd5"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/96301fdc2d533a196197c055af875fe33d47ef84"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c8944d449fda9f58c03bd99649b2df09948fc874"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/43f782c27907f306c664b6614fd6f264ac32cce6"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/289979d64573f43df1d0e6bc6435de63a0d69cdf"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ec5b47a370177d79ae7773858042c107e21f8ecc"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fc843d3837ebcb1c16d3768ef3eb55e25d5331f2"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/824ac4a5edd3f7494ab1996826c4f47f8ef0f63d"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-05T11:52:36Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.1,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The only ways to reach `setup_one_line()` are the UML kernel command line at boot (`con0=none`/`ssl0=none` via `console_chan_setup`/`ssl_chan_setup`) and the `config`/`remove` commands on the mconsole AF_UNIX datagram socket in `~/.uml/<umid>/mconsole`; no path is driven by received network packets or by an adjacent link peer.\nAC:L - The failure is fully deterministic \u2014 two consecutive `remove con0` mconsole commands drive `line->valid` to 0 and then hit the `\"none\"` + `!valid` branch that leaves `*error_out` untouched, with no race, timing window, or memory-layout precondition.\nPR:L - There is no `capable()`, credential, or authentication check anywhere on the `mconsole_remove \u2192 con_remove/ssl_remove \u2192 line_remove \u2192 setup_one_line` path, and the mconsole protocol authenticates nothing; any ordinary local account able to write to the socket (created under a `mkdir(uml_dir, 0777)` tree) can issue the command, and it is not real root or an init-namespace capability.\nUI:N - The fault fires synchronously as a direct consequence of the attacker's own `remove`/`config` command or boot-line setting; no victim has to open a device, mount anything, or take any other action.\nS:U - The oops and the leaked data are confined to the UML kernel instance that owns the vulnerable code; no VM-to-host, IOMMU, or sandbox authority boundary is crossed by the dereference itself.\nC:H - The `stdio_init()`/`ssl_init()` callers pass a genuinely uninitialized stack `char *error` that `setup_one_line()` leaves untouched, and `printk(\"%s\", error)` then dereferences that wild pointer, copying an unbounded NUL-terminated run of UML kernel memory into the kernel log where any unprivileged user can harvest it with `dmesg` \u2014 an uncontrolled read of arbitrary kernel memory rather than a small bounded leak.\nI:N - Both the `strlen(NULL)` in `mconsole_reply()` and the `%s` formatting are pure reads; no kernel object is written, freed, or corrupted, and the line state left behind by the failed `remove` is not a security-relevant modification.\nA:H - `mconsole_remove()` passes the still-NULL `err_msg` straight into `mconsole_reply() \u2192 strlen(NULL)`, and the boot-time callers dereference a wild stack pointer inside `printk`, either of which produces a kernel oops/SIGSEGV that panics the UML instance."
    }
  }
}