GHSA-CFJG-WWX3-VGP6

Vulnerability from github – Published: 2025-10-14 21:30 – Updated: 2025-10-14 21:30
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

udmabuf: validate ubuf->pagecount

Syzbot has reported GPF in sg_alloc_append_table_from_pages(). The problem was in ubuf->pages == ZERO_PTR.

ubuf->pagecount is calculated from arguments passed from user-space. If user creates udmabuf with list.size == 0 then ubuf->pagecount will be also equal to zero; it causes kmalloc_array() to return ZERO_PTR.

Fix it by validating ubuf->pagecount before passing it to kmalloc_array().

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2021-47649"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-02-26T06:37:06Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nudmabuf: validate ubuf-\u003epagecount\n\nSyzbot has reported GPF in sg_alloc_append_table_from_pages(). The\nproblem was in ubuf-\u003epages == ZERO_PTR.\n\nubuf-\u003epagecount is calculated from arguments passed from user-space. If\nuser creates udmabuf with list.size == 0 then ubuf-\u003epagecount will be\nalso equal to zero; it causes kmalloc_array() to return ZERO_PTR.\n\nFix it by validating ubuf-\u003epagecount before passing it to\nkmalloc_array().",
  "id": "GHSA-cfjg-wwx3-vgp6",
  "modified": "2025-10-14T21:30:25Z",
  "published": "2025-10-14T21:30:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47649"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2b6dd600dd72573c23ea180b5b0b2f1813405882"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5d50f851dd307c07ca5591297093f19967c834a9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/811b667cefbea9cb7511a874b169d6a92907137e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9e9b4a269f84d3230f2af84ff42322db676440d9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a3728d32fc61eb0fe283cb8ff60b2c8f751e2202"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b267a8118c2b171bf7d67b90ed64154eeab9fae0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}



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