{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "f9b94daa542a8d2532f0930f01cd9aec2d19621b"
            },
            {
              "fixed": "6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9"
            },
            {
              "fixed": "50f4a793c4ff24826efb0ac700989a5063cc53df"
            },
            {
              "fixed": "0c7c517827a453128a8f58bfd849546a29813b27"
            },
            {
              "fixed": "8a5f63637890f03177146efddaba5ec7a1b4d61f"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.8.0"
            },
            {
              "fixed": "6.12.109"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.50"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89771.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix subbuf resize race with ring buffer readers\n\ntrace_buffer subbuf_size is read lockless in ring_buffer_read_page() and\nring_buffer_read_start(), while it can simultaneously be resized with\nring_buffer_subbuf_order_set().\n\nInstead of trace_buffer::subbuf_size, use bpage::order in\nring_buffer_read_start() and ring_buffer_read_page().\n\nIn ring_buffer_read_start(), even with resize_disabled, there is still a\npossibility of a race with a buffer modification. Hold the trace_buffer\nmutex to synchronise with any pending ring buffer order modification.\n\ntrace_buffer::subbuf_size is now actually useless, remove it. Also,\ncreate accessors rb_subbuf_capacity() and rb_page_capacity() which\nreturn the actual size available for storing events, while\nrb_subbuf_size() returns the actual subbuf page-size.",
  "id": "CVE-2026-89771",
  "modified": "2026-09-15T03:30:23.368272506Z",
  "published": "2026-09-11T19:47:10.381Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0c7c517827a453128a8f58bfd849546a29813b27"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/50f4a793c4ff24826efb0ac700989a5063cc53df"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6d666f0b8b36c0765cf19fbe6de5a7ba5a73aad9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8a5f63637890f03177146efddaba5ec7a1b4d61f"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89771.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89771"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ring-buffer: Fix subbuf resize race with ring buffer readers"
}