CVE-2026-99158

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Fix false warning in ring_buffer_map_get_reader() The mmap reader can warn when it catches up with a writer that is still committing events. rb_get_reader_page() returns NULL in this case, but ring_buffer_map_get_reader() treats that result as an error. The initial rb_per_cpu_empty() check filters out an empty buffer, but it does not guarantee that the next reader page has committed data. Writers do not take reader_lock and can advance commit_page before publishing the committed length on the new page. rb_get_reader_page() can swap to that page, catch up with the writer and return NULL. Handle NULL through the existing no-data exit without warning. Remove the caller's reader_page == commit_page check as well, since the reader-page helper already handles that case. The existing metadata update and return path remain in place.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-10-28 11:17:36.050000

Last modified

2026-10-28 11:17:36.050000

View original CVE JSON

{
  "id": "CVE-2026-99158",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-28T11:17:36.050",
  "lastModified": "2026-10-28T11:17:36.050",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix false warning in ring_buffer_map_get_reader()\n\nThe mmap reader can warn when it catches up with a writer that is still\ncommitting events. rb_get_reader_page() returns NULL in this case, but\nring_buffer_map_get_reader() treats that result as an error.\n\nThe initial rb_per_cpu_empty() check filters out an empty buffer, but it\ndoes not guarantee that the next reader page has committed data. Writers\ndo not take reader_lock and can advance commit_page before publishing the\ncommitted length on the new page. rb_get_reader_page() can swap to that\npage, catch up with the writer and return NULL.\n\nHandle NULL through the existing no-data exit without warning. Remove the\ncaller's reader_page == commit_page check as well, since the reader-page\nhelper already handles that case. The existing metadata update and return\npath remain in place."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/trace/ring_buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "117c39200d9d760cbd5944bb89efb7b9c51965aa",
              "lessThan": "029770f5badedc0f0ff85fc45e24785cbbee4a67",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "117c39200d9d760cbd5944bb89efb7b9c51965aa",
              "lessThan": "68e6ab180cfb6dfa79652f41ed7899a6d4cf5438",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "117c39200d9d760cbd5944bb89efb7b9c51965aa",
              "lessThan": "89bab1dba8a0167ef0d819e0f55b6bafa038e87f",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/trace/ring_buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.10",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.10",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.59",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.13",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/029770f5badedc0f0ff85fc45e24785cbbee4a67",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/68e6ab180cfb6dfa79652f41ed7899a6d4cf5438",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/89bab1dba8a0167ef0d819e0f55b6bafa038e87f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}