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CVE-2026-99151

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix NULL sink dereference in USB4 bandwidth functions allocate_usb4_bandwidth_for_stream() and allocate_usb4_bandwidth() both use ASSERT(stream->sink) before dereferencing stream->sink->link. ASSERT is compiled out in production builds, so a NULL stream->sink causes a NULL pointer dereference. link_set_dpms_off() already guards two earlier accesses to stream->sink with explicit NULL checks, confirming that stream->sink can legitimately be NULL. The subsequent call to deallocate_usb4_bandwidth() had no equivalent guard. Replace the ASSERT() calls with proper NULL checks that return false early, and add a matching stream->sink guard at the call site in link_set_dpms_off() consistent with the surrounding pattern. v2: Keep the existing ASSERT() calls for diagnostics (to report unexpected NULL sink), and add explicit NULL checks that return false before dereferencing stream->sink. Also add a matching stream->sink guard at the deallocation call site in link_set_dpms_off(). (Alex) (cherry picked from commit 98029a0ce61feb52c563f65349dd9b25f672e355)

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-10-28 11:17:35.207000
Last modified
2026-10-28 11:17:35.207000
View original CVE JSON
{
  "id": "CVE-2026-99151",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-28T11:17:35.207",
  "lastModified": "2026-10-28T11:17:35.207",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: Fix NULL sink dereference in USB4 bandwidth functions\n\nallocate_usb4_bandwidth_for_stream() and allocate_usb4_bandwidth() both\nuse ASSERT(stream->sink) before dereferencing stream->sink->link. ASSERT\nis compiled out in production builds, so a NULL stream->sink causes a\nNULL pointer dereference.\n\nlink_set_dpms_off() already guards two earlier accesses to stream->sink\nwith explicit NULL checks, confirming that stream->sink can legitimately\nbe NULL. The subsequent call to deallocate_usb4_bandwidth() had no\nequivalent guard.\n\nReplace the ASSERT() calls with proper NULL checks that return false\nearly, and add a matching stream->sink guard at the call site in\nlink_set_dpms_off() consistent with the surrounding pattern.\n\nv2: Keep the existing ASSERT() calls for diagnostics (to report\n    unexpected NULL sink), and add explicit NULL checks that return false\n    before dereferencing stream->sink. Also add a matching stream->sink\n    guard at the deallocation call site in link_set_dpms_off(). (Alex)\n\n(cherry picked from commit 98029a0ce61feb52c563f65349dd9b25f672e355)"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/amd/display/dc/link/link_dpms.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "0b1eebd359685dd681f6e0df5540a5bb985a27bf",
              "lessThan": "4c8b5e5b9776ad08138d79b14238c5742b32911b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8fa813b7fd1eccbed13e126166cf764f1f11a7d3",
              "lessThan": "55a67aa89342545b89f469dea6f29bfb6fac6f3d",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/amd/display/dc/link/link_dpms.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.2.9",
              "lessThan": "7.2.13",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/4c8b5e5b9776ad08138d79b14238c5742b32911b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/55a67aa89342545b89f469dea6f29bfb6fac6f3d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}