{"id":"CVE-2026-99151","title":"drm/amd/display: Fix NULL sink dereference in USB4 bandwidth functions","summary":"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)…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 0b1eebd359685dd681f6e0df5540a5bb985a27bf < 4c8b5e5b9776ad08138d79b14238c5742b32911b","Linux >= 8fa813b7fd1eccbed13e126166cf764f1f11a7d3 < 55a67aa89342545b89f469dea6f29bfb6fac6f3d","Linux >= 7.2.9 < 7.2.13"],"published":"2026-10-28","updated":"2026-10-28","sourceUpdated":"2026-10-28T10:35:06.866Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99151","references":[{"url":"https://git.kernel.org/stable/c/4c8b5e5b9776ad08138d79b14238c5742b32911b"},{"url":"https://git.kernel.org/stable/c/55a67aa89342545b89f469dea6f29bfb6fac6f3d"}],"tags":["cve.org"],"ingestedAt":"2026-10-28T11:09:40.416Z","slug":"CVE-2026-99151","body":"## Overview\n\nIn 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)\n\n## Affected\n\n- `Linux >= 0b1eebd359685dd681f6e0df5540a5bb985a27bf < 4c8b5e5b9776ad08138d79b14238c5742b32911b`\n- `Linux >= 8fa813b7fd1eccbed13e126166cf764f1f11a7d3 < 55a67aa89342545b89f469dea6f29bfb6fac6f3d`\n- `Linux >= 7.2.9 < 7.2.13`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}