drm/vmwgfx: enforce cursor size limits for MOB cursors

{
  "id": "287d51a0de2fb821783afbabe5c6f4b3a778a5f2ad425fe16e6a80a71ce5131f",
  "url": "https://osv.dev/vulnerability/CVE-2026-80701",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "drm/vmwgfx: enforce cursor size limits for MOB cursors",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: enforce cursor size limits for MOB cursors vmw_cursor_plane_atomic_check() bounds cursor width and height only on the legacy update path; the SVGA_CAP2_CURSOR_MOB path -- the default on modern hosts -- accepts any size. When the requested size exceeds SVGA_REG_CURSOR_MAX_DIMENSION or SVGA_REG_MOB_MAX_SIZE, vmw_cursor_mob_get() returns -EINVAL and leaves vps->cursor.mob NULL. Its return value is then discarded in vmw_cursor_plane_prepare_fb(), so the subsequent vmw_cursor_update_mob() calls vmw_bo_map_and_cache(NULL) and oopses inside vmw_bo_map_and_cache_size() on the tbo.base.size load. Reachable from any DRM master via DRM_IOCTL_MODE_CURSOR2 with a sufficiently large width or height (e.g. cursor_max_dim + 1). Reject oversized cursors in atomic_check for both MOB-backed cursor update types. The MOB byte-size limit only applies to the SVGA_CAP2_CURSOR_MOB path (vmw_cursor_mob_size() returns 0 for GB_ONLY); compute the required MOB size in 64-bit to avoid overflow when very large dimensions are requested. In prepare_fb only call vmw_cursor_mob_get()/_map() for VMW_CURSOR_UPDATE_MOB -- the GB_ONLY path uses bo->map.virtual directly and would otherwise be silently downgraded to NONE on hosts without SVGA_CAP2_CURSOR_MOB (where vmw_cursor_mob_get() always returns -EINVAL). Degrade the update to NONE if vmw_cursor_mob_get() or vmw_cursor_mob_map() fails so the update path does not run with a NULL backi",
    "evidence": "osv:CVE-2026-80701",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.44",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.8",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-80701",
      "aliases": [
        "CVE-2026-80701"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "965544150d1cadf0e8f5bb6c13c19697e46e1429"
                },
                {
                  "fixed": "1eb4f796695be39e0b5c4383350033ced9ade703"
                },
                {
                  "fixed": "9109b7935b9c058b75348610ef8437c52f9020e3"
                },
                {
                  "fixed": "d5ed8749168ad13c0dbaa8300f68d854b6076966"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80701.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.16.0"
                },
                {
                  "fixed": "6.18.44"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.1.8"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80701.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:49.616444439Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1eb4f796695be39e0b5c4383350033ced9ade703",
        "https://git.kernel.org/stable/c/9109b7935b9c058b75348610ef8437c52f9020e3",
        "https://git.kernel.org/stable/c/d5ed8749168ad13c0dbaa8300f68d854b6076966",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80701.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-80701",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80701.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-80701",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 518094,
  "published_at": "2026-08-28T06:53:04.652+00:00"
}