{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-90289",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-90289"
  ],
  "published": "2026-09-17T16:10:40Z",
  "summary": "drm/amd/display: Resize MST HDCP per-connector arrays to 32",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: Resize MST HDCP per-connector arrays to 32\n\nAMDGPU_DM_MAX_DISPLAY_INDEX is 31. It suggest a maximum number of\n32 connectors. But the way it's used is like MAX_DISPLAY_COUNT.\nHence we're off by one with DRM core, which supports a max of 32\nconnectors.\n\nRename AMDGPU_DM_MAX_DISPLAY_INDEX to AMDGPU_DM_MAX_DISPLAY_COUNT\nto match its actual use, and increase the size to 32 to match the\noriginally intended size.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": null,
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-90289"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0fa116a17b69a28712cdf209318e345b676d7f6c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/261e0fe4e2c99f687114b64b10b98db964b475f4"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-18T17:55:42Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - hdcp_update_display() and update_config() index hdcp_workqueue.aconnector[] with aconnector->base.index from drm_connector_init_only()'s ida_alloc_max(..., 31). The path is DRM_IOCTL_MODE_ATOMIC \u2192 drm_mode_atomic_ioctl \u2192 amdgpu_dm_atomic_commit_tail \u2192 amdgpu_dm_update_hdcp()/update_psp_stream_config(); dm_dp_mst_get_modes() is reached from DRM_IOCTL_MODE_GETCONNECTOR. The index is kernel-assigned, not a protocol field.\nAC:L - No race or layout lottery: drm_connector_init_only() can assign index 31, and dm_dp_add_mst_connector() creates MST connectors until that id is used. A DRM-master atomic commit that enables that connector calls update_config(), which does hdcp_w->aconnector[conn_index] with no bounds check. hdcp_create_workqueue() is created by default on Raven-and-later GPUs.\nPR:L - drm_mode_atomic_ioctl and drm_mode_obj_set_property_ioctl are DRM_MASTER in drm_ioctl.c; drm_mode_getconnector() only calls fill_modes when drm_is_current_master(). logind grants DRM master to the seated unprivileged video/render-group user on typical AMDGPU desktops, laptops, and cloud GPU instances, so init-namespace root is not required.\nUI:N - The DRM-master attacker triggers the OOB with their own DRM_IOCTL_MODE_ATOMIC (stream enable through update_psp_stream_config(), or Content Protection via amdgpu_dm_update_hdcp()) on the index-31 connector; no other user must mount media, open a file, or attach a display on the attacker's behalf.\nS:U - aconnector[31] overwrites the following hdcp_workqueue.mutex in the same host-kernel AMDGPU HDCP object; the corruption and any oops stay inside that kernel authority and do not cross a KVM/Xen, IOMMU, or sandbox boundary.\nC:H - hdcp_update_display() holds hdcp_w->mutex then reads aconnector[31], which overlays mutex.owner (the locked task_struct *). A non-NULL owner is treated as amdgpu_dm_connector * and drm_connector_put(&...->base) follows it. dm_dp_mst_get_modes() also copies hdcp_content_type[31]/content_protection[31] into connector state readable via GETCONNECTOR.\nI:H - hdcp_update_display() and update_config() write aconnector[31]=aconnector, storing an amdgpu_dm_connector * over mutex.owner while the lock is held. amdgpu_dm_update_hdcp() also writes hdcp_content_type[connector->index] and content_protection[connector->index] on MST. That is an out-of-bounds write into adjacent hdcp_workqueue fields.\nA:H - drm_connector_put() on mutex.owner type-confused as amdgpu_dm_connector, and later lock operations on a mutex whose owner was replaced by a connector pointer, oops or panic the kernel in amdgpu_dm_atomic_commit_tail/HDCP workqueue paths."
    }
  }
}