{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  drm/cirrus-qemu: Validate BAR0 size during probe  The `cirrus-qemu` driver relies on `CIRRUS_VRAM_SIZE` (4 MB) to validate framebuffer sizes. However, during PCI probe, the driver mapped BAR0 without verifying that its size matches `CIRRUS_VRAM_SIZE`.  If a PCI device with a BAR0 smaller than 4 MB is bound to the driver, the mapped VRAM will be smaller than expected. Because validation checks assume 4 MB VRAM, framebuffers larger than the mapped memory can be created.  When the display plane is updated (e.g. during release), `cirrus_primary_plane_helper_atomic_update()` copies the framebuffer to VRAM using `drm_fb_memcpy()`. Writing past the end of the mapped I/O memory causes a supervisor write page fault:  BUG: unable to handle page fault for address: ffffc9000389c000 ... RIP: 0010:memcpy_toio+0x7c/0xe0 arch/x86/lib/iomem.c:110 ... Call Trace:  \u003cTASK\u003e  iosys_map_memcpy_to include/linux/iosys-map.h:285 [inline]  drm_fb_memcpy+0x325/0x5d0 drivers/gpu/drm/drm_format_helper.c:442  cirrus_primary_plane_helper_atomic_update+0x98a/0xb00  drivers/gpu/drm/tiny/cirrus-qemu.c:358  drm_atomic_helper_commit_planes+0x626/0xea0  drivers/gpu/drm/drm_atomic_helper.c:3038  drm_atomic_helper_commit_tail+0x60/0x510  drivers/gpu/drm/drm_atomic_helper.c:1989  commit_tail+0x2b1/0x3c0 drivers/gpu/drm/drm_atomic_helper.c:2074  drm_atomic_helper_commit+0xa77/0xb10  drivers/gpu/drm/drm_atomic_helper.c:2312  Fix this by validating in `cirrus_pci_probe()` that the PCI BAR0 resource is not less than `CIRRUS_VRAM_SIZE`, returning `-ENODEV` if it is less.",
  "id": "DEBIAN-CVE-2026-98142",
  "modified": "2026-09-26T04:47:39.704840141Z",
  "published": "2026-09-25T11:17:45.710Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-98142"
    }
  ],
  "upstream": [
    "CVE-2026-98142"
  ]
}