{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-89440",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-89440"
  ],
  "published": "2026-09-11T19:47:07Z",
  "summary": "mmc: via-sdmmc: stop card-detect handling on probe failure",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: via-sdmmc: stop card-detect handling on probe failure\n\nrequest_irq() registers the SD card-detect interrupt and the probe enables\nit before mmc_add_host() runs. If mmc_add_host() fails, the error path only\nunmaps the registers and returns: the interrupt stays registered, so the\nhandler keeps running against the host once it is freed. via_sdc_isr()\ndereferences sdhost and its MMIO base and schedules carddet_work, which\nvia_sdc_card_detect() also runs against freed memory through its\ncontainer_of() dereference.\n\nAdd a probe-error path that disables and frees the interrupt and cancels\ncarddet_work before unmapping. carddet_work can re-enable the device\ninterrupt via via_reset_pcictrl(), which restores PCIINTCTRL, so mask it\nagain after cancelling the work.\n\nThis issue was found by an in-house static analysis tool and confirmed by\nmanual code review.",
  "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": "6.1.188",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-89440"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5bb5327b92aae17e91c7228953c350a6ee3c94e8"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d045596706d1b25d38af4a79980b017639fea9d1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/806409f12fdb14c9e4c56a64494c9b75f356cd49"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/dde5b9c91e9fc64e54a2f186d3ae95868b4dbb02"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/efe7f25dd27e35063477b4b0e7eed3675669fd99"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2550f89589caad7402d618d7dffc038582c94b6b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c2b8a624911999399cc14822fec3e35032b3cee4"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/088eaa92fcebaa6b957ccf9635afdf39643a577d"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-14T12:06:03Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The leftover IRQ use-after-free is in the VIA VT9530 PCI SD/MMC host probe path (via_sd_probe enabling via_sdc_isr before mmc_add_host) on systems that already have this onboard/PCI reader; it is not reached by network packets or USB hotplug.\nAC:L - The driver arms the shared card-detect IRQ before mmc_add_host(); a failed add leaves via_sdc_isr registered against freed sdhost indefinitely, so a local attacker who induces device_add failure (memory pressure/reprobe) and reclaims the host slab does not depend on an uncontrolled race.\nPR:L - An unprivileged local user on a machine with this PCI reader can be present when probe fails and then spray the heap while the dangling shared IRQ fires; capability-gated PCI sysfs unbind is not required for the UAF itself, so PR:L is the higher-severity defensible bar.\nUI:N - No victim action such as inserting an SD card, mounting media, or opening a file is required; after failed probe the leftover ISR and carddet_work run from hardware or shared interrupts without another user's involvement.\nS:U - The use-after-free corrupts kernel heap and IRQ/workqueue state inside the host OS; this is standard in-kernel memory corruption, not a VM escape, IOMMU/DMA isolation bypass, or other cross-authority breakout.\nC:H - via_sdc_isr spin_locks and dereferences the freed via_crdr_mmc_host (MMIO bases and status registers) and may queue carddet_work that recovers the same object via container_of(), a kernel UAF that enables arbitrary disclosure via slab reuse.\nI:H - The same UAF lets a reclaimed host object supply lock, MMIO, and work pointers used for MMIO writes, work scheduling, and via_reset_pcictrl, enabling heap spraying and control-flow hijack rather than a crash-only outcome.\nA:H - IRQ-context dereference of freed sdhost after iounmap and devm mmc_free_host causes a kernel oops or panic even without full exploitation, so availability impact is High."
    }
  }
}