{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-98826",
  "modified": "2026-10-19T04:30:01Z",
  "upstream": [
    "CVE-2026-98826"
  ],
  "published": "2026-10-18T15:54:51Z",
  "summary": "rtc: ac100: Fix clock provider use-after-free on probe failure",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nrtc: ac100: Fix clock provider use-after-free on probe failure\n\nac100_rtc_register_clks() registers the RTC-32k clock with\nclk_hw_register_fixed_rate() and the clock provider with\nof_clk_add_hw_provider(). Neither is device managed, and both are\nreleased only from ac100_rtc_remove(). The driver core does not call\nremove() when probe() fails: really_probe() reaches probe_failed below\nthe device_remove() call and goes straight to releasing the device's\nmanaged resources.\n\nac100_rtc_probe() ends with\n\n\treturn devm_rtc_register_device(chip->rtc);\n\nso if that fails after the clocks have been registered, the provider is\nleft on the global of_clk_providers list holding chip->clk_data, which\nwas allocated with devm_kzalloc() and is freed while probe() unwinds. A\nlater lookup on this device tree node then reads freed memory in\nof_clk_hw_onecell_get(). Consumers that do exactly that exist in tree:\nthe wifi power sequence nodes on sun8i-a83t-bananapi-m3 and\nsun8i-a83t-cubietruck-plus take <&ac100_rtc 1>, and the sun9i-a80 boards\nroute osc32k through <&ac100_rtc 0>. The window is narrow, as\ndevm_rtc_register_device() can only fail with -ENOMEM here, but the\nprovider is left dangling whenever it does.\n\nThe RTC-32k clock is leaked on the same path. Since clk_core_lookup()\nsearches a global list that is not scoped per device, __clk_register()\nrejects the duplicate name with -EEXIST, so the leak also makes a later\nprobe of the same device fail.\n\nThe error path that returns -EINVAL when the ADDA 4M parent clock cannot\nbe found leaks the RTC-32k clock in the same way. No provider has been\nregistered at that point, so that one is a leak rather than a\nuse-after-free.\n\nRegister both with devm_clk_hw_register_fixed_rate() and\ndevm_of_clk_add_hw_provider() so that they are released whenever the\ndevice goes away, on a failed probe as well as on unbind. Devres\nreleases in reverse order of acquisition, so the provider is removed\nbefore chip->clk_data is freed, and the clkout children are now\nunregistered before their parent rather than after it.\nac100_rtc_unregister_clks() and the remove callback then have nothing\nleft to do and are removed.",
  "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-2026-98826"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/12bcd20d76703ee2baf52224d287b7fea096b12f"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9cff19ddd7f90c1f572a0f83cfc41de8f8dcbcd8"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/55ca60ba336632349f7c4585d22ba74ae355b7ce"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fcf0b58e976e83adf246b014518e49c662b96f5e"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-18T15:54:51Z"
  }
}