{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2024-26998",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2024-26998"
  ],
  "published": "2024-05-01T05:31:05Z",
  "summary": "serial: core: Clearing the circular buffer before NULLifying it",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nserial: core: Clearing the circular buffer before NULLifying it\n\nThe circular buffer is NULLified in uart_tty_port_shutdown()\nunder the spin lock. However, the PM or other timer based callbacks\nmay still trigger after this event without knowning that buffer pointer\nis not valid. Since the serial code is a bit inconsistent in checking\nthe buffer state (some rely on the head-tail positions, some on the\nbuffer pointer), it's better to have both aligned, i.e. buffer pointer\nto be NULL and head-tail possitions to be the same, meaning it's empty.\nThis will prevent asynchronous calls to dereference NULL pointer as\nreported recently in 8250 case:\n\n  BUG: kernel NULL pointer dereference, address: 00000cf5\n  Workqueue: pm pm_runtime_work\n  EIP: serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)\n  ...\n  ? serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)\n  __start_tx (drivers/tty/serial/8250/8250_port.c:1551)\n  serial8250_start_tx (drivers/tty/serial/8250/8250_port.c:1654)\n  serial_port_runtime_suspend (include/linux/serial_core.h:667 drivers/tty/serial/serial_port.c:63)\n  __rpm_callback (drivers/base/power/runtime.c:393)\n  ? serial_port_remove (drivers/tty/serial/serial_port.c:50)\n  rpm_suspend (drivers/base/power/runtime.c:447)\n\nThe proposed change will prevent ->start_tx() to be called during\nsuspend on shut down port.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.6.28-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.6.28+rpt-rpi-2712",
            "binary_version": "1:6.6.28-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.28+rpt-rpi-v6",
            "binary_version": "1:6.6.28-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.28+rpt-rpi-v7",
            "binary_version": "1:6.6.28-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.28+rpt-rpi-v7l",
            "binary_version": "1:6.6.28-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.28+rpt-rpi-v8",
            "binary_version": "1:6.6.28-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.6.28-1+rpt1": {
            "linux_commit": "0c341f47adc3578cd5f817aa20ee2b7f9ae6b23e",
            "upstream_version": "6.6.28",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.29"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2024-26998"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/7ae7104d54342433a3a73975f6569beefdd86350"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/bb1118905e875c111d7ccef9aee86ac5e4e7f985"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9cf7ea2eeb745213dc2a04103e426b960e807940"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-05-24T06:48:58Z"
  }
}