CVE-2021-46966 ACPI: custom_method: fix potential use-after-free issue

2024-02-2718:47:03

Linux

www.cve.org

linux kernel

acpi

use-after-free

7.7 High

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

13.0%

JSON

In the Linux kernel, the following vulnerability has been resolved:

ACPI: custom_method: fix potential use-after-free issue

In cm_write(), buf is always freed when reaching the end of the
function. If the requested count is less than table.length, the
allocated buffer will be freed but subsequent calls to cm_write() will
still try to access it.

Remove the unconditional kfree(buf) at the end of the function and
set the buf to NULL in the -EINVAL error path to match the rest of
function.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/acpi/custom_method.c"
    ],
    "versions": [
      {
        "version": "4bda2b79a9d0",
        "lessThan": "1d53ca5d1310",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "5c12dadcbef8",
        "lessThan": "8b04d57f30ca",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "35b88a10535e",
        "lessThan": "90575d1d9311",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "e4467fb6ef54",
        "lessThan": "a5b26a2e362f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "03d1571d9513",
        "lessThan": "72814a94c38a",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "03d1571d9513",
        "lessThan": "62dc2440ebb5",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "03d1571d9513",
        "lessThan": "f16737caf41f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "03d1571d9513",
        "lessThan": "b7a5baaae212",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "03d1571d9513",
        "lessThan": "e483bb9a991b",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/acpi/custom_method.c"
    ],
    "versions": [
      {
        "version": "5.4",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.4",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.4.269",
        "lessThanOrEqual": "4.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.9.269",
        "lessThanOrEqual": "4.9.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.14.233",
        "lessThanOrEqual": "4.14.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.19.191",
        "lessThanOrEqual": "4.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.118",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.36",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.11.20",
        "lessThanOrEqual": "5.11.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.12.3",
        "lessThanOrEqual": "5.12.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.13",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]