CVE-2021-47123 io_uring: fix ltout double free on completion race

2024-03-1520:14:28

Linux

www.cve.org

linux kernel

vulnerability resolved

use-after-free

linked timeout

io_uring

cve-2021-47123

6.8 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

9.2%

JSON

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

io_uring: fix ltout double free on completion race

Always remove linked timeout on io_link_timeout_fn() from the master
request link list, otherwise we may get use-after-free when first
io_link_timeout_fn() puts linked timeout in the fail path, and then
will be found and put on master’s free.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "fs/io_uring.c"
    ],
    "versions": [
      {
        "version": "90cd7e424969",
        "lessThan": "1f64f5e903b9",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "90cd7e424969",
        "lessThan": "447c19f3b507",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "fs/io_uring.c"
    ],
    "versions": [
      {
        "version": "5.11",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.11",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.12.10",
        "lessThanOrEqual": "5.12.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.13",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]