CVE-2024-35880 io_uring/kbuf: hold io_buffer_list reference over mmap

2024-05-1908:34:37

Linux

www.cve.org

linux kernel

vulnerability

io_uring/kbuf

mmap

buffer list

reference

unregistered

rcu

AI Score

6.6

Confidence

Low

EPSS

Percentile

15.5%

JSON

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

io_uring/kbuf: hold io_buffer_list reference over mmap

If we look up the kbuf, ensure that it doesn’t get unregistered until
after we’re done with it. Since we’re inside mmap, we cannot safely use
the io_uring lock. Rely on the fact that we can lookup the buffer list
under RCU now and grab a reference to it, preventing it from being
unregistered until we’re done with it. The lookup returns the
io_buffer_list directly with it referenced.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "io_uring/io_uring.c",
      "io_uring/kbuf.c",
      "io_uring/kbuf.h"
    ],
    "versions": [
      {
        "version": "09f7520048ea",
        "lessThan": "65938e81df21",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "5cf4f52e6d8a",
        "lessThan": "5fd8e2359498",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "5cf4f52e6d8a",
        "lessThan": "561e4f9451d6",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "io_uring/io_uring.c",
      "io_uring/kbuf.c",
      "io_uring/kbuf.h"
    ],
    "versions": [
      {
        "version": "6.7",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "6.7",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.26",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8.5",
        "lessThanOrEqual": "6.8.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.9",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]