CVE-2024-27007 userfaultfd: change src_folio after ensuring it's unpinned in UFFDIO_MOVE

2024-05-0105:29:08

Linux

github.com

linux kernel

vulnerability resolved

userfaultfd

src_folio

uffdio_move

memory corruption

AI Score

6.8

Confidence

Low

EPSS

Percentile

9.0%

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

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

userfaultfd: change src_folio after ensuring it’s unpinned in UFFDIO_MOVE

Commit d7a08838ab74 (“mm: userfaultfd: fix unexpected change to src_folio
when UFFDIO_MOVE fails”) moved the src_folio->{mapping, index} changing to
after clearing the page-table and ensuring that it’s not pinned. This
avoids failure of swapout+migration and possibly memory corruption.

However, the commit missed fixing it in the huge-page case.

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "adef440691ba",
        "lessThan": "df5f6e683e7f",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "adef440691ba",
        "lessThan": "c0205eaf3af9",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "mm/huge_memory.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "6.8"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "6.8",
        "versionType": "custom"
      },
      {
        "status": "unaffected",
        "version": "6.8.8",
        "versionType": "custom",
        "lessThanOrEqual": "6.8.*"
      },
      {
        "status": "unaffected",
        "version": "6.9",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "mm/huge_memory.c"
    ],
    "defaultStatus": "affected"
  }
]