CVE-2024-35993

2024-05-2010:15:13

416baaa9-dc9f-4396-8d5f-8c081fb06d67

web.nvd.nist.gov

linux kernel

vulnerability

resolved

folio_test_hugetlb

concurrent

split

hugetlb

hugetlbfs

refcount

memory-failure

compaction

procfs

page_mapcount

debug_vm

oops

vm_bug_on

update

6.5 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.6%

JSON

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

mm: turn folio_test_hugetlb into a PageType

The current folio_test_hugetlb() can be fooled by a concurrent folio split
into returning true for a folio which has never belonged to hugetlbfs.
This can’t happen if the caller holds a refcount on it, but we have a few
places (memory-failure, compaction, procfs) which do not and should not
take a speculative reference.

Since hugetlb pages do not use individual page mapcounts (they are always
fully mapped and use the entire_mapcount field to record the number of
mappings), the PageType field is available now that page_mapcount()
ignores the value in this field.

In compaction and with CONFIG_DEBUG_VM enabled, the current implementation
can result in an oops, as reported by Luis. This happens since 9c5ccf2db04b
(“mm: remove HUGETLB_PAGE_DTOR”) effectively added some VM_BUG_ON() checks
in the PageHuge() testing path.

[[email protected]: update vmcoreinfo]
Link: https://lkml.kernel.org/r/[email protected]

Affected configurations

Vulners

Node

linuxlinux_kernelRange6.6–6.6.30

linuxlinux_kernelRange6.7.0–6.8.9

linuxlinux_kernelRange6.9.0≥

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "include/linux/page-flags.h",
      "include/trace/events/mmflags.h",
      "kernel/vmcore_info.c",
      "mm/hugetlb.c"
    ],
    "versions": [
      {
        "version": "9c5ccf2db04b",
        "lessThan": "2431b5f2650d",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "9c5ccf2db04b",
        "lessThan": "9fdcc5b6359d",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "9c5ccf2db04b",
        "lessThan": "d99e3140a4d3",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "include/linux/page-flags.h",
      "include/trace/events/mmflags.h",
      "kernel/vmcore_info.c",
      "mm/hugetlb.c"
    ],
    "versions": [
      {
        "version": "6.6",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "6.6",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.30",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8.9",
        "lessThanOrEqual": "6.8.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.9",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]