github - ghsa-8g2p-p68f-4wqr

ghsa-8g2p-p68f-4wqr

Vulnerability from github

Published

2024-05-22 09:31

Modified

2024-05-22 09:31

Details

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

mm: khugepaged: skip huge page collapse for special files

The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2].

This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface.

[shy828301@gmail.com: fix vm_file check [3]]

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47491"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-22T09:15:10Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: khugepaged: skip huge page collapse for special files\n\nThe read-only THP for filesystems will collapse THP for files opened\nreadonly and mapped with VM_EXEC.  The intended usecase is to avoid TLB\nmisses for large text segments.  But it doesn\u0027t restrict the file types\nso a THP could be collapsed for a non-regular file, for example, block\ndevice, if it is opened readonly and mapped with EXEC permission.  This\nmay cause bugs, like [1] and [2].\n\nThis is definitely not the intended usecase, so just collapse THP for\nregular files in order to close the attack surface.\n\n[shy828301@gmail.com: fix vm_file check [3]]",
  "id": "GHSA-8g2p-p68f-4wqr",
  "modified": "2024-05-22T09:31:46Z",
  "published": "2024-05-22T09:31:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47491"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5fcb6fce74ffa614d964667110cf1a516c48c6d9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6d67b2a73b8e3a079c355bab3c1aef7d85a044b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a4aeaa06d45e90f9b279f0b09de84bd00006e733"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

cve-2021-47491

Vulnerability from cvelistv5

Published

2024-05-22 08:19

Modified

2024-12-19 07:43

Severity ?

Summary

In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2]. This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface. [shy828301@gmail.com: fix vm_file check [3]]

References

▼	URL	Tags
	https://git.kernel.org/stable/c/6d67b2a73b8e3a079c355bab3c1aef7d85a044b8
	https://git.kernel.org/stable/c/5fcb6fce74ffa614d964667110cf1a516c48c6d9
	https://git.kernel.org/stable/c/a4aeaa06d45e90f9b279f0b09de84bd00006e733

Impacted products

Vendor

Product

Version

▼

Linux

Version: 99cb0dbd47a15d395bf3faa78dc122bc5efe3fc0
Version: 99cb0dbd47a15d395bf3faa78dc122bc5efe3fc0
Version: 99cb0dbd47a15d395bf3faa78dc122bc5efe3fc0

Linux

Version: 5.4

Show details on NVD website

JSON

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                "timestamp": "2024-05-22T18:42:55.199651Z",
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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

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