Skip to content
CVE Ledger
  • Newest CVEsPage
  • Recently added to KEVPage
  • Rising exploitation (EPSS)Page
  • Weekly digestPage
  • StatisticsPage
  • WatchlistPage
  • API documentationPage
  • MCP serverPage
  • Data sourcesPage
  • Data statusPage
  • ChangelogPage
  • AboutPage
  • How it's builtPage
  • Support the projectPage
Back

CVE-2025-22015

mm/migrate: fix shmem xarray update during migration

Description

In the Linux kernel, the following vulnerability has been resolved: mm/migrate: fix shmem xarray update during migration A shmem folio can be either in page cache or in swap cache, but not at the same time. Namely, once it is in swap cache, folio->mapping should be NULL, and the folio is no longer in a shmem mapping. In __folio_migrate_mapping(), to determine the number of xarray entries to update, folio_test_swapbacked() is used, but that conflates shmem in page cache case and shmem in swap cache case. It leads to xarray multi-index entry corruption, since it turns a sibling entry to a normal entry during xas_store() (see [1] for a userspace reproduction). Fix it by only using folio_test_swapcache() to determine whether xarray is storing swap cache entries or not to choose the right number of xarray entries to update. [1] https://lore.kernel.org/linux-mm/[email protected]/ Note: In __split_huge_page(), folio_test_anon() && folio_test_swapcache() is used to get swap_cache address space, but that ignores the shmem folio in swap cache case. It could lead to NULL pointer dereferencing when a in-swap-cache shmem folio is split at __xa_store(), since !folio_test_anon() is true and folio->mapping is NULL. But fortunately, its caller split_huge_page_to_list_to_order() bails out early with EBUSY when folio->mapping is NULL. So no need to take care of it here.

Timeline

  1. ID reserved

    By Linux

  2. · 3 months later

    Published

  3. · 19 months later

    Record updated

Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.

Scores

CVSS scores of CVE-2025-22015, by who scored it
Scored byCVSSScoreVector
LinuxCNA (assigner)3.1High7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVDNVD · Modified3.1Medium5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS (exploitation in 30 days)
0.23% · top 86% of all CVEs (10 Nov 2026)
CISA SSVC
Exploitation: none · Automatable: no · Technical impact: total
Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.

Affected products

  • Linux · Linux

    • affected be72d197b2281e2ee3f28017fc9be1ab17e26d16 – < 49100c0b070e900f87c8fac3be9b9ef8a30fa673
    • affected 07550b1461d4d0499165e7d6f7718cfd0e440427 – < 29124ae980e2860f0eec7355949d3d3292ee81da
    • affected fc346d0a70a13d52fe1c4bc49516d83a42cd7c4c – < c057ee03f751d6cecf7ee64f52f6545d94082aaa
    • affected fc346d0a70a13d52fe1c4bc49516d83a42cd7c4c – < 75cfb92eb63298d717b6b0118f91ba12c4fcfeb5
    • affected fc346d0a70a13d52fe1c4bc49516d83a42cd7c4c – < 60cf233b585cdf1f3c5e52d1225606b86acd08b0
    • affected 6.1.71 – < 6.1.132
    • affected 6.6.10 – < 6.6.85

  • Linux · Linux

    • affected 6.7
    • unaffected < 6.7
    • unaffected 6.1.132 – ≤ 6.1.*
    • unaffected 6.6.85 – ≤ 6.6.*
    • unaffected 6.12.21 – ≤ 6.12.*
    • unaffected 6.13.9 – ≤ 6.13.*
    • unaffected 6.14 – ≤ *

References

8

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

CVE-2025-22015 badge
[![CVE-2025-22015](https://cveledger.app/badge/CVE-2025-22015.svg)](https://cveledger.app/cve/CVE-2025-22015)

Record last updated .