{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-43404",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-43404",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-05-08T14:21:44.929Z",
    "updatedAt": "2026-05-11T22:23:55.638Z",
    "importedAt": "2026-10-24T01:58:14.884Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "mm: Fix a hmm_range_fault() livelock / starvation problem",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: Fix a hmm_range_fault() livelock / starvation problem\n\nIf hmm_range_fault() fails a folio_trylock() in do_swap_page,\ntrying to acquire the lock of a device-private folio for migration,\nto ram, the function will spin until it succeeds grabbing the lock.\n\nHowever, if the process holding the lock is depending on a work\nitem to be completed, which is scheduled on the same CPU as the\nspinning hmm_range_fault(), that work item might be starved and\nwe end up in a livelock / starvation situation which is never\nresolved.\n\nThis can happen, for example if the process holding the\ndevice-private folio lock is stuck in\n   migrate_device_unmap()->lru_add_drain_all()\nsinc lru_add_drain_all() requires a short work-item\nto be run on all online cpus to complete.\n\nA prerequisite for this to happen is:\na) Both zone device and system memory folios are considered in\n   migrate_device_unmap(), so that there is a reason to call\n   lru_add_drain_all() for a system memory folio while a\n   folio lock is held on a zone device folio.\nb) The zone device folio has an initial mapcount > 1 which causes\n   at least one migration PTE entry insertion to be deferred to\n   try_to_migrate(), which can happen after the call to\n   lru_add_drain_all().\nc) No or voluntary only preemption.\n\nThis all seems pretty unlikely to happen, but indeed is hit by\nthe \"xe_exec_system_allocator\" igt test.\n\nResolve this by waiting for the folio to be unlocked if the\nfolio_trylock() fails in do_swap_page().\n\nRename migration_entry_wait_on_locked() to\nsoftleaf_entry_wait_unlock() and update its documentation to\nindicate the new use-case.\n\nFuture code improvements might consider moving\nthe lru_add_drain_all() call in migrate_device_unmap() to be\ncalled *after* all pages have migration entries inserted.\nThat would eliminate also b) above.\n\nv2:\n- Instead of a cond_resched() in hmm_range_fault(),\n  eliminate the problem by waiting for the folio to be unlocked\n  in do_swap_page() (Alistair Popple, Andrew Morton)\nv3:\n- Add a stub migration_entry_wait_on_locked() for the\n  !CONFIG_MIGRATION case. (Kernel Test Robot)\nv4:\n- Rename migrate_entry_wait_on_locked() to\n  softleaf_entry_wait_on_locked() and update docs (Alistair Popple)\nv5:\n- Add a WARN_ON_ONCE() for the !CONFIG_MIGRATION\n  version of softleaf_entry_wait_on_locked().\n- Modify wording around function names in the commit message\n  (Andrew Morton)\n\n(cherry picked from commit a69d1ab971a624c6f112cea61536569d579c3215)",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "1afaeb8293c9addbf4f9140bdd22635fed763459",
              "status": "affected",
              "versionType": "git",
              "lessThan": "94b6d0ba4b640ba23bb6c708a59316e74e5ede63"
            },
            {
              "version": "1afaeb8293c9addbf4f9140bdd22635fed763459",
              "status": "affected",
              "versionType": "git",
              "lessThan": "7e6e2fc91d4b9b12ec6e137019532568ebcf2680"
            },
            {
              "version": "1afaeb8293c9addbf4f9140bdd22635fed763459",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b570f37a2ce480be26c665345c5514686a8a0274"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.15",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.15"
            },
            {
              "version": "6.18.19",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "6.19.9",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "version": "7.0",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}