GHSA-9XMW-XHVX-PX4Q
Vulnerability from github – Published: 2026-09-24 18:31 – Updated: 2026-09-24 18:31In the Linux kernel, the following vulnerability has been resolved:
mm/madvise: skip device-private PMDs in cold and pageout walks
madvise_cold_or_pageout_pte_range() takes pmd_trans_huge_lock(), whose pmd_is_huge() check returns true for a device-private PMD. The subsequent !pmd_present() branch has a VM_BUG_ON() asserting migration is the only allowed non-present case; a device-private PMD trips it.
Skip device-private PMDs in that non-present branch and continue to huge_unlock before calling pmd_folio(). Downgrade the check to VM_WARN_ON_ONCE() so an unexpected PMD softleaf logs a warning rather than panicking. Drop the thp_migration_supported() guard: it expands to IS_ENABLED(CONFIG_ARCH_SUPPORTS_PMD_SOFTLEAF), and both pmd_is_migration_entry() and pmd_is_device_private_entry() already return false when that config is not selected, so the guard suppresses only the case where the warning would already be silent.
Potential trigger: an HMM-based GPU driver races with madvise(MADV_COLD)/MADV_PAGEOUT: pmd_trans_huge(*pmd) reads true, then migrate_vma_pages() flips the PMD to a device-private entry before the PMD lock is acquired.
{
"affected": [],
"aliases": [
"CVE-2026-93217"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-24T16:17:16Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/madvise: skip device-private PMDs in cold and pageout walks\n\nmadvise_cold_or_pageout_pte_range() takes pmd_trans_huge_lock(), whose\npmd_is_huge() check returns true for a device-private PMD. The subsequent\n!pmd_present() branch has a VM_BUG_ON() asserting migration is the only\nallowed non-present case; a device-private PMD trips it.\n\nSkip device-private PMDs in that non-present branch and continue to\nhuge_unlock before calling pmd_folio(). Downgrade the check to\nVM_WARN_ON_ONCE() so an unexpected PMD softleaf logs a warning rather than\npanicking. Drop the thp_migration_supported() guard: it expands to\nIS_ENABLED(CONFIG_ARCH_SUPPORTS_PMD_SOFTLEAF), and both\npmd_is_migration_entry() and pmd_is_device_private_entry() already return\nfalse when that config is not selected, so the guard suppresses only the\ncase where the warning would already be silent.\n\nPotential trigger: an HMM-based GPU driver races with\nmadvise(MADV_COLD)/MADV_PAGEOUT: pmd_trans_huge(*pmd) reads true, then\nmigrate_vma_pages() flips the PMD to a device-private entry before the PMD\nlock is acquired.",
"id": "GHSA-9xmw-xhvx-px4q",
"modified": "2026-09-24T18:31:22Z",
"published": "2026-09-24T18:31:22Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93217"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5c0d7b658cda62cd17cb3652783386d5608030ef"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d4b76d0b03cb49611312ecc4bcfb55ccdf0843e2"
}
],
"schema_version": "1.4.0",
"severity": []
}
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.
Loading timeline…
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.