hugetlb: only adjust reservation during unmapping if mapcount is 0
Collected exploitation and prediction evidence
Risk source coverageCISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.
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cve-program · CVE-2026-89593
PublishedIn the Linux kernel, the following vulnerability has been resolved: hugetlb: only adjust reservation during unmapping if mapcount is 0 Since df7a6d1f6405, __unmap_hugepage_range can adjust reservations. In the case of folio mapped in both a parent and a child, if the parent unmaps the range first, the reservation adjustment will result in an underflow of the reserved count. Once the child unmaps the range, the count is restored. Change __unmap_hugepage_range() to check the mapcount before adjusting the reservation.
- Source published
- 11 Sep 2026 19:44:56 UTC
- Source modified
- 19 Oct 2026 08:49:25 UTC
- Observed here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
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CVSS 3.1 · 7.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H