VULNERABILITY INTELLIGENCE

CVE-2024-49964

CVSS score5.5 MEDIUM
EPSS probability0.20%
CISA KEVNot currently listed
Published2024-10-21
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Description

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix memfd_pin_folios free_huge_pages leak memfd_pin_folios followed by unpin_folios fails to restore free_huge_pages if the pages were not already faulted in, because the folio refcount for pages created by memfd_alloc_folio never goes to 0. memfd_pin_folios needs another folio_put to undo the folio_try_get below: memfd_alloc_folio() alloc_hugetlb_folio_nodemask() dequeue_hugetlb_folio_nodemask() dequeue_hugetlb_folio_node_exact() folio_ref_unfreeze(folio, 1); ; adds 1 refcount folio_try_get() ; adds 1 refcount hugetlb_add_to_page_cache() ; adds 512 refcount (on x86) With the fix, after memfd_pin_folios + unpin_folios, the refcount for the (unfaulted) page is 512, which is correct, as the refcount for a faulted unpinned page is 513.

Weakness classification

  • nvd@nist.gov: NVD-CWE-Other

Primary references