CVE-2026-53154: linux

Vulnerability summary

CVE-2026-53154 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.8% of scored vulnerabilities.

Timeline

1. 25-06-2026
   PublishedVulnerability first disclosed.

Description

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: restore reservation on error in hugetlb folio copy paths Two sites in mm/hugetlb.c allocate a hugetlb folio via alloc_hugetlb_folio() (consuming a VMA reservation) and then call copy_user_large_folio(), which became int-returning in commit 1cb9dc4b475c ("mm: hwpoison: support recovery from HugePage copy-on-write faults") and can now fail (e.g. -EHWPOISON on a hwpoisoned source page). On the failure path, folio_put() restores the global hugetlb pool count through free_huge_folio(), but the per-VMA reservation map entry is left marked consumed: - hugetlb_mfill_atomic_pte() resubmission path (UFFDIO_COPY) - copy_hugetlb_page_range() fork-time CoW path when hugetlb_try_dup_anon_rmap() fails (rare: pinned hugetlb anon folio under fork) User-visible effect: on UFFDIO_COPY into a private hugetlb VMA where the resubmission copy fails, the reservation for that address is leaked from the VMA's reserve map. A subsequent fault at the same address takes the no-reservation path, and under hugetlb pool pressure the task is SIGBUSed at an address it had previously reserved. The fork-time CoW path leaks the same way in the child VMA's reserve map, though it requires the much rarer combination of pinned hugetlb anon page + hwpoisoned source. Add the missing restore_reserve_on_error() call before folio_put() on both error paths.

• CWE-772Missing Release of Resource after Effective LifetimeThe product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.