{"id":"CVE-2026-53154","title":"mm/hugetlb: restore reservation on error in hugetlb folio copy paths","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/hugetlb: restore reservation on error in hugetlb folio copy paths\n\nTwo sites in mm/hugetlb.c allocate a hugetlb folio via\nalloc_hugetlb_folio() (consuming a VMA rese…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < 8d6e1dd3ad1340cd8b6d554b7aa93d8f0a1c6d38","Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < e47bf16af3c45470ea32f2241fa69aefe0dd61bd","Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < c72469ac0f274bde3f0df60a4584e14a123d0aa6","Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < 45e33d43243d71d089af42f5077b8213cee6610f","Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < 40c81856e622a9dc59294a90d169ac07ea25b0b0","Linux 6.4"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:21:15.298578Z"},"published":"2026-06-25","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:24:05.309Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53154","references":[{"url":"https://git.kernel.org/stable/c/8d6e1dd3ad1340cd8b6d554b7aa93d8f0a1c6d38"},{"url":"https://git.kernel.org/stable/c/e47bf16af3c45470ea32f2241fa69aefe0dd61bd"},{"url":"https://git.kernel.org/stable/c/c72469ac0f274bde3f0df60a4584e14a123d0aa6"},{"url":"https://git.kernel.org/stable/c/45e33d43243d71d089af42f5077b8213cee6610f"},{"url":"https://git.kernel.org/stable/c/40c81856e622a9dc59294a90d169ac07ea25b0b0"}],"tags":["cve.org"],"epss":0.00122,"epssPercentile":0.01992,"ingestedAt":"2026-11-06T16:57:43.275Z","slug":"CVE-2026-53154","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmm/hugetlb: restore reservation on error in hugetlb folio copy paths\n\nTwo sites in mm/hugetlb.c allocate a hugetlb folio via\nalloc_hugetlb_folio() (consuming a VMA reservation) and then call\ncopy_user_large_folio(), which became int-returning in commit 1cb9dc4b475c\n(\"mm: hwpoison: support recovery from HugePage copy-on-write faults\") and\ncan now fail (e.g.  -EHWPOISON on a hwpoisoned source page).  On the\nfailure path, folio_put() restores the global hugetlb pool count through\nfree_huge_folio(), but the per-VMA reservation map entry is left marked\nconsumed:\n\n  - hugetlb_mfill_atomic_pte() resubmission path (UFFDIO_COPY)\n  - copy_hugetlb_page_range() fork-time CoW path when\n    hugetlb_try_dup_anon_rmap() fails (rare: pinned hugetlb anon\n    folio under fork)\n\nUser-visible effect: on UFFDIO_COPY into a private hugetlb VMA where the\nresubmission copy fails, the reservation for that address is leaked from\nthe VMA's reserve map.  A subsequent fault at the same address takes the\nno-reservation path, and under hugetlb pool pressure the task is SIGBUSed\nat an address it had previously reserved.  The fork-time CoW path leaks\nthe same way in the child VMA's reserve map, though it requires the much\nrarer combination of pinned hugetlb anon page + hwpoisoned source.\n\nAdd the missing restore_reserve_on_error() call before folio_put() on both\nerror paths.\n\n## Affected\n\n- `Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < 8d6e1dd3ad1340cd8b6d554b7aa93d8f0a1c6d38`\n- `Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < e47bf16af3c45470ea32f2241fa69aefe0dd61bd`\n- `Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < c72469ac0f274bde3f0df60a4584e14a123d0aa6`\n- `Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < 45e33d43243d71d089af42f5077b8213cee6610f`\n- `Linux >= 1cb9dc4b475c7418f925ab0c97b6750007d9f52e < 40c81856e622a9dc59294a90d169ac07ea25b0b0`\n- `Linux 6.4`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}