{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-39477", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-06-25T14:23:23.746Z", "datePublished": "2024-07-05T06:55:07.268Z", "dateUpdated": "2026-08-05T11:33:30.787Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:33:30.787Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/hugetlb: do not call vma_add_reservation upon ENOMEM\n\nsysbot reported a splat [1] on __unmap_hugepage_range(). This is because\nvma_needs_reservation() can return -ENOMEM if\nallocate_file_region_entries() fails to allocate the file_region struct\nfor the reservation.\n\nCheck for that and do not call vma_add_reservation() if that is the case,\notherwise region_abort() and region_del() will see that we do not have any\nfile_regions.\n\nIf we detect that vma_needs_reservation() returned -ENOMEM, we clear the\nhugetlb_restore_reserve flag as if this reservation was still consumed, so\nfree_huge_folio() will not increment the resv count.\n\n[1] https://lore.kernel.org/linux-mm/0000000000004096100617c58d54@google.com/T/#ma5983bc1ab18a54910da83416b3f89f3c7ee43aa" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable path is reached only through local syscalls on the attacker's own address space — mmap(MAP_HUGETLB), madvise(MADV_DONTNEED), munmap, or process exit driving __unmap_hugepage_range(). There is no network- or adjacent-reachable trigger.\nAC:L - Every element of the trigger is attacker-controlled and deterministic — the private anonymous hugetlb VMA, the merged reservation region, the drained region_cache, and the middle-page unmap that forces region_del()'s split path; only the file_region kmalloc failure must be induced, which an attacker does by driving memory exhaustion (hugetlb hosts are already memory-tight, and a task that becomes an OOM victim has its GFP_KERNEL allocations fail while exit_mmap runs this exact code). Once the single ENOMEM lands, adds_in_progress stays at -1 permanently and the corruption repeats on ordinary faults without further allocation failures, so the attempt can be retried indefinitely.\nPR:L - A plain unprivileged local user suffices: hugetlb_file_setup() gates only SHM_HUGETLB on CAP_IPC_LOCK, so anonymous MAP_PRIVATE|MAP_HUGETLB mmap and MADV_DONTNEED on the resulting VMA require no capability. A non-zero hugepage pool is an administrator-side configuration, standard on database, KVM, DPDK and HPC hosts, not a privilege held by the attacker.\nUI:N - The attacker's own process performs the entire sequence — mmap, fault-in, madvise/munmap — with no action by any other user or victim process.\nS:U - The corruption is confined to kernel heap objects (struct resv_map and the slab freelist) within the same security authority; no VM, hypervisor, or IOMMU boundary is crossed.\nC:H - region_del() and get_file_region_entry_from_cache() fabricate a file_region pointing at the resv_map itself and then kfree() that interior pointer while the object is still live, producing overlapping slab objects and a freelist containing a misaligned pointer — a well-known route to reading adjacent kernel heap contents. The corrupted rw_semaphore also breaks the serialization of hugetlb page-table walks against unmapping, widening the disclosure surface.\nI:H - The bogus file_region overlays struct resv_map, so nrg->from/nrg->to and copy_hugetlb_cgroup_uncharge_info() perform out-of-bounds writes over region_cache_count and the rw_semaphore (count, owner, wait_lock) that guards private hugetlb page tables, and kfree() of an interior pointer corrupts the SLUB freelist — a controllable heap-grooming primitive toward arbitrary write and control-flow hijack. The reservation accounting is also permanently falsified, letting one process steal huge pages reserved by another.\nA:H - On CONFIG_DEBUG_VM kernels this is an immediate panic via VM_BUG_ON(!resv->region_cache_count) in region_abort() and VM_BUG_ON(adds_in_progress) in resv_map_release() — precisely the syzbot splat. Without DEBUG_VM the list poisoning, wrecked rw_semaphore (hangs/deadlock in hugetlb faults), slab corruption, and permanently inflated h->resv_huge_pages produce oopses and SIGBUS-level denial of hugepages for every user on the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/hugetlb.c" ], "versions": [ { "version": "df7a6d1f64056aec572162c5d35ed9ff86ece6f3", "lessThan": "aa998f9dcb34c28448f86e8f5490f20d5eb0eac7", "status": "affected", "versionType": "git" }, { "version": "df7a6d1f64056aec572162c5d35ed9ff86ece6f3", "lessThan": "8daf9c702ee7f825f0de8600abff764acfedea13", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/hugetlb.c" ], "versions": [ { "version": "6.9", "status": "affected" }, { "version": "0", "lessThan": "6.9", "status": "unaffected", "versionType": "semver" }, { "version": "6.9.5", "lessThanOrEqual": "6.9.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.10", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.9.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.10" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/aa998f9dcb34c28448f86e8f5490f20d5eb0eac7" }, { "url": "https://git.kernel.org/stable/c/8daf9c702ee7f825f0de8600abff764acfedea13" } ], "title": "mm/hugetlb: do not call vma_add_reservation upon ENOMEM", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-02T04:26:15.943Z" }, "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/aa998f9dcb34c28448f86e8f5490f20d5eb0eac7", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/8daf9c702ee7f825f0de8600abff764acfedea13", "tags": [ "x_transferred" ] } ] }, { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-39477", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T17:07:38.781989Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-11T17:34:39.612Z" } } ] } }