{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-50222", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T19:36:19.973Z", "datePublished": "2024-11-09T10:14:33.266Z", "dateUpdated": "2026-08-05T11:42:36.871Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:42:36.871Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niov_iter: fix copy_page_from_iter_atomic() if KMAP_LOCAL_FORCE_MAP\n\ngeneric/077 on x86_32 CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP=y with highmem,\non huge=always tmpfs, issues a warning and then hangs (interruptibly):\n\nWARNING: CPU: 5 PID: 3517 at mm/highmem.c:622 kunmap_local_indexed+0x62/0xc9\nCPU: 5 UID: 0 PID: 3517 Comm: cp Not tainted 6.12.0-rc4 #2\n...\ncopy_page_from_iter_atomic+0xa6/0x5ec\ngeneric_perform_write+0xf6/0x1b4\nshmem_file_write_iter+0x54/0x67\n\nFix copy_page_from_iter_atomic() by limiting it in that case\n(include/linux/skbuff.h skb_frag_must_loop() does similar).\n\nBut going forward, perhaps CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP is too\nsurprising, has outlived its usefulness, and should just be removed?" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable code is reached through a local `write(2)` syscall on a regular file (`shmem_file_write_iter`/`generic_perform_write` → `copy_folio_from_iter_atomic`), not through any network-facing protocol handler. Exploitation requires the ability to issue write syscalls on the target system.\nAC:H - The defect exists only when the kernel is built with CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP=y — with that option off the pre-fix and post-fix code are identical — and it is a DEBUG_KERNEL-gated x86 debug option explicitly documented \"Disable this for production systems!\", absent from production and distro kernels. The build configuration of the target, plus the need for a large-folio-backed mapping, are conditions the attacker cannot influence.\nPR:L - Any unprivileged local user with write access to a file on a large-folio-capable filesystem (e.g. /dev/shm on huge tmpfs, XFS, bcachefs) can trigger it; no capabilities, namespaces, or mount privileges are required.\nUI:N - The attacker triggers the overrun entirely from its own write syscall with attacker-chosen file offset and length; no action by another user is needed.\nS:U - The out-of-bounds write and the resulting corruption are confined to kernel memory managed by the same kernel security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - Overrunning the single-page kmap slot corrupts adjacent live kmap_local mappings of arbitrary kernel pages, and the short-copy path leaves the folio marked uptodate over a range never written in place, exposing stale page-cache contents to a subsequent read — a memory-corruption primitive leveragable for kernel information disclosure.\nI:H - Attacker-controlled data is copied past the end of the one-page temporary mapping at an attacker-influenced offset (up to the full folio size), writing into other CPUs' and outer-nested kmap_local fixmap slots and thereby modifying unrelated kernel-mapped pages.\nA:H - The reported outcome is a WARN at mm/highmem.c:622 followed by an interruptible hang, as `generic_perform_write` retries indefinitely on the zero-length copy; unmapped neighbouring fixmap PTEs and the mismatched kunmap index leave stale mappings that can also oops the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "lib/iov_iter.c" ], "versions": [ { "version": "908a1ad89466c1febf20bfe0037b84fc66f8a3f8", "lessThan": "4f7ffa83fa79dd52efbaef366c850aaaae06a469", "status": "affected", "versionType": "git" }, { "version": "908a1ad89466c1febf20bfe0037b84fc66f8a3f8", "lessThan": "3a303409f271dfe0987b8f79595138340497a32d", "status": "affected", "versionType": "git" }, { "version": "908a1ad89466c1febf20bfe0037b84fc66f8a3f8", "lessThan": "c749d9b7ebbc5716af7a95f7768634b30d9446ec", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "lib/iov_iter.c" ], "versions": [ { "version": "6.6", "status": "affected" }, { "version": "0", "lessThan": "6.6", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.60", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.7", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12", "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": "6.6", "versionEndExcluding": "6.6.60" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.11.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/4f7ffa83fa79dd52efbaef366c850aaaae06a469" }, { "url": "https://git.kernel.org/stable/c/3a303409f271dfe0987b8f79595138340497a32d" }, { "url": "https://git.kernel.org/stable/c/c749d9b7ebbc5716af7a95f7768634b30d9446ec" } ], "title": "iov_iter: fix copy_page_from_iter_atomic() if KMAP_LOCAL_FORCE_MAP", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH" } }, { "other": { "type": "ssvc", "content": { "id": "CVE-2024-50222", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2025-10-01T20:17:05.945317Z" } } } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "type": "CWE", "description": "CWE-noinfo Not enough information" } ] } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-10-01T20:27:05.080Z" } } ] } }