{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-49958", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T12:17:06.048Z", "datePublished": "2024-10-21T18:02:11.702Z", "dateUpdated": "2026-08-05T11:40:41.863Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:40:41.863Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: reserve space for inline xattr before attaching reflink tree\n\nOne of our customers reported a crash and a corrupted ocfs2 filesystem. \nThe crash was due to the detection of corruption. Upon troubleshooting,\nthe fsck -fn output showed the below corruption\n\n[EXTENT_LIST_FREE] Extent list in owner 33080590 claims 230 as the next free chain record,\nbut fsck believes the largest valid value is 227. Clamp the next record value? n\n\nThe stat output from the debugfs.ocfs2 showed the following corruption\nwhere the \"Next Free Rec:\" had overshot the \"Count:\" in the root metadata\nblock.\n\n Inode: 33080590 Mode: 0640 Generation: 2619713622 (0x9c25a856)\n FS Generation: 904309833 (0x35e6ac49)\n CRC32: 00000000 ECC: 0000\n Type: Regular Attr: 0x0 Flags: Valid\n Dynamic Features: (0x16) HasXattr InlineXattr Refcounted\n Extended Attributes Block: 0 Extended Attributes Inline Size: 256\n User: 0 (root) Group: 0 (root) Size: 281320357888\n Links: 1 Clusters: 141738\n ctime: 0x66911b56 0x316edcb8 -- Fri Jul 12 06:02:30.829349048 2024\n atime: 0x66911d6b 0x7f7a28d -- Fri Jul 12 06:11:23.133669517 2024\n mtime: 0x66911b56 0x12ed75d7 -- Fri Jul 12 06:02:30.317552087 2024\n dtime: 0x0 -- Wed Dec 31 17:00:00 1969\n Refcount Block: 2777346\n Last Extblk: 2886943 Orphan Slot: 0\n Sub Alloc Slot: 0 Sub Alloc Bit: 14\n Tree Depth: 1 Count: 227 Next Free Rec: 230\n ## Offset Clusters Block#\n 0 0 2310 2776351\n 1 2310 2139 2777375\n 2 4449 1221 2778399\n 3 5670 731 2779423\n 4 6401 566 2780447\n ....... .... .......\n ....... .... .......\n\nThe issue was in the reflink workfow while reserving space for inline\nxattr. The problematic function is ocfs2_reflink_xattr_inline(). By the\ntime this function is called the reflink tree is already recreated at the\ndestination inode from the source inode. At this point, this function\nreserves space for inline xattrs at the destination inode without even\nchecking if there is space at the root metadata block. It simply reduces\nthe l_count from 243 to 227 thereby making space of 256 bytes for inline\nxattr whereas the inode already has extents beyond this index (in this\ncase up to 230), thereby causing corruption.\n\nThe fix for this is to reserve space for inline metadata at the destination\ninode before the reflink tree gets recreated. The customer has verified the\nfix." } ], "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 only path to the bug is the `OCFS2_IOC_REFLINK` ioctl (and its compat variant) issued against a locally mounted ocfs2 filesystem; the FICLONE/remap path uses different code and is not affected, so there is no remote reachability.\nAC:L - The attacker deterministically creates the preconditions itself — set an inline xattr on its own file, fragment it to 228–243 extents so the source is at tree depth 1 while the reflink target stays depth 0 with more records than the clamped `l_count` of 227, then issue the ioctl; no race or uncontrollable state is involved.\nPR:L - `ocfs2_reflink_ioctl()` performs no capability check — an ordinary unprivileged user needs only read access to the source (its own file) and write/exec on the destination directory, with `preserve=0` avoiding even the `CAP_CHOWN` test.\nUI:N - The attacker performs every step itself via its own syscalls on an already-mounted filesystem; no action by another user or administrator is required.\nS:U - Corruption and its consequences stay within the kernel/filesystem security authority of the affected node; no VM, IOMMU, or hypervisor boundary is crossed.\nC:H - Attacker-controlled inline-xattr bytes overwrite still-live extent records, so the reflinked file's `e_blkno` values point at arbitrary physical blocks of the shared device, letting an unprivileged user read other users' and root-owned file data plus filesystem metadata; the missing `l_next_free_rec <= l_count` validation in `ocfs2_validate_inode_block()` means nothing stops the reload.\nI:H - The same forged extent records give a write primitive to arbitrary disk blocks (other files' data and on-disk metadata), and the resulting `l_next_free_rec > l_count` state drives `ocfs2_insert_at_index()` to `memmove` up to 16 bytes past the end of the inode block buffer, corrupting adjacent kernel memory.\nA:H - `BUG_ON(l_next_free_rec > l_count)` in fs/ocfs2/alloc.c:1688 panics the kernel, and corruption detection via `ocfs2_error()`/`__ocfs2_abort()` forces the filesystem read-only or panics outright on clustered mounts, taking down every node sharing the storage." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ocfs2/refcounttree.c", "fs/ocfs2/xattr.c" ], "versions": [ { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "5c9807c523b4fca81d3e8e864dabc8c806402121", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "74364cb578dcc0b6c9109519d19cbe5a56afac9a", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "aac31d654a0a31cb0d2fa36ae694f4e164a52707", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "020f5c53c17f66c0a8f2d37dad27ace301b8d8a1", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "5c2072f02c0d75802ec28ec703b7d43a0dd008b5", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "637c00e06564a945e9d0edb3d78d362d64935f9f", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "9f9a8f3ac65b4147f1a7b6c05fad5192c0e3c3d9", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "96ce4c3537114d1698be635f5e36c62dc49df7a4", "status": "affected", "versionType": "git" }, { "version": "ef962df057aaafd714f5c22ba3de1be459571fdf", "lessThan": "5ca60b86f57a4d9648f68418a725b3a7de2816b0", "status": "affected", "versionType": "git" }, { "version": "3a32958d2ac96070c53d04bd8e013c97b260b5e6", "status": "affected", "versionType": "git" }, { "version": "93f26306db89c9dc37885b76a1082e6d54d23b16", "status": "affected", "versionType": "git" }, { "version": "26a849f49fb3347d126a0ed6611173f903374ef4", "status": "affected", "versionType": "git" }, { "version": "1e7e4c9ae2a78a6791a2ca91a6a400f94855f01e", "status": "affected", "versionType": "git" }, { "version": "1926bf8ae44d80c9f50103f11fc4f17e2e2bf684", "status": "affected", "versionType": "git" }, { "version": "3.0.87", "lessThan": "3.1", "status": "affected", "versionType": "semver" }, { "version": "3.2.49", "lessThan": "3.3", "status": "affected", "versionType": "semver" }, { "version": "3.4.54", "lessThan": "3.5", "status": "affected", "versionType": "semver" }, { "version": "3.9.11", "lessThan": "3.10", "status": "affected", "versionType": "semver" }, { "version": "3.10.2", "lessThan": "3.11", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ocfs2/refcounttree.c", "fs/ocfs2/xattr.c" ], "versions": [ { "version": "3.11", "status": "affected" }, { "version": "0", "lessThan": "3.11", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.323", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.285", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.227", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.168", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.113", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.55", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.10.14", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.3", "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": "3.11", "versionEndExcluding": "4.19.323" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "5.4.285" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "5.10.227" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "5.15.168" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "6.1.113" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "6.6.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "6.10.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "6.11.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.11", "versionEndExcluding": "6.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.0.87" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.2.49" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.4.54" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.9.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/5c9807c523b4fca81d3e8e864dabc8c806402121" }, { "url": "https://git.kernel.org/stable/c/74364cb578dcc0b6c9109519d19cbe5a56afac9a" }, { "url": "https://git.kernel.org/stable/c/aac31d654a0a31cb0d2fa36ae694f4e164a52707" }, { "url": "https://git.kernel.org/stable/c/020f5c53c17f66c0a8f2d37dad27ace301b8d8a1" }, { "url": "https://git.kernel.org/stable/c/5c2072f02c0d75802ec28ec703b7d43a0dd008b5" }, { "url": "https://git.kernel.org/stable/c/637c00e06564a945e9d0edb3d78d362d64935f9f" }, { "url": "https://git.kernel.org/stable/c/9f9a8f3ac65b4147f1a7b6c05fad5192c0e3c3d9" }, { "url": "https://git.kernel.org/stable/c/96ce4c3537114d1698be635f5e36c62dc49df7a4" }, { "url": "https://git.kernel.org/stable/c/5ca60b86f57a4d9648f68418a725b3a7de2816b0" } ], "title": "ocfs2: reserve space for inline xattr before attaching reflink tree", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-49958", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-10-22T13:35:29.206736Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-22T13:38:48.118Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:23:38.186Z" } } ] } }