{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90204", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.792Z", "datePublished": "2026-09-17T16:07:20.845Z", "dateUpdated": "2026-10-21T12:50:24.645Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:50:24.645Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: validate DIO orphan slot during inode read\n\n[BUG]\nA corrupted append-DIO dinode (high byte at offset 0xa1\ncorrupted from 0 to 1) can carry an i_dio_orphaned_slot\noutside the mounted filesystem slot range and trigger a\nuse-after-free error:\n\nBUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102\nRead of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85\nCall Trace:\n ...\n ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102\n ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840\n ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline]\n ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295\n evict+0x38e/0x8f0 fs/inode.c:810\n iput_final fs/inode.c:1914 [inline]\n iput fs/inode.c:1966 [inline]\n iput+0x55b/0x8b0 fs/inode.c:1926\n ocfs2_recover_orphans+0x610/0xe40 fs/ocfs2/journal.c:2374\n ocfs2_complete_recovery+0x5af/0xd00 fs/ocfs2/journal.c:1373\n ...\n\n[CAUSE]\nocfs2_del_inode_from_orphan() uses i_dio_orphaned_slot to index the\nslot-local system inode cache. The dinode validator does not check\nthis active slot, so an out-of-range value produces an invalid cache\nentry pointer that is dereferenced as an inode pointer.\n\n[FIX]\nReject an active i_dio_orphaned_slot outside the slot range during\ndinode validation, before DIO orphan recovery can consume it." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bad i_dio_orphaned_slot is an on-disk ocfs2_dinode field (offset 0xa0) consumed by ocfs2_del_inode_from_orphan() after ocfs2_validate_inode_block() along ocfs2_fill_super→ocfs2_complete_mount_recovery→ocfs2_recover_orphans (or ocfs2_add_inode_to_orphan on append DIO). No network protocol carries this slot.\nAC:L - A dinode with OCFS2_DIO_ORPHANED_FL and i_dio_orphaned_slot >= osb->max_slots (the reported 0xa1 0→1 flip yields slot 256) makes get_local_system_inode() index slot*NUM_LOCAL_SYSTEM_INODES past the kzalloc(max_slots*NUM_LOCAL_SYSTEM_INODES) cache and igrab the out-of-range pointer with no race.\nPR:N - ocfs2_fs_type lacks FS_USERNS_MOUNT, so mount_capable() requires init-namespace CAP_SYS_ADMIN. The higher-severity case is a crafted loop/LUN image whose recovery runs when an administrator mounts it, so the attacker needs no account or capability on the victim.\nUI:R - The attacker-supplied ocfs2 image must be mounted via ocfs2_fill_super so ocfs2_complete_mount_recovery() can walk DIO orphan dirents and call ocfs2_del_inode_from_orphan() on the forged i_dio_orphaned_slot. That mount is the required victim action.\nS:U - igrab() of the out-of-range local_system_inodes[] pointer and later ocfs2_inode_lock() stay inside the kernel that mounted the volume; this is not a KVM/Xen guest-to-host escape or IOMMU/DMA bypass.\nC:H - get_local_system_inode() reads an 8-byte inode pointer past the slot-local cache, then igrab() and ocfs2_inode_lock() treat it as a live inode. KASAN reported slab-use-after-free in ocfs2_get_system_file_inode(); a UAF inode object yields an arbitrary kernel read.\nI:H - After igrab() on the OOB/UAF pointer, ocfs2_del_inode_from_orphan() takes inode_lock and ocfs2_inode_lock on that object and journals orphan-dir mutations through it, which is a type-confused write/control-flow primitive on a freed or adjacent heap object.\nA:H - igrab() on a garbage or I_FREEING pointer hits BUG_ON(!inode) in ocfs2_get_system_file_inode() or the KASAN UAF oops shown on the ocfs2_recover_orphans mount-recovery path, which is a kernel crash." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ocfs2/inode.c" ], "versions": [ { "version": "06ee5c75b57564435933fc0ffa72dc18a2fda0e7", "lessThan": "eacdd27ca829747d4372fbae8617151072a4d1e5", "status": "affected", "versionType": "git" }, { "version": "06ee5c75b57564435933fc0ffa72dc18a2fda0e7", "lessThan": "8f7a2c5cf23d437acab7f3e739bfcad0f443c554", "status": "affected", "versionType": "git" }, { "version": "06ee5c75b57564435933fc0ffa72dc18a2fda0e7", "lessThan": "e35fa6eb4d2a39f8049f62361a4b44930882b5f8", "status": "affected", "versionType": "git" }, { "version": "06ee5c75b57564435933fc0ffa72dc18a2fda0e7", "lessThan": "418e0ae42fa769d354b15e62c01a00413024755b", "status": "affected", "versionType": "git" }, { "version": "06ee5c75b57564435933fc0ffa72dc18a2fda0e7", "lessThan": "bb88131c9831075b8dc08cdd375743e5d44c7ca2", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ocfs2/inode.c" ], "versions": [ { "version": "4.0", "status": "affected" }, { "version": "0", "lessThan": "4.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "4.0", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.12.114" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.18.52" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/eacdd27ca829747d4372fbae8617151072a4d1e5" }, { "url": "https://git.kernel.org/stable/c/8f7a2c5cf23d437acab7f3e739bfcad0f443c554" }, { "url": "https://git.kernel.org/stable/c/e35fa6eb4d2a39f8049f62361a4b44930882b5f8" }, { "url": "https://git.kernel.org/stable/c/418e0ae42fa769d354b15e62c01a00413024755b" }, { "url": "https://git.kernel.org/stable/c/bb88131c9831075b8dc08cdd375743e5d44c7ca2" } ], "title": "ocfs2: validate DIO orphan slot during inode read", "x_generator": { "engine": "bippy-1.2.0" } } } }