UBUNTU-CVE-2026-90204: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ocfs2: validate DIO orphan slot during inode read [BUG] A corrupted append-DIO dinode (high byte at offset 0xa1 corrupted from 0 to 1) can carry an idioorphanedslot outside the mounted filesystem slot range and trigger a use-after-free error: BUG: KASAN: slab-use-after-free in ocfs2getsystemfileinode+0x780/0x820 fs/ocfs2/sysfile.c:102 Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85 Call Trace: ... ocfs2getsystemfileinode+0x780/0x820 fs/ocfs2/sysfile.c:102 ocfs2wipeinode+0x292/0xf70 fs/ocfs2/inode.c:840 ocfs2deleteinode fs/ocfs2/inode.c:1155 [inline] ocfs2evictinode+0x6c9/0x1170 fs/ocfs2/inode.c:1295 evict+0x38e/0x8f0 fs/inode.c:810 iputfinal fs/inode.c:1914 [inline] iput fs/inode.c:1966 [inline] iput+0x55b/0x8b0 fs/inode.c:1926 ocfs2recoverorphans+0x610/0xe40 fs/ocfs2/journal.c:2374 ocfs2completerecovery+0x5af/0xd00 fs/ocfs2/journal.c:1373 ... [CAUSE] ocfs2delinodefromorphan() uses idioorphanedslot to index the slot-local system inode cache. The dinode validator does not check this active slot, so an out-of-range value produces an invalid cache entry pointer that is dereferenced as an inode pointer. [FIX] Reject an active idioorphanedslot outside the slot range during dinode validation, before DIO orphan recovery can consume it.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42~24.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1~24.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-42.42 - Upgrade
Upgrade
ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1016.17 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1016.18 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1015.16 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-42.42.1 - Compensating control
Update ocfs2 dinode validation to reject an active i_dio_orphaned_slot whose value is outside the mounted filesystem slot range, before DIO orphan recovery consumes it.
Event History
Frequently Asked Questions
Which Ubuntu kernel packages are in scope?
The affected software list includes ubuntu/linux, ubuntu/linux-aws, ubuntu/linux-azure, ubuntu/linux-gcp, ubuntu/linux-fips, ubuntu/linux-aws-fips, ubuntu/linux-azure-fips, and ubuntu/linux-gcp-fips.
What condition is required to trigger the failure?
The system must process a corrupted OCFS2 append-DIO dinode whose i_dio_orphaned_slot value is outside the mounted filesystem's slot range. The invalid slot is used while handling orphan cleanup and can produce an invalid system-inode cache pointer.
What is the observed security impact?
The reported failure is a slab use-after-free during OCFS2 inode eviction and orphan recovery. The supplied severity vector indicates high integrity and availability impact, with no confidentiality impact.