UBUNTU-CVE-2026-80532: Medium severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: xfs: fix another iunlink infinite loop bug in online fsck xrepiunlinkresolvebucket is supposed to reconstruct as much of the incore prev and next unlinked list pointers based on what it finds on disk and in memory before we move on to relinking the truly lost inodes back into the unlinked list. However, it's still vulnerable to infinite loops that come in via the nextunlinked pointers. Fix this problem by remembering which inodes we've already seen and checking new agino pointers against that. If a bit is already set, either this is a loop or the inode has nonzero link count. We'll deal with the second case in a subsequent patch.
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
Event History
Frequently Asked Questions
Which deployments are relevant to this issue?
The issue applies to the listed Ubuntu Linux kernel packages: linux-riscv, linux-realtime, linux-hwe-edge, linux-azure, linux-gcp, linux-azure-fde, linux-gke, and linux-aws-5.0. It concerns XFS online fsck handling of unlinked-inode lists.
What condition causes the affected code to loop indefinitely?
The loop can occur when xrep_iunlink_resolve_bucket follows next_unlinked inode pointers that form a cycle. The affected reconstruction logic did not previously track inode pointers it had already visited.
What does the fix change?
The fix records inodes already seen while processing next_unlinked pointers and checks each new allocation-group inode pointer against that record. A previously seen pointer is treated as either a loop or an inode with a nonzero link count.