CVE-2026-90320

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

ocfs2: validate external xattr entries when reading metadata

ocfs2_validate_xattr_block() checks the xattr block header before the

block reaches higher-level xattr users, but it does not verify that a

non-indexed block's xh_count and entry offsets fit inside the block.

Indexed buckets likewise reach list/get consumers after ECC without an

entry-bounds check.

Use the flat xattr entry validator for non-indexed external xattr blocks,

and use a bucket-specific validator for indexed buckets at metadata read

time. The bucket validator keeps the entry array bounded by the first

bucket block while checking name/value offsets against the bucket block

they target.

Reject corrupted external xattr metadata before listxattr() or getxattr()

can walk out-of-range entry arrays or name/value offsets.

Validation reproduced this kernel report:

BUG: KASAN: use-after-free in ocfs2_xattr_list_entries+0xd7/0x190

Read of size 1 at addr

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References