CVE-2026-53062

/// Technical description

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

dm cache policy smq: fix missing locks in invalidating cache blocks

In passthrough mode, the policy invalidate_mapping operation is called

simultaneously from multiple workers, thus it should be protected by a

lock. Otherwise, we might end up with data races on the allocated blocks

counter, or even use-after-free issues with internal data structures

when doing concurrent writes.

Note that the existing FIXME in smq_invalidate_mapping() doesn't affect

passthrough mode since migration tasks don't exist there, but would need

attention if supporting fast device shrinking via suspend/resume without

target reloading.

Reproduce steps:

1. Create a cache device consisting of 1024 cache entries

dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"

dmsetup create cdata --table "0 131072 linear /dev/sdc 8192"

dmsetup create corig --table "0 262144 linear /dev/sdc 262144"

dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 of

/// 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