CVE-2025-40146

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

blk-mq: fix potential deadlock while nr_requests grown

Allocate and free sched_tags while queue is freezed can deadlock[1], this is a long term problem, hence allocate memory before freezing queue and free memory after queue is unfreezed.

[1] https://lore.kernel.org/all/[email protected]/

The patch fixes a potential deadlock in the block multiqueue subsystem when growing nr_requests. Previously, allocation and freeing of scheduler tags occurred while the queue was frozen, leading to circular lock dependencies between freeze/unfreeze and tag updates. This bug could hang the system under heavy I/O but doesn’t allow privilege escalation - it’s a local kernel-level DoS with medium severity.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.