CVE-2026-45888: md/raid1: fix memory leak in raid1_run()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-27 · updated 2026-06-25
Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: md/raid1: fix memory leak in raid1_run() raid1_run() calls setup_conf() which registers a thread via md_register_thread(). If raid1_set_limits() fails, the previously registered thread is not unregistered, resulting in a memory leak of the md_thread structure and the thread resource itself. Add md_unregister_thread() to the error path to properly cleanup the thread, which aligns with the error handling logic of other paths in this function. Compile tested only. Issue found using a prototype static analysis tool and code review.

Affected products

Linux kernel: from 6.9 before 6.12.75; from 6.13 before 6.18.14; from 6.19 before 6.19.4 — fixed in 6.12.75, 6.18.14, 6.19.4

How to fix

Upgrade to a fixed version: Linux kernel 6.12.75, 6.18.14, 6.19.4. Check the vendor advisory for mitigations.

References

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