In the Linux kernel's md/raid1 component, the function raid1_run() calls setup_conf(), which registers a thread via md_register_thread(). If the subsequent call to 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. The fix adds md_unregister_thread() to the error handling path to properly clean up the thread, aligning with other error handling logic in the function. This vulnerability is tracked as CVE-2026-45888 and was identified through static analysis and code review.

The vulnerability causes a memory leak in the Linux kernel's RAID1 subsystem, which can lead to resource exhaustion and potentially degrade system availability. There is no impact on confidentiality or integrity. No known exploits exist in the wild.

A fix has been implemented in the Linux kernel to properly unregister the thread on error paths in raid1_run(), preventing the memory leak. Users should apply the official kernel updates that include this fix. Since no patch links are provided here, consult the Linux kernel or distribution vendor advisories for the relevant updates. No additional mitigation is required beyond applying the fix.