CVE-2022-49786

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

blk-cgroup: properly pin the parent in blkcg_css_online

blkcg_css_online is supposed to pin the blkcg of the parent, but 397c9f46ee4d refactored things and along the way, changed it to pin the css instead. This results in extra pins, and we end up leaking blkcgs and cgroups.

A resource leak was identified in blkcg_css_online() where the current css was pinned instead of its parent, leading to extra references and memory not being freed. This issue can only be triggered by privileged users with CAP_SYS_ADMIN rights and does not allow for privilege escalation or data leakage. The leak may slowly exhaust kernel memory in systems making frequent use of cgroups and block I/O throttling.

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.