CVE-2022-49411 bfq: Make sure bfqg for which we are queueing requests is online

In the Linux kernel, the following vulnerability has been resolved: bfq: Make sure bfqg for which we are queueing requests is online Bios queued into BFQ IO scheduler can be associated with a cgroup that was already offlined. This may then cause insertion of this bfqgroup into a service tree. But...

CVE-2022-49411

The CVE-2022-49411 entry describes a Linux kernel BFQ IO scheduler issue where bios queued to a bfq_group tied to an offline cgroup could be inserted into the service tree and be freed when the last bio completes, causing a use-after-free. The documented fix is to always operate on an online bfq_...