Oracle Linux: CVE-2021-47412: ELSA-2024-7000: kernel security update (IMPORTANT)

In the Linux kernel, the following vulnerability has been resolved:
block: don't call rq_qos_ops->done_bio if the bio isn't tracked
rq_qos framework is only applied on request based driver, so:
1) rq_qos_done_bio() needn't to be called for bio based driver
2) rq_qos_done_bio() needn't to be called for bio which isn't tracked,
such as bios ended from error handling code.
Especially in bio_endio():
1) request queue is referred via bio->bi_bdev->bd_disk->queue, which
may be gone since request queue refcount may not be held in above two
cases
2) q->rq_qos may be freed in blk_cleanup_queue() when calling into
__rq_qos_done_bio()
Fix the potential kernel panic by not calling rq_qos_ops->done_bio if
the bio isn't tracked. This way is safe because both ioc_rqos_done_bio()
and blkcg_iolatency_done_bio() are nop if the bio isn't tracked.
A vulnerability was found in the Linux kernel, where improper handling of block I/O requests when a block I/O request (bio) is not tracked, the kernel erroneously calls the rq_qos_ops->done_bio function, potentially leading to use-after-free issues. This situation can occurr when the request queue is accessed after it has been freed, resulting in possible kernel panic.