CVE-2021-47412

high

Published 2024-09-24 · Modified 2024-09-24

CVSS v3

—

VIR risk

8.0

Description

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.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No vendor mitigations ingested yet for this CVE. The mitigation-content worker queues fetches as references arrive — check back in a few minutes, or see the references list below.

OS impact

OS	Version	Status	Fixed in
rocky	8	fixed
sles		affected
debian	bookworm	fixed	`5.14.12-1`
debian	bullseye	fixed	`5.10.244-1`
debian	forky	fixed	`5.14.12-1`
debian	sid	fixed	`5.14.12-1`
debian	trixie	fixed	`5.14.12-1`

References

💬 Discuss CVE-2021-47412 on VIR Community →

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.