CVE-2021-47412
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…
Does this matter?
Lower severity and a low EPSS score (0.23%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.23% probability · 14th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6ePatch
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3Patch
- https://git.kernel.org/stable/c/db60edbfff332a6a5477c367af8125f034570989Patch
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6ePatch
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3Patch
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.