CVE-2021-47412

5.5 MEDIUM
Published: May 21, 2024 Modified: November 03, 2025

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/db60edbfff332a6a5477c367af8125f034570989
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e
Source: af854a3a-2127-422b-91ae-364da2661108
Patch
https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3
Source: af854a3a-2127-422b-91ae-364da2661108
Patch

6 reference(s) from NVD

Quick Stats

CVSS v3 Score
5.5 / 10.0
EPSS (Exploit Probability)
0.0%
7th percentile
Exploitation Status
Not in CISA KEV

Affected Vendors

linux