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 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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e	Patch
https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3	Patch
https://git.kernel.org/stable/c/db60edbfff332a6a5477c367af8125f034570989	Patch
https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e	Patch
https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3	Patch
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc1::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc2::::::

History

No history.

Information

Published : 2024-05-21 15:15

Updated : 2025-11-03 18:15

NVD link : CVE-2021-47412

Mitre link : CVE-2021-47412

CVE.ORG link : CVE-2021-47412

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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