CVE-2021-47412
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Record status
- Modified
Affected
- Linux Kernel < 5.10.241
- Linux Kernel < 5.14.11
- Linux Kernel 5.15
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-47412.md and follow it. Check whether this project is affected by CVE-2021-47412. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3
- https://git.kernel.org/stable/c/db60edbfff332a6a5477c367af8125f034570989
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3
References
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3
- https://git.kernel.org/stable/c/db60edbfff332a6a5477c367af8125f034570989
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html