CVE-2021-47412
block: don't call rq_qos_ops->done_bio if the bio isn't tracked
- Published
- Updated
- Reserved
- Assigned by
- Linux
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.
Timeline
ID reserved
By Linux
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.23% · top 86% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 67b42d0bf7a8fd1ec0cf1acdc9550e688d7c8578 – < db60edbfff332a6a5477c367af8125f034570989
- affected 67b42d0bf7a8fd1ec0cf1acdc9550e688d7c8578 – < 004b8f8a691205a93d9e80d98b786b2b97424d6e
- affected 67b42d0bf7a8fd1ec0cf1acdc9550e688d7c8578 – < a647a524a46736786c95cdb553a070322ca096e3
- affected 4.19
- unaffected < 4.19
- unaffected 5.10.241 – ≤ 5.10.*
- unaffected 5.14.11 – ≤ 5.14.*
- unaffected 5.15 – ≤ *
References (4)
- https://git.kernel.org/stable/c/db60edbfff332a6a5477c367af8125f034570989 (opens in a new tab)
- https://git.kernel.org/stable/c/004b8f8a691205a93d9e80d98b786b2b97424d6e (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/a647a524a46736786c95cdb553a070322ca096e3 (opens in a new tab)x_transferred
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-47412)Record last updated .