{"cve":"CVE-2021-47412","nvd":{"published":"2024-05-21T15:15:26.700","modified":"2026-08-04T10:17:02.490","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nblock: don't call rq_qos_ops->done_bio if the bio isn't tracked\n\nrq_qos framework is only applied on request based driver, so:\n\n1) rq_qos_done_bio() needn't to be called for bio based driver\n\n2) rq_qos_done_bio() needn't to be called for bio which isn't tracked,\nsuch as bios ended from error handling code.\n\nEspecially in bio_endio():\n\n1) request queue is referred via bio->bi_bdev->bd_disk->queue, which\nmay be gone since request queue refcount may not be held in above two\ncases\n\n2) q->rq_qos may be freed in blk_cleanup_queue() when calling into\n__rq_qos_done_bio()\n\nFix the potential kernel panic by not calling rq_qos_ops->done_bio if\nthe bio isn't tracked. This way is safe because both ioc_rqos_done_bio()\nand blkcg_iolatency_done_bio() are nop if the bio isn't tracked.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"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"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47412","score":0.00233,"percentile":0.1427,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}