{"cve":"CVE-2021-47066","nvd":{"published":"2024-02-29T23:15:08.057","modified":"2026-08-04T10:16:43.750","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nasync_xor: increase src_offs when dropping destination page\n\nNow we support sharing one page if PAGE_SIZE is not equal stripe size. To\nsupport this, it needs to support calculating xor value with different\noffsets for each r5dev. One offset array is used to record those offsets.\n\nIn RMW mode, parity page is used as a source page. It sets\nASYNC_TX_XOR_DROP_DST before calculating xor value in ops_run_prexor5.\nSo it needs to add src_list and src_offs at the same time. Now it only\nneeds src_list. So the xor value which is calculated is wrong. It can\ncause data corruption problem.\n\nI can reproduce this problem 100% on a POWER8 machine. The steps are:\n\n  mdadm -CR /dev/md0 -l5 -n3 /dev/sdb1 /dev/sdc1 /dev/sdd1 --size=3G\n  mkfs.xfs /dev/md0\n  mount /dev/md0 /mnt/test\n  mount: /mnt/test: mount(2) system call failed: Structure needs cleaning.","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/29ffa50f33de824b5491f8239c88c4a0efdd03af","https://git.kernel.org/stable/c/53f8208e11abd6dde9480dfcb97fecdb1bc2ac18","https://git.kernel.org/stable/c/cab2e8e5997b592fdb7d02cf2387b4b8e3057174","https://git.kernel.org/stable/c/ceaf2966ab082bbc4d26516f97b3ca8a676e2af8","https://git.kernel.org/stable/c/29ffa50f33de824b5491f8239c88c4a0efdd03af"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:46:54.846886191+00:00"},"epss":{"cve":"CVE-2021-47066","score":0.00235,"percentile":0.14455,"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."]}