{"cve":"CVE-2021-47365","nvd":{"published":"2024-05-21T15:15:22.563","modified":"2026-06-17T04:17:18.090","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Fix page leak\n\nThere's a loop in afs_extend_writeback() that adds extra pages to a write\nwe want to make to improve the efficiency of the writeback by making it\nlarger.  This loop stops, however, if we hit a page we can't write back\nfrom immediately, but it doesn't get rid of the page ref we speculatively\nacquired.\n\nThis was caused by the removal of the cleanup loop when the code switched\nfrom using find_get_pages_contig() to xarray scanning as the latter only\ngets a single page at a time, not a batch.\n\nFix this by putting the page on a ref on an early break from the loop.\nUnfortunately, we can't just add that page to the pagevec we're employing\nas we'll go through that and add those pages to the RPC call.\n\nThis was found by the generic/074 test.  It leaks ~4GiB of RAM each time it\nis run - which can be observed with \"top\".","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":["CWE-459"],"references":["https://git.kernel.org/stable/c/581b2027af0018944ba301d68e7af45c6d1128b5","https://git.kernel.org/stable/c/d130b5fdd42254d92948d06347940276140c927e","https://git.kernel.org/stable/c/581b2027af0018944ba301d68e7af45c6d1128b5","https://git.kernel.org/stable/c/d130b5fdd42254d92948d06347940276140c927e"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47365","score":0.00208,"percentile":0.1095,"date":"2026-11-01"},"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."]}