{"id":"CVE-2025-71090","summary":"nfsd: fix nfsd_file reference leak in nfsd4_add_rdaccess_to_wrdeleg()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix nfsd_file reference leak in nfsd4_add_rdaccess_to_wrdeleg()\n\nnfsd4_add_rdaccess_to_wrdeleg() unconditionally overwrites\nfp-\u003efi_fds[O_RDONLY] with a newly acquired nfsd_file. However, if\nthe client already has a SHARE_ACCESS_READ open from a previous OPEN\noperation, this action overwrites the existing pointer without\nreleasing its reference, orphaning the previous reference.\n\nAdditionally, the function originally stored the same nfsd_file\npointer in both fp-\u003efi_fds[O_RDONLY] and fp-\u003efi_rdeleg_file with\nonly a single reference. When put_deleg_file() runs, it clears\nfi_rdeleg_file and calls nfs4_file_put_access() to release the file.\n\nHowever, nfs4_file_put_access() only releases fi_fds[O_RDONLY] when\nthe fi_access[O_RDONLY] counter drops to zero. If another READ open\nexists on the file, the counter remains elevated and the nfsd_file\nreference from the delegation is never released. This potentially\ncauses open conflicts on that file.\n\nThen, on server shutdown, these leaks cause __nfsd_file_cache_purge()\nto encounter files with an elevated reference count that cannot be\ncleaned up, ultimately triggering a BUG() in kmem_cache_destroy()\nbecause there are still nfsd_file objects allocated in that cache.","modified":"2026-05-18T05:59:41.427120763Z","published":"2026-01-13T15:34:51.777Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71090.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/8072e34e1387d03102b788677d491e2bcceef6f5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c07dc84ed67c5a182273171639bacbbb87c12175"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71090.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-71090"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e7a8ebc305f26cab608e59a916a4ae89d6656c5f"},{"fixed":"c07dc84ed67c5a182273171639bacbbb87c12175"},{"fixed":"8072e34e1387d03102b788677d491e2bcceef6f5"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-71090.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.17.0"},{"fixed":"6.18.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-71090.json"}}],"schema_version":"1.7.5"}