{"id":"CVE-2023-53511","summary":"io_uring: fix fget leak when fs don't support nowait buffered read","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix fget leak when fs don't support nowait buffered read\n\nHeming reported a BUG when using io_uring doing link-cp on ocfs2. [1]\n\nDo the following steps can reproduce this BUG:\nmount -t ocfs2 /dev/vdc /mnt/ocfs2\ncp testfile /mnt/ocfs2/\n./link-cp /mnt/ocfs2/testfile /mnt/ocfs2/testfile.1\numount /mnt/ocfs2\n\nThen umount will fail, and it outputs:\numount: /mnt/ocfs2: target is busy.\n\nWhile tracing umount, it blames mnt_get_count() not return as expected.\nDo a deep investigation for fget()/fput() on related code flow, I've\nfinally found that fget() leaks since ocfs2 doesn't support nowait\nbuffered read.\n\nio_issue_sqe\n|-io_assign_file  // do fget() first\n  |-io_read\n  |-io_iter_do_read\n    |-ocfs2_file_read_iter  // return -EOPNOTSUPP\n  |-kiocb_done\n    |-io_rw_done\n      |-__io_complete_rw_common  // set REQ_F_REISSUE\n    |-io_resubmit_prep\n      |-io_req_prep_async  // override req-\u003efile, leak happens\n\nThis was introduced by commit a196c78b5443 in v5.18. Fix it by don't\nre-assign req-\u003efile if it has already been assigned.\n\n[1] https://lore.kernel.org/ocfs2-devel/ab580a75-91c8-d68a-3455-40361be1bfa8@linux.alibaba.com/T/#t","modified":"2026-04-02T09:44:21.955407Z","published":"2025-10-01T11:46:00.185Z","related":["SUSE-SU-2025:03615-1","SUSE-SU-2025:3761-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53511.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/10fb2e16ee6ffaf1716b9e90d007e6b300bfa457"},{"type":"WEB","url":"https://git.kernel.org/stable/c/54aa7f2330b82884f4a1afce0220add6e8312f8b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/75a499fc9d66a32271e2b3e4ca71156e8ad3b484"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53511.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53511"},{"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":"a196c78b5443fc61af2c0490213b9d125482cbd1"},{"fixed":"75a499fc9d66a32271e2b3e4ca71156e8ad3b484"},{"fixed":"10fb2e16ee6ffaf1716b9e90d007e6b300bfa457"},{"fixed":"54aa7f2330b82884f4a1afce0220add6e8312f8b"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"0"},{"last_affected":"cef27a7d36026bd3c86f4fdfb4611ebbe2814af4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53511.json"}}],"schema_version":"1.7.5"}