{"id":"CVE-2023-53511","title":"io_uring: fix fget leak when fs don't support nowait buffered read","summary":"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 re…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= a196c78b5443fc61af2c0490213b9d125482cbd1 < 75a499fc9d66a32271e2b3e4ca71156e8ad3b484","Linux >= a196c78b5443fc61af2c0490213b9d125482cbd1 < 10fb2e16ee6ffaf1716b9e90d007e6b300bfa457","Linux >= a196c78b5443fc61af2c0490213b9d125482cbd1 < 54aa7f2330b82884f4a1afce0220add6e8312f8b","Linux cef27a7d36026bd3c86f4fdfb4611ebbe2814af4","Linux >= 5.17.9 < 5.18","Linux 5.18"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T20:22:39.001478Z"},"published":"2025-10-01","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:31:12.425Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2023-53511","references":[{"url":"https://git.kernel.org/stable/c/75a499fc9d66a32271e2b3e4ca71156e8ad3b484"},{"url":"https://git.kernel.org/stable/c/10fb2e16ee6ffaf1716b9e90d007e6b300bfa457"},{"url":"https://git.kernel.org/stable/c/54aa7f2330b82884f4a1afce0220add6e8312f8b"}],"tags":["cve.org"],"epss":0.00146,"epssPercentile":0.03901,"ingestedAt":"2026-11-05T22:38:31.804Z","slug":"CVE-2023-53511","body":"## Overview\n\nIn 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->file, leak happens\n\nThis was introduced by commit a196c78b5443 in v5.18. Fix it by don't\nre-assign req->file 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\n\n## Affected\n\n- `Linux >= a196c78b5443fc61af2c0490213b9d125482cbd1 < 75a499fc9d66a32271e2b3e4ca71156e8ad3b484`\n- `Linux >= a196c78b5443fc61af2c0490213b9d125482cbd1 < 10fb2e16ee6ffaf1716b9e90d007e6b300bfa457`\n- `Linux >= a196c78b5443fc61af2c0490213b9d125482cbd1 < 54aa7f2330b82884f4a1afce0220add6e8312f8b`\n- `Linux cef27a7d36026bd3c86f4fdfb4611ebbe2814af4`\n- `Linux >= 5.17.9 < 5.18`\n- `Linux 5.18`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}