{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-72315", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-72315", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-08-15T05:55:29.761Z", "updatedAt": "2026-10-03T10:55:48.520Z", "importedAt": "2026-10-24T01:58:25.636Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "smb: client: fix busy dentry warning on unmount after DIO", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix busy dentry warning on unmount after DIO\n\nCommit c68337442f03 (\"cifs: Fix busy dentry used after unmounting\") fixed\nthe issue in cifs where deferred close of a file led to a dentry reference\ncount not being released in umount, by flushing deferredclose_wq in\ncifs_kill_sb() to solve it.\n\nHowever, the cifs DIO path suffers from the same busy-dentry problem caused\nby a delayed dentry reference-count release:\n\n\t[dio]\t\t\t[cifsd]\t\t\t[close + umount]\nnetfs_unbuffered_write_iter_locked\n...\n\t\t\t\tcifs_demultiplex_thread\n netfs_unbuffered_write\n cifs_issue_write\n netfs_wait_for_in_progress_stream [1]\n\t\t\t\t...\n\t\t\t\t netfs_write_subrequest_terminated\n\t\t\t\t netfs_subreq_clear_in_progress\n\t\t\t\t netfs_wake_collector // wake [1]\n\t\t\t\t netfs_put_subrequest\n netfs_put_request\n queue_work(system_dfl_wq, xxx) [2]\n // dio write return\t\t\t\t\tcifs_close\n\t\t\t\t\t\t\t _cifsFileInfo_put\n\t\t\t\t\t\t\t // cfile->count 2->1\n\t\t\t\t\t\t\t --cfile->count [3]\n\n\t\t\t\t\t\t\t// umount\n\t\t\t\t\t\t\tcifs_kill_sb\n\t\t\t\t\t\t\t kill_anon_super\n\t\t\t\t\t\t\t // warning triggered!\n\t\t\t\t\t\t\t shrink_dcache_for_umount [4]\n[system_dfl_wq] [5]\nnetfs_free_request\n ...\n _cifsFileInfo_put\n // cfile->count 1->0\n --cfile->count\n queue_work(fileinfo_put_wq, xxx)\n\n[fileinfo_put_wq] [6]\ncifsFileInfo_put_work\n cifsFileInfo_put_final\n dput\n\nIf the umount path is triggered before [5], it results warning:\nBUG: Dentry 00000000eab1f070{i=9a917b66ae404fec,n=test} still in use (1)\n[unmount of cifs cifs]\n\nThe existing per-inode ictx->io_count wait in cifs_evict_inode() does not\nhelp: it lives in the inode eviction path, which runs after\nshrink_dcache_for_umount() has already warned about the busy dentries.\n\nFix it by adding a per-superblock outstanding-rreq counter that is\nincremented in cifs_init_request() and decremented in cifs_free_request().\nIn cifs_kill_sb(), before kill_anon_super(), wait for this counter to reach\n0 - which guarantees that all cleanup_work for this sb have run and thus\nall relevant cfile puts are queued on fileinfo_put_wq or serverclose_wq.\nThen drain the workqueue so the dentry refs are dropped.\n\nThis is a targeted wait, not a flush of the system-wide system_dfl_wq.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "0e4b8faaaebe3137bec5723ef2b3cb0437fb38fd", "status": "affected", "versionType": "git", "lessThan": "f7748b551010c021d92f0125e37f32ac0c376d8a" }, { "version": "f655467a9973f964b267871e5fef533ad5014494", "status": "affected", "versionType": "git", "lessThan": "9fc87899276af941ecf3045798887db7deb85605" }, { "version": "340cea84f691c5206561bb2e0147158fe02070be", "status": "affected", "versionType": "git", "lessThan": "f0eac9c3c3711f24efc2aaf12b8ec3e54a38c214" }, { "version": "340cea84f691c5206561bb2e0147158fe02070be", "status": "affected", "versionType": "git", "lessThan": "75f5c412fa867efa0bf9b646bffe0d912109e84a" }, { "version": "708c276f516d27beaded7f372ac8111cee43926c", "status": "affected", "versionType": "git" }, { "version": "0629a1a187e424373364d681b42b101894bdb548", "status": "affected", "versionType": "git" }, { "version": "30afc6ea72cc6cf7c8d579e79b64232801c38d08", "status": "affected", "versionType": "git" }, { "version": "6.12.78", "status": "affected", "versionType": "semver", "lessThan": "6.12.112" }, { "version": "6.18.20", "status": "affected", "versionType": "semver", "lessThan": "6.18.54" }, { "version": "6.1.167", "status": "affected", "versionType": "semver", "lessThan": "6.2" }, { "version": "6.6.130", "status": "affected", "versionType": "semver", "lessThan": "6.7" }, { "version": "6.19.10", "status": "affected", "versionType": "semver", "lessThan": "6.20" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "7.0", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "7.0" }, { "version": "6.12.112", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.54", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.1.5", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.1.*" }, { "version": "7.2", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }