VFS: fix possible failure to unlock in nfsd4_create_file()_CVE-2026-53244

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nVFS: fix possible failure to unlock in nfsd4_create_file()\n\natomic_create() in fs/namei.c drops the reference to the dentry\nwhen it returns an error.\nThis behaviour was imported into dentry_create() so that it\nwill drop the reference if an error is returned from atomic_create(),\nthough not if vfs_create() returns an error (in the case where\n->atomic_create is not supported).\n\nThe caller - nfsd4_create_file() - is made aware of this by checking\npath->dentry, which will either be a counted reference to a dentry, or\nan error pointer.\n\nHowever the change to use start_creating()/end_creating() (which landed\nshortly before the dentry_create() change landed, though was likely\ndeveloped around the same time) means that nfsd4_create_file() *needs* a\nvalid dentry so that it can unlock the parent.\n\nThe net result is that if NFSD exports a filesystem which uses\n->atomic_create, and if a call to ->atomic_create returns an error, then\nnfsd4_create_file() will pass an error pointer to end_creating()\nand the parent will not be unlocked.\n\nFix this by changing dentry_create() to make sure path->dentry is always\na valid dentry, never an error-pointer.  The actual error is already\nreturned a different way.\n\nNote that if ->atomic_create() returns a different dentry (which may not\nbe possible in practice) we are guaranteed (because it is only ever\nprovided by d_spliace_alias()) that it will have the same d_parent and\nso it will have the same effect when passed to end_creating().",
    "published": "2026-06-25T08:39:38.468Z",
    "modified": "2026-06-28T06:40:50.947Z",
    "type": "cve",
    "title": "VFS: fix possible failure to unlock in nfsd4_create_file()",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/ee1f40759a50b1800c98c1c369afd5b3e44ad987\nhttps://git.kernel.org/stable/c/e824bbd4d224cce4b5fb59cc9dcd3447fe0b7e44",
    "id": "CVE-2026-53244",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 64a989dbd144e0622371396461b11335459692d2\nLinux Linux 64a989dbd144e0622371396461b11335459692d2\nLinux Linux 7.0",
    "sourceHref": "",
    "cvss": {
        "score": 7.5,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
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            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "64a989dbd144e0622371396461b11335459692d2",
    "vendor": "Linux",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
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    "ai_version": "",
    "ai_score": 0
}