{"id":"CVE-2026-53244","summary":"VFS: fix possible failure to unlock in nfsd4_create_file()","details":"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-\u003eatomic_create is not supported).\n\nThe caller - nfsd4_create_file() - is made aware of this by checking\npath-\u003edentry, 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-\u003eatomic_create, and if a call to -\u003eatomic_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-\u003edentry is always\na valid dentry, never an error-pointer.  The actual error is already\nreturned a different way.\n\nNote that if -\u003eatomic_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().","modified":"2026-07-09T03:51:29.903053709Z","published":"2026-06-25T08:39:38.468Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53244.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/e824bbd4d224cce4b5fb59cc9dcd3447fe0b7e44"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ee1f40759a50b1800c98c1c369afd5b3e44ad987"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53244.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53244"},{"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":"64a989dbd144e0622371396461b11335459692d2"},{"fixed":"ee1f40759a50b1800c98c1c369afd5b3e44ad987"},{"fixed":"e824bbd4d224cce4b5fb59cc9dcd3447fe0b7e44"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53244.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.0.0"},{"fixed":"7.0.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53244.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}