CVE-2021-47316 (GCVE-0-2021-47316)
Vulnerability from cvelistv5
Published
2024-05-21 14:35
Modified
2026-10-14 12:12
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix NULL dereference in nfs3svc_encode_getaclres In error cases the dentry may be NULL. Before 20798dfe249a, the encoder also checked dentry and d_really_is_positive(dentry), but that looks like overkill to me--zero status should be enough to guarantee a positive dentry. This isn't the first time we've seen an error-case NULL dereference hidden in the initialization of a local variable in an xdr encoder. But I went back through the other recent rewrites and didn't spot any similar bugs.
References
Impacted products
Vendor Product Version
Linux Linux Version: d505e66191072748620fc0af038cea4e4da0e3cd
Version: 20798dfe249a01ad1b12eec7dbc572db5003244a
Version: 20798dfe249a01ad1b12eec7dbc572db5003244a
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