CVE-2026-53394 (GCVE-0-2026-53394)
Vulnerability from cvelistv5
Published
2026-07-19 12:01
Modified
2026-10-19 20:07
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: avoid leaking pre-allocated openowner on unconfirmed retry race When find_or_alloc_open_stateowner() encounters an unconfirmed owner, it calls release_openowner() and sets oo = NULL. Control then falls through past the `if (oo)` guard -- which would have freed any pre-allocated `new` -- and unconditionally executes `new = alloc_stateowner(...)`. If `new` was already allocated on a prior iteration, the pointer is silently overwritten and the previous allocation (slab object + owner name buffer) is leaked. This requires a race: two NFSv4.0 OPEN threads with the same owner string, where a concurrent thread inserts a new unconfirmed owner into the hash between retry iterations. The window is narrow but repeatable under adversarial conditions. Fix by adding `goto retry` after `oo = NULL` so the already-allocated `new` is reused on the next iteration rather than overwritten.
References
Impacted products
Vendor Product Version
Linux Linux Version: 23df17788c6212809848f836b10c4f85b16843a5
Version: 23df17788c6212809848f836b10c4f85b16843a5
Version: 23df17788c6212809848f836b10c4f85b16843a5
Version: 23df17788c6212809848f836b10c4f85b16843a5
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