In the Linux kernel, the following vulnerability has been resolved: nfsd: avoid leaking pre...
🔗 CVE IDs covered (1)
📋 Description
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 (6)
- https://nvd.nist.gov/vuln/detail/CVE-2026-53394
- https://git.kernel.org/stable/c/017a6150106b054cc84d1b0582d97bd3a74d4281
- https://git.kernel.org/stable/c/57aee7a35bb12753057c5b65d72d1f46c0e95b07
- https://git.kernel.org/stable/c/a10bf67fe06469a71a401f72f328237345d553c0
- https://git.kernel.org/stable/c/c9aefb2b5f11337c9202c5bd0c45d71198449718
- https://github.com/advisories/GHSA-3gwr-8cwh-87h2