CVE-2026-53394

HIGH

nfsd: avoid leaking pre-allocated openowner on unconfirmed retry race

Title source: cna
STIX 2.1

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.

Scores

CVSS v3 7.5
EPSS 0.0045
EPSS Percentile 36.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-401
Status published
Products (14)
linux/Kernel 6.10.0 - 6.12.95linux
linux/Kernel 6.13.0 - 6.18.38linux
linux/Kernel 6.19.0 - 7.1.3linux
Linux/Linux < 6.10
Linux/Linux 23df17788c6212809848f836b10c4f85b16843a5 - 017a6150106b054cc84d1b0582d97bd3a74d4281
Linux/Linux 23df17788c6212809848f836b10c4f85b16843a5 - 57aee7a35bb12753057c5b65d72d1f46c0e95b07
Linux/Linux 23df17788c6212809848f836b10c4f85b16843a5 - a10bf67fe06469a71a401f72f328237345d553c0
Linux/Linux 23df17788c6212809848f836b10c4f85b16843a5 - c9aefb2b5f11337c9202c5bd0c45d71198449718
Linux/Linux 6.10
Linux/Linux 6.12.95 - 6.12.*
... and 4 more
Published Jul 19, 2026
Tracked Since Jul 19, 2026