Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unconditionally bump set->nelems before insertion In case that the set is full, a new element gets published then removed without waiting for the RCU grace period, while RCU reader can be walking over it already. To address this issue, add the element transaction even if set is full, but toggle the set_full flag to report -ENFILE so the abort path safely unwinds the set to its previous state. As for element updates, decrement set->nelems to restore it. A simpler fix is to call synchronize_rcu() in the error path. However, with a large batch adding elements to already maxed-out set, this could cause noticeable slowdown of such batches.
Affected products
linux: linux kernel
References9
- git.kernel.org/stable/c/6826131c7674329335ca25df2550163eb8a1fd0c Patch
- git.kernel.org/stable/c/ccb8c8f3c1127cf34d18c737309897c68046bf21 Patch
- git.kernel.org/stable/c/def602e498a4f951da95c95b1b8ce8ae68aa733a Patch
- git.kernel.org/stable/c/022effa9c54903858e443b1225370e6c758d03f6
- git.kernel.org/stable/c/25841e8d4241c6c3763e70ae95050f8108707b46
- git.kernel.org/stable/c/25fcaef7948912652905e96922f36583a84fffed
- git.kernel.org/stable/c/86bc4b1a0f672d47ac19f9022432cb6a2e01cb33
- git.kernel.org/stable/c/e3ccb11fc8249759d23326038c8db987ddaabc77
- cert-portal.siemens.com/productcert/html/ssa-784472.html
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 8 · as of 12 November 2026
- CWE
- CWE-416
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