CVE-2026-90195 (GCVE-0-2026-90195)

Vulnerability from cvelistv5 – Published: 2026-09-17 16:07 – Updated: 2026-09-17 16:07
VLAI
Title
riscv, bpf: Fix missing sign-ext for signed 1-byte and 2-byte kfunc args
Summary
In the Linux kernel, the following vulnerability has been resolved: riscv, bpf: Fix missing sign-ext for signed 1-byte and 2-byte kfunc args On RV64, the ABI requires sign-extension for signed 1-byte and 2-byte kfunc args. However, the RV64 JIT currently does not perform sign-extension for such kfunc args. Before commit 7ce090afbf72 ("bpf: Infer zext_dst based on static register liveness analysis"), state pruning could potentially omit zero-extension of 32-bit subregisters, which inadvertently masked the above issue by making the args appear as if they had been properly sign-extended. After that commit, the problem is exposed, causing the kfunc_call/kfunc_call_test4 selftest to fail. Fix this by extending the existing sign-extension logic to handle signed 1-byte and 2-byte kfunc args as well.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 443574b033876c85a35de4c65c14f7fe092222b2 , < 555fc6f1caf00ce7005e732b688da26c0dc3c5c5 (git)
Affected: 443574b033876c85a35de4c65c14f7fe092222b2 , < 801ae90f8ce099187e6224cec7d72d07a4df0324 (git)
Affected: 443574b033876c85a35de4c65c14f7fe092222b2 , < 71dbd143be598954ae103feadd12692aeb0f2f88 (git)
Affected: 443574b033876c85a35de4c65c14f7fe092222b2 , < f2aaa621591093cfe8224a25ef2f04a3b1e304b0 (git)
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Linux Linux Affected: 6.9
Unaffected: 0 , < 6.9 (semver)
Unaffected: 6.12.110 , ≤ 6.12.* (semver)
Unaffected: 6.18.52 , ≤ 6.18.* (semver)
Unaffected: 7.2.6 , ≤ 7.2.* (semver)
Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)
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    "dateReserved": "2026-09-11T19:38:34.792Z",
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          }
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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.