CVE-2026-64291 (GCVE-0-2026-64291)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:49 – Updated: 2026-08-17 04:52
VLAI
Title
iommufd: Set veventq_depth upper bound
Summary
In the Linux kernel, the following vulnerability has been resolved: iommufd: Set veventq_depth upper bound iommufd_veventq_alloc() accepts any !0 veventq_depth from userspace, with an upper bound at U32_MAX. This leaves a vulnerability where userspace can allocate excessively large queues to exhaust kernel memory reserves. Cap the veventq_depth (maximum number of entries) to 1 << 19, matching the maximum number of entries in the SMMUv3 EVTQ (the largest use case today).
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e36ba5ab808ef6237c3148d469c8238674230e2b , < f565297edf316016be4a1a9e2eb9f39359313f43 (git)
Affected: e36ba5ab808ef6237c3148d469c8238674230e2b , < e7b5e55652746b1221b9c10ff80eae8a154101ba (git)
Affected: e36ba5ab808ef6237c3148d469c8238674230e2b , < 6ebf2eb46fbd5b40393ff8fbb847ba96925beaff (git)
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Linux Linux Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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