CVE-2026-64291

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).

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxe36ba5ab808ef6237c3148d469c8238674230e2b < f565297edf316016be4a1a9e2eb9f39359313f43affected
LinuxLinuxe36ba5ab808ef6237c3148d469c8238674230e2b < e7b5e55652746b1221b9c10ff80eae8a154101baaffected
LinuxLinuxe36ba5ab808ef6237c3148d469c8238674230e2b < 6ebf2eb46fbd5b40393ff8fbb847ba96925beaffaffected
LinuxLinux6.15affected
LinuxLinux0 < 6.15unaffected
LinuxLinux6.18.39 <= 6.18.*unaffected
LinuxLinux7.1.4 <= 7.1.*unaffected
LinuxLinux7.2-rc1 <= *unaffected

Weaknesses

References