Bug 2513355 (CVE-2026-68324)

Summary: CVE-2026-68324 kernel: iommu/intel: Fix out-of-bounds memset in dmar_latency_disable()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Intel IOMMU (Input/Output Memory Management Unit) driver within the Linux kernel. The `dmar_latency_disable()` function incorrectly calculates the size for a memory clear operation, leading to an out-of-bounds write. A local attacker could exploit this vulnerability to corrupt adjacent memory, potentially leading to system instability or a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-08-10 12:32:47 UTC
In the Linux kernel, the following vulnerability has been resolved:

iommu/intel: Fix out-of-bounds memset in dmar_latency_disable()

dmar_latency_disable() intends to zero out only the single
latency_statistic entry for the given type, but the memset size was
computed as sizeof(*lstat) * DMAR_LATENCY_NUM, which clears the entire
array starting from &lstat[type].

When type > 0, this writes beyond the end of the allocated array,
corrupting adjacent memory.

Fix by using sizeof(*lstat) to clear only the target entry.