Bug 2482177 (CVE-2026-46007)

Summary: CVE-2026-46007 kernel: hwmon: (powerz) Avoid cacheline sharing for DMA buffer
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's hwmon (powerz) component. This vulnerability is caused by cacheline sharing between the transfer buffer and a mutex during Direct Memory Access (DMA) operations. This architectural issue can lead to unexpected behavior or data corruption, impacting system stability. The flaw is addressed by using high-level DMA helpers to prevent cacheline sharing.
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Description OSIDB Bzimport 2026-05-27 15:14:57 UTC 
In the Linux kernel, the following vulnerability has been resolved:

hwmon: (powerz) Avoid cacheline sharing for DMA buffer

Depending on the architecture the transfer buffer may share a cacheline
with the following mutex. As the buffer may be used for DMA, that is
problematic.

Use the high-level DMA helpers to make sure that cacheline sharing can
not happen.

Also drop the comment, as the helpers are documentation enough.

https://sashiko.dev/#/message/20260408175814.934BFC19421%40smtp.kernel.org
Comment 1 Keith Grant 2026-05-27 21:07:12 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052743-CVE-2026-46007-5095@gregkh/T