Bug 2541213 (CVE-2026-97972)

Summary: CVE-2026-97972 kernel: net: macb: put the "mdio" child node reference on success
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's Cadence MACB ethernet driver. During network interface initialization, the driver fails to properly release a device tree node reference upon successful registration. Repeated device probe or bind cycles can result in a reference count leak and progressive memory leak, which may lead to a Denial of Service (DoS) due to kernel resource exhaustion.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-25 11:03:25 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: macb: put the "mdio" child node reference on success

macb_mii_init() holds the reference returned by of_get_child_by_name()
for macb_mdiobus_register() and drops it only on the error paths, so
every successful probe leaks a node reference. On a CM5, overlay
removal after four bind cycles reports

  OF: ERROR: memory leak, expected refcount 1 instead of 5

Drop the reference after registration, where __mdiobus_register() has
already taken its own for the lifetime of the bus.
Comment 1 gkamathe 2026-09-30 05:18:11 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97972.mbox