Bug 2536791 (CVE-2026-92481)

Summary: CVE-2026-92481 kernel: pinctrl: mediatek: free EINT resources on unbind
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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A flaw was found in the Linux kernel's pinctrl: mediatek driver. When the driver is unloaded, it fails to properly release External Interrupt (EINT) resources. This oversight can result in the system attempting to access memory that has already been freed, potentially leading to system instability or a denial of service (DoS).
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Description OSIDB Bzimport 2026-09-17 19:33:57 UTC 
In the Linux kernel, the following vulnerability has been resolved:

pinctrl: mediatek: free EINT resources on unbind

mtk_eint_do_init() creates an IRQ domain, populates it with a mapping for
every EINT line and installs a chained handler on the parent interrupt,
but none of these are ever released. This was harmless while the drivers
were built-in, but now that they can be built as modules and
unbound/rmmod'd it leaves behind a dangling IRQ domain, interrupt mappings
whose chip data points at freed memory, and a chained handler that keeps
firing into that freed data.

The plain allocations in mtk_eint_do_init() already use the device-managed
devm_*() helpers, so tear the remaining resources down the same way:
register a devm action that detaches the chained handler, waits for any
in-flight handler to finish, disposes of the per-line mappings and removes
the IRQ domain. This mirrors the device-managed lifecycle adopted for the
GPIO chip and keeps the whole EINT setup self-cleaning on unbind.
Comment 1 gkamathe 2026-09-20 08:53:24 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-92481.mbox