Bug 2541232 (CVE-2026-97969)

Summary: CVE-2026-97969 kernel: watchdog: msc313e: Fix clock leak and spurious timer in settimeout()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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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Doc Text:
A flaw was found in the Linux kernel's Mstar MSC313e watchdog driver. When adjusting the watchdog timeout setting, the driver unconditionally activates the timer even if the watchdog device is currently inactive. A local user with access to configure the watchdog device could exploit this flaw to cause an unexpected system reboot leading to a Denial of Service (DoS), or cause an unreleased clock resource leak.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-25 11:07:13 UTC 
In the Linux kernel, the following vulnerability has been resolved:

watchdog: msc313e: Fix clock leak and spurious timer in settimeout()

msc313e_wdt_settimeout() unconditionally calls msc313e_wdt_start() which
introduces two severe bugs:

1. If the watchdog is already active, calling start() again will
   increase the reference count of the clock again.  However stop() is
   only called once, the reference count is unbalance.
2. If the watchdog is stopped, calling settimeout() will start
   the hardware timer accidentally.

Factor out the register-writing logic into a helper function.  Only call
it in settimeout() if the watchdog is running.  Otherwise, simply update
`wdev->timeout`.
Comment 1 gkamathe 2026-09-30 04:52:24 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97969.mbox