UBUNTU-CVE-2026-68356: Low severity ubuntu/linux-hwe-edge vulnerability
In the Linux kernel, the following vulnerability has been resolved: watchdog: airoha: Prevent division by zero when clock frequency is zero clkgetrate() can return 0 when the clock provider is not properly configured or the clock is unmanaged. The driver uses wdtfreq as a divisor directly in airohawdtprobe() to compute maxtimeout and in airohawdtgettimeleft() to compute the remaining time, which results in a division by zero. Add a check for wdtfreq == 0 in probe and return -EINVAL with deverrprobe() to prevent the division by zero and provide a diagnostic message.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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ubuntu/linux-aws-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1014.14~24.04.1 - Upgrade
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ubuntu/linux-azure-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17~24.04.1 - Upgrade
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ubuntu/linux-azure-fde-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1016.16~24.04.1 - Upgrade
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ubuntu/linux-gcp-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1014.14~24.04.1 - Upgrade
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ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-38.38~24.04.4 - Upgrade
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ubuntu/linux-nvidia-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1024.25~24.04.1 - Upgrade
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ubuntu/linux-oracle-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1013.13~24.04.1 - Upgrade
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ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1~24.04.1 - Upgrade
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ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-38.38 - Upgrade
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ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1014.14 - Upgrade
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ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 7.0.0-1016.16 - Upgrade
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ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1014.14 - Upgrade
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ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 7.0.0-1008.9 - Upgrade
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ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1015.15 - Upgrade
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ubuntu/linux-nvidia-bosto a version that resolves this vulnerability.Fixed in 7.0.0-2022.23 - Upgrade
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ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1015.15 - Upgrade
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ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1013.13 - Upgrade
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ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1 - Upgrade
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ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1 - Compensating control
In airoha_wdt_probe(), check whether wdt_freq == 0; return -EINVAL using dev_err_probe() with a diagnostic message before using wdt_freq as a divisor, preventing division-by-zero calculations of max_timeout and remaining time.
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems using the Airoha watchdog driver are exposed when its watchdog clock rate is reported as zero. The affected Ubuntu kernel package families listed are linux-riscv, linux-realtime, linux-hwe-edge, linux-azure, linux-gcp, linux-azure-fde, linux-gke, and linux-aws-5.0.
What condition is required to trigger the failure?
The watchdog clock provider must be improperly configured or unmanaged such that clk_get_rate() returns zero. The driver then uses that zero frequency as a divisor while calculating the maximum timeout or remaining watchdog time.
How can I identify an affected configuration before updating?
Check whether the Airoha watchdog driver is in use and whether its clock rate resolves to zero. A patched driver rejects this condition during probe with -EINVAL and emits a diagnostic through dev_err_probe().
What mitigation is available if an updated kernel cannot be deployed immediately?
Ensure the Airoha watchdog clock provider is correctly configured and managed so that it reports a nonzero clock frequency. This prevents the driver from using zero as a divisor.