---
id: "CVE-2026-98825"
kind: "vulnerability"
aliases: ["CVE-2026-98825"]
title: "Linux kernel: RTC driver crashes on unchecked clock error during probe"
severity: "low"
cvss: null
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["embedded", "linux-kernel", "other", "polarfire-soc"]
not_affected_if: ["other-hardware"]
published_at: "2026-10-18T16:17:36+00:00"
first_seen_at: "2026-10-23T21:57:17+00:00"
updated_at: "2026-10-25T05:14:36+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98825", "first_seen_at": "2026-10-23T21:57:17+00:00"}]
---

# Linux kernel: RTC driver crashes on unchecked clock error during probe

The Linux kernel's mpfs RTC driver passed an unchecked clock pointer into clk_get_rate(), so an error return from devm_clk_get() (such as a deferred probe) could be dereferenced and crash the kernel. The fix checks the pointer with IS_ERR() before use, matching the handling of the neighbouring clock.

_Summary, check and fix written by a model from the sources; labelled as such._

## Timeline

- 2026-10-23T21:57:17+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98825

## From the sources

In the Linux kernel, the following vulnerability has been resolved:

rtc: mpfs: fix unchecked devm_clk_get() error pointer in probe()

devm_clk_get(&pdev->dev, "rtcref")'s return value was passed straight
into clk_get_rate() without checking it for an error first, unlike the
"rtc" clock a few lines above which is correctly checked with
IS_ERR(). clk_get_rate() only guards against a NULL clk, not an error
pointer:

	if (!clk)
		return 0;
	...
	rate = clk_core_get_rate_recalc(clk->core);

so if devm_clk_get() ever returns an error pointer here (for example
ERR_PTR(-EPROBE_DEFER), which is the normal, expected outcome if the
clkcfg clock-provider this RTC depends on has not registered its
clocks yet by the time this driver probes), clk_get_rate() dereferences
that error pointer instead of returning 0, crashing instead of letting
probe defer.

Capture the clock in the existing 'clk' local and check it with
IS_ERR() before calling clk_get_rate(), matching the handling already
used for the "rtc" clock in this same function.

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