# CVE-2025-71143: clk: samsung: exynos-clkout: Assign .num before accessing .hws

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-01-14 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 6.6

## Description

In the Linux kernel, the following vulnerability has been resolved: clk: samsung: exynos-clkout: Assign .num before accessing .hws Commit f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by") annotated the hws member of 'struct clk_hw_onecell_data' with __counted_by, which informs the bounds sanitizer (UBSAN_BOUNDS) about the number of elements in .hws[], so that it can warn when .hws[] is accessed out of bounds. As noted in that change, the __counted_by member must be initialized with the number of elements before the first array access happens, otherwise there will be a warning from each access prior to the initialization because the number of elements is zero. This occurs in exynos_clkout_probe() due to .num being assigned after .hws[] has been accessed: UBSAN: array-index-out-of-bounds in drivers/clk/samsung/clk-exynos-clkout.c:178:18 index 0 is out of range for type 'clk_hw *[*]' Move the .num initialization to before the first access of .hws[], clearing up the warning.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
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  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-71143

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/fbf57f5e453dadadb3d29b2d1dbe067e3dc4e236
- https://git.kernel.org/stable/c/eb1f3a6ab3efee2b52361879cdc2dc6b11f499c0
- https://git.kernel.org/stable/c/a317f63255ebc3dac378c79c5bff4f8d0561c290
- https://git.kernel.org/stable/c/cf33f0b7df13685234ccea7be7bfe316b60db4db

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Page: https://cve.now/CVE-2025-71143
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