Re: [PATCH] clk: samsung: exynos-clkout: Assign .num before accessing .hws

[Krzysztof Kozlowski]

On 24/11/2025 20:11, Nathan Chancellor wrote:
> 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.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by")
> Reported-by: Jochen Sprickerhof <jochen@xxxxxxxxxxxxxx>
> Closes: https://lore.kernel.org/aSIYDN5eyKFKoXKL@xxxxxxxxxxx/
> Tested-by: Jochen Sprickerhof <jochen@xxxxxxxxxxxxxx>
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>

@Stephen,

Can you take this directly? You already pulled from me for next cycle,
so that way might be easier.

The fixed commit is from 2023, so does not really fit criteria for late
RC fixes, thus I propose for next release.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>

Best regards,
Krzysztof