Re: [PATCH] x86/boot: Reject truncated acpi_rsdp= values

[Borislav Petkov]

On Wed, Jun 17, 2026 at 03:04:18PM +0200, Thorsten Blum wrote:
> cmdline_find_option() returns the full length of the argument value even
> if it is truncated. However, get_cmdline_acpi_rsdp() only checks whether
> acpi_rsdp= is present and does not reject truncated values that do not
> fit in the buffer.
> 
> Reject truncated values early to prevent boot_kstrtoul() from parsing a
> partial value and thus from silently using the wrong RSDP address.

And?

If it uses the wrong address, it'll crash'n'burn later. As it should be.

Or are we protecting people from shooting themselves in foot now too?

-- 
Regards/Gruss,
    Boris.

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