RE: [PATCH 23/32] ACPICA: struct acpi_nfit_interleave: Replace 1-element array with flexible array

Dan Williams
2023-04-06T00:37:23Z

Rafael J. Wysocki wrote:
> From: Kees Cook <kees@outflux.net>
>
> ACPICA commit e66decc6fca36b59194b0947d87d6a9bec078bc3
>
> Similar to "Replace one-element array with flexible-array", replace the
> 1-element array with a proper flexible array member as defined by C99.
>
> This allows the code to operate without tripping compile-time and run-
> time bounds checkers (e.g. via __builtin_object_size(), -fsanitize=bounds,
> and/or -fstrict-flex-arrays=3).
>
> Unlike struct acpi_nfit_flush_address and struct acpi_nfit_smbios, which
> had their sizeof() uses adjusted in code, struct acpi_nfit_interleave did
> not. This appears to have been a bug. After this change, there is a binary
> difference in acpi_dm_dump_nfit() since the size of the structure now has
> the correct size, as the prior result was including the trailing U32:
>
> - mov $0x14,%ebp
> + mov $0x10,%ebp
>
> Link: https://github.com/acpica/acpica/commit/e66decc6
> Signed-off-by: Bob Moore <robert.moore@intel.com>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>