Re: [PATCH 2/5] [v2] acpi: disable -Wstringop-truncation

[Rafael J. Wysocki]

On Tue, Apr 9, 2024 at 4:01 PM Arnd Bergmann <arnd@xxxxxxxxxx> wrote:
>
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> gcc -Wstringop-truncation warns about copying a string that results in a
> missing nul termination:
>
> drivers/acpi/acpica/tbfind.c: In function 'acpi_tb_find_table':
> drivers/acpi/acpica/tbfind.c:60:9: error: 'strncpy' specified bound 6 equals destination size [-Werror=stringop-truncation]
>    60 |         strncpy(header.oem_id, oem_id, ACPI_OEM_ID_SIZE);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/acpi/acpica/tbfind.c:61:9: error: 'strncpy' specified bound 8 equals destination size [-Werror=stringop-truncation]
>    61 |         strncpy(header.oem_table_id, oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> The code works as intended, and the warning could be addressed by using
> a memcpy(), but turning the warning off for this file works equally well
> and may be easir to merge.

"easier" (fixed up).

Tricky that, but OK.let's get the warning off the table.

Applied as 6.10 material, thanks!

> Fixes: 47c08729bf1c ("ACPICA: Fix for LoadTable operator, input strings")
> Link: https://lore.kernel.org/lkml/CAJZ5v0hoUfv54KW7y4223Mn9E7D4xvR7whRFNLTBqCZMUxT50Q@xxxxxxxxxxxxxx/#t
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>  drivers/acpi/acpica/Makefile | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/acpi/acpica/Makefile b/drivers/acpi/acpica/Makefile
> index 30f3fc13c29d..8d18af396de9 100644
> --- a/drivers/acpi/acpica/Makefile
> +++ b/drivers/acpi/acpica/Makefile
> @@ -5,6 +5,7 @@
>
>  ccflags-y                      := -D_LINUX -DBUILDING_ACPICA
>  ccflags-$(CONFIG_ACPI_DEBUG)   += -DACPI_DEBUG_OUTPUT
> +CFLAGS_tbfind.o                += $(call cc-disable-warning, stringop-truncation)
>
>  # use acpi.o to put all files here into acpi.o modparam namespace
>  obj-y  += acpi.o
> --
> 2.39.2
>
>