Re: [PATCH] crypto: qat - avoid memcpy() overflow warning

[Cabiddu, Giovanni]

On Wed, Jan 03, 2024 at 05:26:02PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> The use of array_size() leads gcc to assume the memcpy() can have a larger
> limit than actually possible, which triggers a string fortification warning:
> 
> In file included from include/linux/string.h:296,
>                  from include/linux/bitmap.h:12,
>                  from include/linux/cpumask.h:12,
>                  from include/linux/sched.h:16,
>                  from include/linux/delay.h:23,
>                  from include/linux/iopoll.h:12,
>                  from drivers/crypto/intel/qat/qat_common/adf_gen4_hw_data.c:3:
> In function 'fortify_memcpy_chk',
>     inlined from 'adf_gen4_init_thd2arb_map' at drivers/crypto/intel/qat/qat_common/adf_gen4_hw_data.c:401:3:
> include/linux/fortify-string.h:579:4: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
>   579 |    __write_overflow_field(p_size_field, size);
>       |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/fortify-string.h:588:4: error: call to '__read_overflow2_field' declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Werror=attribute-warning]
>   588 |    __read_overflow2_field(q_size_field, size);
>       |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> Add an explicit range check to avoid this.
> 
> Fixes: 5da6a2d5353e ("crypto: qat - generate dynamically arbiter mappings")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Acked-by: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx>