Re: [PATCH] s390/zcrypt: Switch to flexible array member

[Vasily Gorbik]

On Wed, Jun 16, 2021 at 01:19:02PM -0700, Kees Cook wrote:
> In preparation for FORTIFY_SOURCE performing compile-time and run-time
> field bounds checking for memcpy(), memmove(), and memset(), avoid
> intentionally reading/writing across neighboring array fields.
> 
> Switch from zero-element arrays to flexible arrays so the compiler will
> perform appropriate bounds checking, avoiding these future warnings:
> 
> In function '__fortify_memcpy',
>     inlined from 'cca_sec2protkey' at drivers/s390/crypto/zcrypt_ccamisc.c:645:2:
> ./include/linux/fortify-string.h:244:4: error: call to '__write_overflow_field' declared with attribute error: detected write beyond size of field (1st parameter)
> 
> In function '__fortify_memcpy',
>     inlined from 'cca_clr2seckey' at drivers/s390/crypto/zcrypt_ccamisc.c:568:3:
> ./include/linux/fortify-string.h:246:4: error: call to '__read_overflow2_field' declared with attribute error: detected read beyond size of field (2nd parameter)
> 
> In function '__fortify_memcpy',
>     inlined from 'cca_genseckey' at drivers/s390/crypto/zcrypt_ccamisc.c:429:2:
> ./include/linux/fortify-string.h:246:4: error: call to '__read_overflow2_field' declared with attribute error: detected read beyond size of field (2nd parameter)
> 
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
>  drivers/s390/crypto/zcrypt_ccamisc.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

Applied, thanks!