Re: [PATCH] s390: iucv: Avoid field over-reading memcpy()

[Heiko Carstens]

On Wed, Jun 16, 2021 at 01:19:42PM -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 across neighboring array fields.
> 
> Add a wrapping struct to serve as the memcpy() source so the compiler
> can perform appropriate bounds checking, avoiding this future warning:
> 
> In function '__fortify_memcpy',
>     inlined from 'iucv_message_pending' at net/iucv/iucv.c:1663:4:
> ./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>
> ---
>  net/iucv/iucv.c | 22 ++++++++++++----------
>  1 file changed, 12 insertions(+), 10 deletions(-)

This one is for Julian Wiedmann and Karsten Graul.