Re: [PATCH 07/64] staging: rtl8192e: Use struct_group() for memcpy() region

Greg Kroah-Hartman
2021-07-28T05:45:45Z

On Tue, Jul 27, 2021 at 01:57:58PM -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 writing across neighboring fields.
>
> Use struct_group() around members addr1, addr2, and addr3 in struct
> rtllib_hdr_4addr, and members qui, qui_type, qui_subtype, version,
> and ac_info in struct rtllib_qos_information_element, so they can be
> referenced together. This will allow memcpy() and sizeof() to more easily
> reason about sizes, improve readability, and avoid future warnings about
> writing beyond the end of addr1 and qui.
>
> "pahole" shows no size nor member offset changes to struct
> rtllib_hdr_4addr nor struct rtllib_qos_information_element. "objdump -d"
> shows no meaningful object code changes (i.e. only source line number
> induced differences and optimizations).
>
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
> drivers/staging/rtl8192e/rtllib.h | 20 ++++++++++++--------
> drivers/staging/rtl8192e/rtllib_crypt_ccmp.c | 3 ++-
> drivers/staging/rtl8192e/rtllib_rx.c | 8 ++++----
> 3 files changed, 18 insertions(+), 13 deletions(-)

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>