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

From: Larry Finger
Date: Tue Jul 27 2021 - 18:30:55 EST


On 7/27/21 3:57 PM, 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@xxxxxxxxxxxx>

Tested-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Acked-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

Looks good.

Larry