[PATCH 0/3 v2] staging: rtl*: Check for NULL header value

[Kees Cook <keescook@chromium.org>]

Hi,

When building with -Warray-bounds, the following warning is emitted:

In file included from ./include/linux/string.h:253,
                 from ./arch/x86/include/asm/page_32.h:22,
                 from ./arch/x86/include/asm/page.h:14,
                 from ./arch/x86/include/asm/thread_info.h:12,
                 from ./include/linux/thread_info.h:60,
                 from ./arch/x86/include/asm/preempt.h:7,
                 from ./include/linux/preempt.h:78,
                 from ./include/linux/rcupdate.h:27,
                 from ./include/linux/rculist.h:11,
                 from ./include/linux/sched/signal.h:5,
                 from ./drivers/staging/rtl8723bs/include/drv_types.h:17,
                 from drivers/staging/rtl8723bs/core/rtw_recv.c:7:
In function 'memcpy',
    inlined from 'wlanhdr_to_ethhdr' at drivers/staging/rtl8723bs/core/rtw_recv.c:1554:2:
./include/linux/fortify-string.h:41:33: warning: '__builtin_memcpy' offset [0, 5] is out of the bounds [0, 0] [-Warray-bounds]
   41 | #define __underlying_memcpy     __builtin_memcpy
      |                                 ^

This is due to various paths to the memcpy() where the compile could
see the destination buffer having a NULL value. This series fixes this
by both eliminating cases where NULL returns were impossible and adding
missing NULL checks where values were possible.

Thanks!

-Kees

v1: https://lore.kernel.org/lkml/20220113002001.3498383-1-keescook@chromium.org/
v2:
 - drop get_recvframe_data()
 - add missing NULL checks to r8188eu and rtl8723bs (already present in rtl8712)

Kees Cook (3):
  staging: r8188eu: Drop get_recvframe_data()
  staging: rtl8723bs: Drop get_recvframe_data()
  staging: rtl8712: Drop get_recvframe_data()

 drivers/staging/r8188eu/core/rtw_recv.c        |  6 +++++-
 drivers/staging/r8188eu/hal/rtl8188e_rxdesc.c  |  4 +---
 drivers/staging/r8188eu/include/rtw_recv.h     |  9 ---------
 drivers/staging/rtl8712/rtl871x_recv.c         |  4 ++--
 drivers/staging/rtl8712/rtl871x_recv.h         |  8 --------
 drivers/staging/rtl8723bs/core/rtw_recv.c      | 11 ++++++++---
 drivers/staging/rtl8723bs/hal/rtl8723bs_recv.c |  3 +--
 drivers/staging/rtl8723bs/include/rtw_recv.h   | 11 -----------
 8 files changed, 17 insertions(+), 39 deletions(-)

-- 
2.30.2