On Thu, Mar 28, 2024 at 02:55:05PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@xxxxxxxx> > > gcc-9 and some other older versions produce a false-positive warning > for zeroing two fields > > In file included from include/linux/string.h:369, > from drivers/net/wireless/ath/ath9k/main.c:18: > In function 'fortify_memset_chk', > inlined from 'ath9k_ps_wakeup' at drivers/net/wireless/ath/ath9k/main.c:140:3: > include/linux/fortify-string.h:462:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning] > 462 | __write_overflow_field(p_size_field, size); > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Using a struct_group seems to reliably avoid the warning and > not make the code much uglier. The combined memset() should even > save a couple of cpu cycles. > > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> -- Kees Cook
