On Fri, 2023-10-06 at 13:17 -0700, Kees Cook wrote: > > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for > array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct > rtw89_btc_btf_set_slot_table. > > Cc: Ping-Ke Shih <pkshih@xxxxxxxxxxx> > Cc: Kalle Valo <kvalo@xxxxxxxxxx> > Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx> > Cc: linux-wireless@xxxxxxxxxxxxxxx > Cc: linux-hardening@xxxxxxxxxxxxxxx > Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > --- > drivers/net/wireless/realtek/rtw89/coex.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/wireless/realtek/rtw89/coex.c b/drivers/net/wireless/realtek/rtw89/coex.c > index 4ba8b3df70ae..d66a1152c3f5 100644 > --- a/drivers/net/wireless/realtek/rtw89/coex.c > +++ b/drivers/net/wireless/realtek/rtw89/coex.c > @@ -237,7 +237,7 @@ struct rtw89_btc_btf_set_report { > struct rtw89_btc_btf_set_slot_table { > u8 fver; > u8 tbl_num; > - u8 buf[]; > + u8 buf[] __counted_by(tbl_num); This struct isn't defined properly. It should be struct rtw89_btc_btf_set_slot_table { u8 fver; u8 tbl_num; struct rtw89_btc_fbtc_slot tbl[] __counted_by(tbl_num); } __packed; And, we should modify rtw89_btc_fw_set_slots() as well. Another struct 'rtw89_btc_btf_set_mon_reg' has similar problem. So, NACK this patch. I will prepare one or two patches for them next week. By the way, I have question about __counted_by(). Can I apply it to little/big- endian 'num'? Like struct foo { ... __le32 num; __le32 data[] __counted_by(num); } > } __packed; > > struct rtw89_btc_btf_set_mon_reg { > -- > 2.34.1 >
