On Thu, Aug 27, 2020 at 12:02:12PM -0700, Linus Torvalds wrote: > On Thu, Aug 27, 2020 at 11:42 AM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > > > Do you mean you checked both gcc and clang and it was only a problem with gcc? > > I didn't check with clang, but Arnd claimed it was fine. > > > (If so, I can tweak the "depends" below...) > > Ugh. > > Instead of making the Makefile even uglier, why don't you just make > this all be done in the Kconfig. > > Also, I'm not seeing the point of your patch. You didn't actually > change anything, you just made a new config variable with the same > semantics as the old one. Hmm? Yeah it did: it disallowed CONFIG_COMPILE_TEST, which you said was the missing piece, I thought? (It's hardly the first time COMPILE_TEST has collided unhappily with *SAN-ish things.) > All of this should be thrown out, and this code should use the proper > patterns for configuration entries in the Makefile, ie just > > ubsan-cflags-$(CONFIG_UBSAN_OBJECT_SIZE) += -fsanitize=object-size Yeah, that would be a better pattern for sure. > and the Kconfig file is the thing that should check if that CC option > exists with > > config UBSAN_OBJECT_SIZE > bool "Check for accesses beyond known object sizes" > default UBSAN > depends on CLANG # gcc makes a mess of it > depends on $(cc-option,-fsanitize-coverage=trace-pc) Yup, for sure. I've only recently started poking at the ubsan stuff. I can clean it up better. > Doesn't that all look much cleaner? Yup! -- Kees Cook
