Re: [PATCH v2] ubsan: Tighten UBSAN_BOUNDS on GCC

[Kees Cook]

On Wed, Jun 21, 2023 at 05:50:53PM -0700, Guenter Roeck wrote:
> On 6/21/23 10:52, Kees Cook wrote:
> > On Wed, Jun 21, 2023 at 09:42:01AM -0700, Guenter Roeck wrote:
> > > Hi,
> > > 
> > > On Tue, Apr 04, 2023 at 07:23:59PM -0700, Kees Cook wrote:
> > > > The use of -fsanitize=bounds on GCC will ignore some trailing arrays,
> > > > leaving a gap in coverage. Switch to using -fsanitize=bounds-strict to
> > > > match Clang's stricter behavior.
> > > > 
> > > > Cc: Marco Elver <elver@xxxxxxxxxx>
> > > > Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> > > > Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
> > > > Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> > > > Cc: Nicolas Schier <nicolas@xxxxxxxxx>
> > > > Cc: Tom Rix <trix@xxxxxxxxxx>
> > > > Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> > > > Cc: Miroslav Benes <mbenes@xxxxxxx>
> > > > Cc: linux-kbuild@xxxxxxxxxxxxxxx
> > > > Cc: llvm@xxxxxxxxxxxxxxx
> > > > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> > > > ---
> > > 
> > > This patch, presumably as side effect, enables CONFIG_ARCH_STM32
> > > for arm64:allmodconfig. As consequence, CONFIG_STM32_RPROC is enabled
> > > as well. This in turn results in the following build error.
> > > 
> > > Building arm64:allmodconfig ... failed
> > > --------------
> > > Error log:
> > > In file included from include/linux/printk.h:564,
> > >                   from include/asm-generic/bug.h:22,
> > >                   from arch/arm64/include/asm/bug.h:26,
> > >                   from include/linux/bug.h:5,
> > >                   from include/linux/fortify-string.h:5,
> > >                   from include/linux/string.h:254,
> > >                   from include/linux/dma-mapping.h:7,
> > >                   from drivers/remoteproc/stm32_rproc.c:9:
> > > drivers/remoteproc/stm32_rproc.c: In function 'stm32_rproc_mem_alloc':
> > > drivers/remoteproc/stm32_rproc.c:122:22: error: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'size_t'
> > > 
> > > I did not try to understand what is going on, but reverting this
> > > patch fixes the problem.
> > 
> > Well that is really weird! I will investigate... this patch should be
> > pretty self-contained...
> > 
> Meh, it is. Sorry for the noise. My bisect script was wrong.

Oh, okay; whew! I was really scratching my head. :)

-- 
Kees Cook