| Message ID | 20220907234345.96798-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | sh: machvec: Use char[] for section boundaries | expand |
On Thu, Sep 8, 2022 at 1:43 AM Kees Cook <keescook@chromium.org> wrote: > As done for other sections, define the extern as a character array, > which relaxes many of the compiler-time object size checks, which would > otherwise assume it's a single long. Solves the following build error: > > arch/sh/kernel/machvec.c: error: array subscript 'struct sh_machine_vector[0]' is partly outside array bounds of 'long int[1]' [-Werror=array-bounds]: => 105:33 > > Cc: Yoshinori Sato <ysato@users.sourceforge.jp> > Cc: Rich Felker <dalias@libc.org> > Cc: linux-sh@vger.kernel.org > Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> > Link: https://lore.kernel.org/lkml/alpine.DEB.2.22.394.2209050944290.964530@ramsan.of.borg/ > Fixes: 9655ad03af2d ("sh: Fixup machvec support.") > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
On Wed, Sep 07, 2022 at 04:43:45PM -0700, Kees Cook wrote: > As done for other sections, define the extern as a character array, > which relaxes many of the compiler-time object size checks, which would > otherwise assume it's a single long. Solves the following build error: > > arch/sh/kernel/machvec.c: error: array subscript 'struct sh_machine_vector[0]' is partly outside array bounds of 'long int[1]' [-Werror=array-bounds]: => 105:33 > > Cc: Yoshinori Sato <ysato@users.sourceforge.jp> > Cc: Rich Felker <dalias@libc.org> > Cc: linux-sh@vger.kernel.org > Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> > Link: https://lore.kernel.org/lkml/alpine.DEB.2.22.394.2209050944290.964530@ramsan.of.borg/ > Fixes: 9655ad03af2d ("sh: Fixup machvec support.") > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks -- Gustavo
On Wed, Sep 07, 2022 at 04:43:45PM -0700, Kees Cook wrote: > As done for other sections, define the extern as a character array, > which relaxes many of the compiler-time object size checks, which would > otherwise assume it's a single long. Solves the following build error: > > arch/sh/kernel/machvec.c: error: array subscript 'struct sh_machine_vector[0]' is partly outside array bounds of 'long int[1]' [-Werror=array-bounds]: => 105:33 LGMT. This is the approach I recommend for this general type of mechanism. So, Acked-by: Rich Felker <dalias@libc.org> Since I haven't been on top of collating patches for upstreaming, I'd be happy if anyone else wants to take this in their tree before I get back to it. Rich > Cc: Yoshinori Sato <ysato@users.sourceforge.jp> > Cc: Rich Felker <dalias@libc.org> > Cc: linux-sh@vger.kernel.org > Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> > Link: https://lore.kernel.org/lkml/alpine.DEB.2.22.394.2209050944290.964530@ramsan.of.borg/ > Fixes: 9655ad03af2d ("sh: Fixup machvec support.") > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > arch/sh/include/asm/sections.h | 2 +- > arch/sh/kernel/machvec.c | 10 +++++----- > 2 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/arch/sh/include/asm/sections.h b/arch/sh/include/asm/sections.h > index 8edb824049b9..0cb0ca149ac3 100644 > --- a/arch/sh/include/asm/sections.h > +++ b/arch/sh/include/asm/sections.h > @@ -4,7 +4,7 @@ > > #include <asm-generic/sections.h> > > -extern long __machvec_start, __machvec_end; > +extern char __machvec_start[], __machvec_end[]; > extern char __uncached_start, __uncached_end; > extern char __start_eh_frame[], __stop_eh_frame[]; > > diff --git a/arch/sh/kernel/machvec.c b/arch/sh/kernel/machvec.c > index d606679a211e..57efaf5b82ae 100644 > --- a/arch/sh/kernel/machvec.c > +++ b/arch/sh/kernel/machvec.c > @@ -20,8 +20,8 @@ > #define MV_NAME_SIZE 32 > > #define for_each_mv(mv) \ > - for ((mv) = (struct sh_machine_vector *)&__machvec_start; \ > - (mv) && (unsigned long)(mv) < (unsigned long)&__machvec_end; \ > + for ((mv) = (struct sh_machine_vector *)__machvec_start; \ > + (mv) && (unsigned long)(mv) < (unsigned long)__machvec_end; \ > (mv)++) > > static struct sh_machine_vector * __init get_mv_byname(const char *name) > @@ -87,8 +87,8 @@ void __init sh_mv_setup(void) > if (!machvec_selected) { > unsigned long machvec_size; > > - machvec_size = ((unsigned long)&__machvec_end - > - (unsigned long)&__machvec_start); > + machvec_size = ((unsigned long)__machvec_end - > + (unsigned long)__machvec_start); > > /* > * Sanity check for machvec section alignment. Ensure > @@ -102,7 +102,7 @@ void __init sh_mv_setup(void) > * vector (usually the only one) from .machvec.init. > */ > if (machvec_size >= sizeof(struct sh_machine_vector)) > - sh_mv = *(struct sh_machine_vector *)&__machvec_start; > + sh_mv = *(struct sh_machine_vector *)__machvec_start; > } > > pr_notice("Booting machvec: %s\n", get_system_type()); > -- > 2.34.1
On Thu, Sep 08, 2022 at 06:15:39PM -0400, Rich Felker wrote: > On Wed, Sep 07, 2022 at 04:43:45PM -0700, Kees Cook wrote: > > As done for other sections, define the extern as a character array, > > which relaxes many of the compiler-time object size checks, which would > > otherwise assume it's a single long. Solves the following build error: > > > > arch/sh/kernel/machvec.c: error: array subscript 'struct sh_machine_vector[0]' is partly outside array bounds of 'long int[1]' [-Werror=array-bounds]: => 105:33 > > LGMT. This is the approach I recommend for this general type of > mechanism. So, > > Acked-by: Rich Felker <dalias@libc.org> > > Since I haven't been on top of collating patches for upstreaming, I'd > be happy if anyone else wants to take this in their tree before I get > back to it. Great; thanks! I'll take it via my tree. :) -Kees
diff --git a/arch/sh/include/asm/sections.h b/arch/sh/include/asm/sections.h index 8edb824049b9..0cb0ca149ac3 100644 --- a/arch/sh/include/asm/sections.h +++ b/arch/sh/include/asm/sections.h @@ -4,7 +4,7 @@ #include <asm-generic/sections.h> -extern long __machvec_start, __machvec_end; +extern char __machvec_start[], __machvec_end[]; extern char __uncached_start, __uncached_end; extern char __start_eh_frame[], __stop_eh_frame[]; diff --git a/arch/sh/kernel/machvec.c b/arch/sh/kernel/machvec.c index d606679a211e..57efaf5b82ae 100644 --- a/arch/sh/kernel/machvec.c +++ b/arch/sh/kernel/machvec.c @@ -20,8 +20,8 @@ #define MV_NAME_SIZE 32 #define for_each_mv(mv) \ - for ((mv) = (struct sh_machine_vector *)&__machvec_start; \ - (mv) && (unsigned long)(mv) < (unsigned long)&__machvec_end; \ + for ((mv) = (struct sh_machine_vector *)__machvec_start; \ + (mv) && (unsigned long)(mv) < (unsigned long)__machvec_end; \ (mv)++) static struct sh_machine_vector * __init get_mv_byname(const char *name) @@ -87,8 +87,8 @@ void __init sh_mv_setup(void) if (!machvec_selected) { unsigned long machvec_size; - machvec_size = ((unsigned long)&__machvec_end - - (unsigned long)&__machvec_start); + machvec_size = ((unsigned long)__machvec_end - + (unsigned long)__machvec_start); /* * Sanity check for machvec section alignment. Ensure @@ -102,7 +102,7 @@ void __init sh_mv_setup(void) * vector (usually the only one) from .machvec.init. */ if (machvec_size >= sizeof(struct sh_machine_vector)) - sh_mv = *(struct sh_machine_vector *)&__machvec_start; + sh_mv = *(struct sh_machine_vector *)__machvec_start; } pr_notice("Booting machvec: %s\n", get_system_type());
As done for other sections, define the extern as a character array, which relaxes many of the compiler-time object size checks, which would otherwise assume it's a single long. Solves the following build error: arch/sh/kernel/machvec.c: error: array subscript 'struct sh_machine_vector[0]' is partly outside array bounds of 'long int[1]' [-Werror=array-bounds]: => 105:33 Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: linux-sh@vger.kernel.org Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/lkml/alpine.DEB.2.22.394.2209050944290.964530@ramsan.of.borg/ Fixes: 9655ad03af2d ("sh: Fixup machvec support.") Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/sh/include/asm/sections.h | 2 +- arch/sh/kernel/machvec.c | 10 +++++----- 2 files changed, 6 insertions(+), 6 deletions(-)