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 <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: [email protected]
Reported-by: Geert Uytterhoeven <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Fixes: 9655ad03af2d ("sh: Fixup machvec support.")
Signed-off-by: Kees Cook <[email protected]>
---
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 8, 2022 at 1:43 AM Kees Cook <[email protected]> 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 <[email protected]>
> Cc: Rich Felker <[email protected]>
> Cc: [email protected]
> Reported-by: Geert Uytterhoeven <[email protected]>
> Link: https://lore.kernel.org/lkml/[email protected]/
> Fixes: 9655ad03af2d ("sh: Fixup machvec support.")
> Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Geert Uytterhoeven <[email protected]>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
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 <[email protected]>
> Cc: Rich Felker <[email protected]>
> Cc: [email protected]
> Reported-by: Geert Uytterhoeven <[email protected]>
> Link: https://lore.kernel.org/lkml/[email protected]/
> Fixes: 9655ad03af2d ("sh: Fixup machvec support.")
> Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
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 <[email protected]>
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 <[email protected]>
> Cc: Rich Felker <[email protected]>
> Cc: [email protected]
> Reported-by: Geert Uytterhoeven <[email protected]>
> Link: https://lore.kernel.org/lkml/[email protected]/
> Fixes: 9655ad03af2d ("sh: Fixup machvec support.")
> Signed-off-by: Kees Cook <[email protected]>
> ---
> 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 <[email protected]>
>
> 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
--
Kees Cook