* Re: Build regressions/improvements in v6.0-rc4
2022-09-05 7:46 ` Build regressions/improvements in v6.0-rc4 Geert Uytterhoeven
@ 2022-09-06 21:42 ` Kees Cook
2022-09-07 23:47 ` Kees Cook
1 sibling, 0 replies; 3+ messages in thread
From: Kees Cook @ 2022-09-06 21:42 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: linux-kernel, linux-sh, amd-gfx, linux-s390, linux-hardening
On Mon, Sep 05, 2022 at 09:46:01AM +0200, Geert Uytterhoeven wrote:
> On Mon, 5 Sep 2022, Geert Uytterhoeven wrote:
> > JFYI, when comparing v6.0-rc4[1] to v6.0-rc3[3], the summaries are:
> > - build errors: +3/-16
>
> + /kisskb/src/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
>
> sh4-gcc11/sh-allyesconfig (-Werror)
Interesting -- I wonder why this suddenly appeared. I think the fix is
the common "linker addresses need to be char arrays" fix:
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());
>
> + /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.c: error: the frame size of 2144 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]: => 3768:1
>
> x86_64-gcc8/x86-allmodconfig (in function dml32_ModeSupportAndSystemConfigurationFull())
This I don't know about it, but looks like a recent commit: dda4fb85e433f
Given it's a 2000 line function, I assume it could be improved! :)
> + /kisskb/src/include/linux/fortify-string.h: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]: => 258:25
>
> s390x-gcc11/s390-allyesconfig (inlined from 'copy_process' at /kisskb/src/kernel/fork.c:2200:2)
This is:
memset(&p->irqtrace, 0, sizeof(p->irqtrace));
p->irqtrace is:
struct irqtrace_events irqtrace;
But that's a whole object destination... why would only s390 warn?
-Kees
--
Kees Cook
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: Build regressions/improvements in v6.0-rc4
2022-09-05 7:46 ` Build regressions/improvements in v6.0-rc4 Geert Uytterhoeven
2022-09-06 21:42 ` Kees Cook
@ 2022-09-07 23:47 ` Kees Cook
1 sibling, 0 replies; 3+ messages in thread
From: Kees Cook @ 2022-09-07 23:47 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: linux-kernel, linux-sh, amd-gfx, linux-s390, linux-hardening
On Mon, Sep 05, 2022 at 09:46:01AM +0200, Geert Uytterhoeven wrote:
> On Mon, 5 Sep 2022, Geert Uytterhoeven wrote:
> > JFYI, when comparing v6.0-rc4[1] to v6.0-rc3[3], the summaries are:
> > - build errors: +3/-16
>
> + /kisskb/src/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
>
> sh4-gcc11/sh-allyesconfig (-Werror)
Sent a patch for this:
https://lore.kernel.org/linux-hardening/20220907234345.96798-1-keescook@chromium.org/
> + /kisskb/src/include/linux/fortify-string.h: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]: => 258:25
>
> s390x-gcc11/s390-allyesconfig (inlined from 'copy_process' at /kisskb/src/kernel/fork.c:2200:2)
This error appears to have vanished?
> > [3] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/b90cb1053190353cc30f0fef0ef1f378ccc063c5/ (all 135 configs)
Status Date/time Target
OK Sep 7, 13:54 linus/s390-allyesconfig/s390x-gcc11
--
Kees Cook
^ permalink raw reply [flat|nested] 3+ messages in thread