On 2/2/22 14:11, Kees Cook wrote:
On Wed, Feb 02, 2022 at 08:09:03AM -0800, Guenter Roeck wrote:
On Wed, Aug 18, 2021 at 01:11:17AM -0700, Kees Cook wrote:
With the recent fixes for flexible arrays and expanded FORTIFY_SOURCE
coverage, it is now possible to enable -Warray-bounds. Since both
GCC and Clang include -Warray-bounds in -Wall, we just need to stop
disabling it.
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: linux-kbuild@xxxxxxxxxxxxxxx
Co-developed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
Makefile | 1 -
1 file changed, 1 deletion(-)
diff --git a/Makefile b/Makefile
index a4aca01a4835..af22b83cede7 100644
--- a/Makefile
+++ b/Makefile
@@ -1072,7 +1072,6 @@ KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
# We'll want to enable this eventually, but it's not going away for 5.7 at least
KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
-KBUILD_CFLAGS += -Wno-array-bounds
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
# Another good warning that we'll want to enable eventually
alpha:defconfig:
In function '__memset',
inlined from '__bad_pagetable' at arch/alpha/mm/init.c:79:2:
./arch/alpha/include/asm/string.h:37:32: error: '__builtin_memset' offset [0, 8191] is out of the bounds [0, 0] [-Werror=array-bounds]
37 | return __builtin_memset(s, c, n);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
In function '__memset',
inlined from '__bad_page' at arch/alpha/mm/init.c:86:2:
./arch/alpha/include/asm/string.h:37:32: error: '__builtin_memset' offset [0, 8191] is out of the bounds [0, 0] [-Werror=array-bounds]
37 | return __builtin_memset(s, c, n);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
In function '__memset',
inlined from 'paging_init' at arch/alpha/mm/init.c:256:2:
./arch/alpha/include/asm/string.h:37:32: error: '__builtin_memset' offset [0, 8191] is out of the bounds [0, 0] [-Werror=array-bounds]
37 | return __builtin_memset(s, c, n);
Ah! With Arnd and Nathan's help, I saw:
https://lore.kernel.org/all/20210912160149.2227137-3-linux@xxxxxxxxxxxx/
Guilty as charged. Sorry, I didn't try to analyze the problem,
or I might have noticed (and saved you some work).
Guenter
which is solving the same problem (just manifested through different
diagnostics). The same solution works here. I'll get the patches sent...
