hardening: Disable GCC randstruct for COMPILE_TEST

[PATCH] hardening: Disable GCC randstruct for COMPILE_TEST

Posted by Kees Cook 2 weeks, 6 days ago

There is a GCC crash bug in the randstruct for latest GCC versions that
is being tickled by landlock[1]. Temporarily disable GCC randstruct for
COMPILE_TEST builds to unbreak CI systems for the coming -rc2. This can
be restored once the bug is fixed.

Suggested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/all/20250407-kbuild-disable-gcc-plugins-v1-1-5d46ae583f5e@kernel.org/ [1]
Signed-off-by: Kees Cook <kees@kernel.org>
---
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-hardening@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
---
 security/Kconfig.hardening | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening
index c17366ce8224..3fe9d7b945c4 100644
--- a/security/Kconfig.hardening
+++ b/security/Kconfig.hardening
@@ -344,7 +344,7 @@ config CC_HAS_RANDSTRUCT
 
 choice
 	prompt "Randomize layout of sensitive kernel structures"
-	default RANDSTRUCT_FULL if COMPILE_TEST && (GCC_PLUGINS || CC_HAS_RANDSTRUCT)
+	default RANDSTRUCT_FULL if COMPILE_TEST && CC_HAS_RANDSTRUCT
 	default RANDSTRUCT_NONE
 	help
 	  If you enable this, the layouts of structures that are entirely
-- 
2.34.1

Re: [PATCH] hardening: Disable GCC randstruct for COMPILE_TEST

Posted by Mark Brown 2 weeks, 6 days ago

On Wed, Apr 09, 2025 at 08:11:58AM -0700, Kees Cook wrote:
> There is a GCC crash bug in the randstruct for latest GCC versions that
> is being tickled by landlock[1]. Temporarily disable GCC randstruct for
> COMPILE_TEST builds to unbreak CI systems for the coming -rc2. This can
> be restored once the bug is fixed.

Acked-by: Mark Brown <broonie@kernel.org>

Re: [PATCH] hardening: Disable GCC randstruct for COMPILE_TEST

Posted by Arnd Bergmann 2 weeks, 6 days ago

On Wed, Apr 9, 2025, at 17:11, Kees Cook wrote:
> There is a GCC crash bug in the randstruct for latest GCC versions that
> is being tickled by landlock[1]. Temporarily disable GCC randstruct for
> COMPILE_TEST builds to unbreak CI systems for the coming -rc2. This can
> be restored once the bug is fixed.
>
> Suggested-by: Mark Brown <broonie@kernel.org>
> Link: 
> https://lore.kernel.org/all/20250407-kbuild-disable-gcc-plugins-v1-1-5d46ae583f5e@kernel.org/ 
> [1]
> Signed-off-by: Kees Cook <kees@kernel.org>

Acked-by: Arnd Bergmann <arnd@arndb.de>