On Tue, Feb 07, 2023 at 10:01:21AM -0800, Nick Desaulniers wrote:
On Mon, Feb 6, 2023 at 3:41 PM Fangrui Song maskray@google.com wrote:
On Sat, Feb 4, 2023 at 11:06 AM Kees Cook keescook@chromium.org wrote:
On Fri, Feb 03, 2023 at 11:42:01AM -0800, Eric Biggers wrote:
From: Eric Biggers ebiggers@google.com
Randstruct with clang is currently unsafe to use in any clang release that supports it, due to a clang bug that is causing miscompilations: "-frandomize-layout-seed inconsistently randomizes all-function-pointers structs" (https://github.com/llvm/llvm-project/issues/60349). Disable it temporarily until the bug is fixed and the fix is released in a clang version that can be checked for.
Fixes: 035f7f87b729 ("randstruct: Enable Clang support") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers ebiggers@google.com
security/Kconfig.hardening | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening index 53baa95cb644..aad16187148c 100644 --- a/security/Kconfig.hardening +++ b/security/Kconfig.hardening @@ -280,7 +280,8 @@ config ZERO_CALL_USED_REGS endmenu
config CC_HAS_RANDSTRUCT
def_bool $(cc-option,-frandomize-layout-seed-file=/dev/null)
# Temporarily disabled due to https://github.com/llvm/llvm-project/issues/60349def_bool nchoice prompt "Randomize layout of sensitive kernel structures"
base-commit: 7b753a909f426f2789d9db6f357c3d59180a9354
2.39.1
This should be fixed with greater precision -- i.e. this is nearly fixed in Clang now, and is likely to be backported. So I think we'll need versioned checks here.
-- Kees Cook
Bill has requested cherry-pick the llvm-project fix into the release/16.x branch [1]. https://github.com/llvm/llvm-project-release-prs/pull/276 It may take one day to land.
-- 宋方睿
All landed; the version check should be for 16+. (And the link to the issue report would be nice to retain).
Thanks! Done in "[PATCH] randstruct: disable Clang 15 support" (https://lore.kernel.org/linux-hardening/20230208065133.220589-1-ebiggers@ker...).
- Eric