From: Eric Biggers <ebiggers@xxxxxxxxxx> commit 78f7a3fd6dc66cb788c21d7705977ed13c879351 upstream. The randstruct support released in Clang 15 is unsafe to use due to a bug that can cause miscompilations: "-frandomize-layout-seed inconsistently randomizes all-function-pointers structs" (https://github.com/llvm/llvm-project/issues/60349). It has been fixed on the Clang 16 release branch, so add a Clang version check. Fixes: 035f7f87b729 ("randstruct: Enable Clang support") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Acked-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx> Reviewed-by: Bill Wendling <morbo@xxxxxxxxxx> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230208065133.220589-1-ebiggers@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- security/Kconfig.hardening | 3 +++ 1 file changed, 3 insertions(+) --- a/security/Kconfig.hardening +++ b/security/Kconfig.hardening @@ -281,6 +281,9 @@ endmenu config CC_HAS_RANDSTRUCT def_bool $(cc-option,-frandomize-layout-seed-file=/dev/null) + # Randstruct was first added in Clang 15, but it isn't safe to use until + # Clang 16 due to https://github.com/llvm/llvm-project/issues/60349 + depends on !CC_IS_CLANG || CLANG_VERSION >= 160000 choice prompt "Randomize layout of sensitive kernel structures"
