From 11bb1678e249e51cd748e8f91e5241b3ce71da3a Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sat, 3 May 2025 11:46:20 -0700 Subject: [PATCH] integer-wrap: Force full rebuild when .scl file changes Since the integer wrapping sanitizer's behavior depends on its associated .scl file, we must force a full rebuild if the file changes. If not, instrumentation may differ between targets based on when they were built. Generate a new header file, integer-wrap.h, any time the Clang .scl file changes. Include the header file in compiler-version.h when its associated feature name, INTEGER_WRAP, is defined. This will be picked up by fixdep and force rebuilds where needed. Acked-by: Justin Stitt Link: https://lore.kernel.org/r/20250503184623.2572355-3-kees@kernel.org Reviewed-by: Nicolas Schier Signed-off-by: Kees Cook --- include/linux/compiler-version.h | 10 ++++++++++ scripts/Makefile.ubsan | 1 + scripts/basic/Makefile | 5 +++++ 3 files changed, 16 insertions(+) diff --git a/include/linux/compiler-version.h b/include/linux/compiler-version.h index 4b9d39b37650..ac1665a98a15 100644 --- a/include/linux/compiler-version.h +++ b/include/linux/compiler-version.h @@ -32,3 +32,13 @@ #ifdef RANDSTRUCT #include #endif + +/* + * If any external changes affect Clang's integer wrapping sanitizer + * behavior, a full rebuild is needed as the coverage for wrapping types + * may have changed, which may impact the expected behaviors that should + * not differ between compilation units. + */ +#ifdef INTEGER_WRAP +#include +#endif diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan index 9e35198edbf0..653f7117819c 100644 --- a/scripts/Makefile.ubsan +++ b/scripts/Makefile.ubsan @@ -15,6 +15,7 @@ ubsan-cflags-$(CONFIG_UBSAN_TRAP) += $(call cc-option,-fsanitize-trap=undefined export CFLAGS_UBSAN := $(ubsan-cflags-y) ubsan-integer-wrap-cflags-$(CONFIG_UBSAN_INTEGER_WRAP) += \ + -DINTEGER_WRAP \ -fsanitize-undefined-ignore-overflow-pattern=all \ -fsanitize=signed-integer-overflow \ -fsanitize=unsigned-integer-overflow \ diff --git a/scripts/basic/Makefile b/scripts/basic/Makefile index dd289a6725ac..fb8e2c38fbc7 100644 --- a/scripts/basic/Makefile +++ b/scripts/basic/Makefile @@ -14,3 +14,8 @@ cmd_create_randstruct_seed = \ $(obj)/randstruct.seed: $(gen-randstruct-seed) FORCE $(call if_changed,create_randstruct_seed) always-$(CONFIG_RANDSTRUCT) += randstruct.seed + +# integer-wrap: if the .scl file changes, we need to do a full rebuild. +$(obj)/../../include/generated/integer-wrap.h: $(srctree)/scripts/integer-wrap-ignore.scl FORCE + $(call if_changed,touch) +always-$(CONFIG_UBSAN_INTEGER_WRAP) += ../../include/generated/integer-wrap.h -- 2.50.1