[PATCH 2/4] ubsan: Disable object-size sanitizer under GCC

[Kees Cook]

GCC's -fsanitize=object-size (as part of CONFIG_UBSAN_MISC) greatly
increases stack utilization. Do not allow this under GCC.

Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/lkml/CAHk-=wjPasyJrDuwDnpHJS2TuQfExwe=px-SzLeN8GFMAQJPmQ@xxxxxxxxxxxxxx/
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
 lib/Kconfig.ubsan | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan
index c0b801871e0b..aeb2cdea0b94 100644
--- a/lib/Kconfig.ubsan
+++ b/lib/Kconfig.ubsan
@@ -104,6 +104,9 @@ config UBSAN_UNSIGNED_OVERFLOW
 
 config UBSAN_OBJECT_SIZE
 	def_bool UBSAN_MISC
+	# gcc hugely expands stack usage with -fsanitize=object-size
+	# https://lore.kernel.org/lkml/CAHk-=wjPasyJrDuwDnpHJS2TuQfExwe=px-SzLeN8GFMAQJPmQ@xxxxxxxxxxxxxx/
+	depends on !CC_IS_GCC
 	depends on $(cc-option,-fsanitize=object-size)
 
 config UBSAN_BOOL
-- 
2.25.1