Commit ce661672 authored by Jann Horn's avatar Jann Horn Committed by Kees Cook
Browse files

ubsan: Clarify Kconfig text for CONFIG_UBSAN_TRAP 



Make it clearer in the one-line description and the verbose description
text that CONFIG_UBSAN_TRAP as currently implemented involves a tradeoff of
much less helpful oops messages in exchange for a smaller kernel image.
(With the additional effect of turning UBSAN warnings into crashes, which
may or may not be desired.)

Signed-off-by: default avatarJann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20230705215128.486054-1-jannh@google.com


Signed-off-by: default avatarKees Cook <keescook@chromium.org>
parent fdf0eaf1

lib/Kconfig.ubsan

+9 −1
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ menuconfig UBSAN 
if UBSAN



config UBSAN_TRAP

	bool "On Sanitizer warnings, abort the running kernel code"

	bool "Abort on Sanitizer warnings (smaller kernel but less verbose)"

	depends on !COMPILE_TEST

	help

	  Building kernels with Sanitizer features enabled tends to grow
@@ -26,6 +26,14 @@ config UBSAN_TRAP 
	  the system. For some system builders this is an acceptable

	  trade-off.



	  Also note that selecting Y will cause your kernel to Oops

	  with an "illegal instruction" error with no further details

	  when a UBSAN violation occurs. (Except on arm64, which will

	  report which Sanitizer failed.) This may make it hard to

	  determine whether an Oops was caused by UBSAN or to figure

	  out the details of a UBSAN violation. It makes the kernel log

	  output less useful for bug reports.



config CC_HAS_UBSAN_BOUNDS_STRICT

	def_bool $(cc-option,-fsanitize=bounds-strict)

	help